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Yang X, Aguado MT, Helm C, Zhang Z, Bleidorn C. New fossil of Gaoloufangchaeta advances the origin of Errantia (Annelida) to the early Cambrian. ROYAL SOCIETY OPEN SCIENCE 2024; 11:231580. [PMID: 38601033 PMCID: PMC11004674 DOI: 10.1098/rsos.231580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 02/27/2024] [Accepted: 02/28/2024] [Indexed: 04/12/2024]
Abstract
Molecular clock estimates suggest the origin of Annelida dates back to the Ediacaran period, which is in discordance with the first appearance of this taxon in the early Cambrian, as evidenced by the fossil records of stem-group and basally branching crown-group annelids. Using new material from the early Cambrian Guanshan biota (Cambrian Series 2, Stage 4), we re-interpret Gaoloufangchaeta bifurcus Zhao, Li & Selden, 2023, as the earliest known errantian annelid. Gaoloufangchaeta has a prominent anterior end bearing three pairs of putatively sensory appendages and a pair of anterior eyes; a muscular eversible pharynx with papillae is identified. The presence of enlarged parapodia with acicula-like structures and long capillary chaetae suggests a pelagic lifestyle for this taxon. Our phylogenetic analyses recover Gaoloufangchaeta within the Phyllodocida (Pleistoannelida, Errantia), extending the origin of Errantia back to the early Cambrian. Our data are in line with the hypothesis that Annelida diverged before the Cambrian and indicate both morphological and ecological diversification of annelids in the early Cambrian.
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Affiliation(s)
- Xiaoyu Yang
- Yunnan Key Laboratory for Palaeobiology, Institute of Palaeontology, Yunnan University, Kunming650500, People's Republic of China
- Animal Evolution and Biodiversity, Georg-August-Universität Göttingen, Göttingen37073, Germany
| | - M. Teresa Aguado
- Animal Evolution and Biodiversity, Georg-August-Universität Göttingen, Göttingen37073, Germany
| | - Conrad Helm
- Animal Evolution and Biodiversity, Georg-August-Universität Göttingen, Göttingen37073, Germany
| | - Zhiqian Zhang
- School of Fine Arts, Yunnan Normal University, Kunming650500, People's Republic of China
| | - Christoph Bleidorn
- Animal Evolution and Biodiversity, Georg-August-Universität Göttingen, Göttingen37073, Germany
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Mendes SLDASD, Rizzo AE, Paiva PCDE. Unravelling the diversity of Scalibregma Rathke, 1843 (Annelida: Polychaeta: Scalibregmatidae) from southeast Brazilian coast. Zootaxa 2023; 5353:441-454. [PMID: 38220671 DOI: 10.11646/zootaxa.5353.5.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Indexed: 01/16/2024]
Abstract
Scalibregmatidae Malmgren, 1867 is a relatively small family of annelids, with only two taxa reported to Brazil. In this work, we expand the scientific knowledge of this group by presenting two new Scalibregma Rathke, 1843 species. The new species S. lanai sp. nov. and S. cinthyae sp. nov. were collected during an expedition to the Campos and Santos oceanographic basins. Scalibregma cinthyae sp. nov. is unique among its congeners by the presence of two rows of paired lobes on the mouths upper and lower lips, whereas S. lanai sp. nov. is unique among its congeners by the presence of two rows of paired lobes on the mouths lower lip, branchiae from chaetigers 35, and lyrate chaetae with equal tynes. We provide an identification key to all Scalibregma species.
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Affiliation(s)
| | - Alexandra E Rizzo
- Universidade do Estado do Rio de Janeiro; Departamento de Zoologia; Laboratrio de Zoologia de Invertebrados.
| | - Paulo Cesar DE Paiva
- Universidade Federal do Rio de Janeiro; Departamento de Zoologia; Laboratrio de Polychaeta.
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3
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Gonzalez BC, González VL, Martínez A, Worsaae K, Osborn KJ. A transcriptome-based phylogeny for Polynoidae (Annelida: Aphroditiformia). Mol Phylogenet Evol 2023:107811. [PMID: 37169231 DOI: 10.1016/j.ympev.2023.107811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 03/31/2023] [Accepted: 05/05/2023] [Indexed: 05/13/2023]
Abstract
Polynoidae is the most diverse radiation of Aphroditiformia and one of the most successful groups of all Annelida in terms of diversity and habitats colonized. With such an unmatched diversity, phylogenetic investigations have struggled to understand their evolutionary relationships. Previous phylogenetic analyses have slowly increased taxon sampling and employed methodologies, but despite their diversity and biological importance, large genomic sampling is limited. To investigate the internal relationships within Polynoidae, we conducted the first phylogenomic analyses of the group based on 12 transcriptomes collected from species inhabiting a broad array of habitats, including shallow and deep waters, as well as hydrothermal vents, anchialine caves and the midwater. Our phylogenomic analyses of Polynoidae recovered congruent tree topologies representing the clades Polynoinae, Macellicephalinae and Lepidonotopodinae. Members of Polynoinae and Macellicephalinae clustered in well supported and independent clades. In contrast, Lepidonotopodinae taxa were always recovered nested within Macellicephalinae. Though our sampling only covers a small proportion of the species known for Polynoidae, our results provide a robust phylogenomic framework to build from, emphasizing previously hypothesized relationships between Macellicephalinae and Lepidonotopodinae taxa, while providing new insights on the origin of enigmatic cave and pelagic lineages.
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Affiliation(s)
- Brett C Gonzalez
- Smithsonian Institution, National Museum of Natural History, Department of Invertebrate Zoology, P.O. Box 37012, Washington D.C., USA.
| | - Vanessa L González
- Global Genome Initiative, National Museum of Natural History, Smithsonian Institution, P.O. Box 37012, Washington, D.C., USA
| | - Alejandro Martínez
- Molecular Ecology Group (MEG), Water Research Institute (IRSA), National Research Council of Italy (CNR), Largo Tonolli, 50, 28922. Pallanza, Italy
| | - Katrine Worsaae
- Marine Biological Section, Department of Biology, University of Copenhagen, Universitetsparken 4, Copenhagen Ø, Denmark
| | - Karen J Osborn
- Smithsonian Institution, National Museum of Natural History, Department of Invertebrate Zoology, P.O. Box 37012, Washington D.C., USA; Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039, USA
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Tilic E, Herkenrath T, Kirfel G, Bartolomaeus T. The cellular 3D printer of a marine bristle worm-chaetogenesis in Platynereis dumerilii (Audouin & Milne Edwards, 1834) (Annelida). Cell Tissue Res 2023; 391:305-322. [PMID: 36562865 PMCID: PMC9889436 DOI: 10.1007/s00441-022-03731-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 12/08/2022] [Indexed: 12/24/2022]
Abstract
Annelid chaetae are extracellular chitinous structures that are formed in an extracellular epidermal invagination, the chaetal follicle. The basalmost cell of this follicle, the chaetoblast, serves like a 3D-printer as it dynamically shapes the chaeta. During chaetogenesis apical microvilli of the chaetoblast form the template for the chaeta, any structural details result from modulating the microvilli pattern. This study describes this process in detail in the model organism Platynereis dumerilii and clarifies some aspects of chaetogenesis in its close relative Nereis vexillosa, the first annelid in which the ultrastructure of chaetogenesis had been described. Nereid species possess compound chaetae characteristic for numerous subgroups of errant annelids. The distal most section of these chaetae is movable; a hinge connects this part of the chaeta to the shaft. Modulation of the microvilli and differences in their structure, diameter and number of microvilli, and their withdrawal and reappearance determine the shape of these compound chaetae. Chaetal structure and pattern also change during life history. While larvae possess a single type of chaeta (in addition to internal aciculae), juveniles and adults possess two types of chaetae that are replaced by large paddle-shaped chaetae in swimming epitokous stages. Chaetogenesis is a continuous process that lasts during the entire lifespan. The detailed developmental sequence of chaetae and their site of formation are very similar within species and species groups. We expect that similarity results from a conserved gene regulatory network making this an optimal system to test the phylogenetic affinity of taxa and the homology of their chaetae.
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Affiliation(s)
- Ekin Tilic
- Institute of Evolutionary Biology and Animal Ecology, Rheinische Friedrich-Wilhelms-Universität Bonn, An der Immenburg 1, Bonn, 53121 Germany ,Marine Biological Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Tim Herkenrath
- Institute of Evolutionary Biology and Animal Ecology, Rheinische Friedrich-Wilhelms-Universität Bonn, An der Immenburg 1, Bonn, 53121 Germany
| | - Gregor Kirfel
- Institute of Cell Biology, Rheinische Friedrich-Wilhelms-Universität Bonn, Ulrich-Haberland-Str. 61a, Bonn, 53121 Germany
| | - Thomas Bartolomaeus
- Institute of Evolutionary Biology and Animal Ecology, Rheinische Friedrich-Wilhelms-Universität Bonn, An der Immenburg 1, Bonn, 53121 Germany
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Ma WR, Chen QX, Bai JL, Hua BZ. Ultrastructure of the dorsal ocellus of Bittacus planus larvae (Mecoptera: Bittacidae) with evolutionary significance. ARTHROPOD STRUCTURE & DEVELOPMENT 2023; 72:101234. [PMID: 36708647 DOI: 10.1016/j.asd.2023.101234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
The Bittacidae are unique in holometabolous insects in that their larvae bear a dorsal ocellus on the frons. The fine structure of the dorsal ocellus, however, has not been investigated to date. Here, the ultrastructure of the larval dorsal ocellus was studied in the hangingfly Bittacus planus Cheng, 1949 using light, scanning, and transmission electron microscopy. The dorsal ocellus of the larvae comprises a cornea, corneagenous cells, and retinula cells. The cornea is a laminated structure. A layer of corneagenous cells is located below the cornea. Numerous retinula cells are arranged tightly beneath the corneagenous cells. The retinula cells modify their adjacent membranes into numerous linear microvilli, which form an analogue of the rhabdom among adjacent retinula cells. The results show that the dorsal ocellus of larval Bittacidae is a highly vestigial organ and appears to be degenerating during the postembryonic development. The presence of the vestigial dorsal ocellus is likely to represent an ancestral plesiomorphy of holometabolous insects, providing new evidence for exploring the evolutionary origin of holometabolous larvae.
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Affiliation(s)
- Wan-Ruo Ma
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Qing-Xiao Chen
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China; College of Horticulture and Plant Protection, Henan University of Science and Technology, Luoyang, Henan, 471023, China
| | - Jia-Li Bai
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Bao-Zhen Hua
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China.
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Assis JEDE, Souza JRBDE, Fitzhugh K, Christoffersen ML. A new species of Euclymene (Maldanidae, Annelida) from Brazil, with new combinations, and phylogenetic implications for Euclymeninae. AN ACAD BRAS CIENC 2022; 94:e20210283. [PMID: 36541974 DOI: 10.1590/0001-3765202220210283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 06/27/2021] [Indexed: 12/23/2022] Open
Abstract
Maldanids are tube-building polychaetes, known as bamboo-worms; inhabit diverse marine regions throughout the world. The subfamily Euclymeninae was proposed to include forms with anal and cephalic plates, a funnel-shaped pygidium, and a terminal anus. Euclymene, the type genus of Euclymeninae, has about 18 valid species. Euclymene vidali sp. nov. is defined and members of the species described from Northeastern Brazil. Members of this species have 23 chaetigers, and one pre-pygidial achaetous segment; nuchal grooves extend through three quarters of the cephalic plate, and there is one acicular spine with a denticulate tip. Euclymene africana, and E. watsoni, are here recognized, respectively, as Isocirrus africana comb. nov., and I. watsoni comb. nov. Three monotypic genera are invalid: Macroclymenella, Eupraxillella, and Pseudoclyemene; their species should be recognized as Clymenella stewartensis com. nov., Praxillella antarctica com. nov., and Praxillela quadrilobata com. nov., respectively. An identification key and a comparative table for all species of Euclymene are provided. A comparative table for all genera of Euclymeninae is also furnished. The paraphyletic status of Euclymene and Euclymeninae is discussed. The taxon Maldanoplaca is not code compliant and should only be regarded as an informal name.
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Affiliation(s)
- José Eriberto DE Assis
- Prefeitura Municipal de Bayeux, Departamento de Educação Básica, Rua Santa Tereza, 600, 58306-070 Bayeux, PB, Brazil
| | - José Roberto Botelho DE Souza
- Universidade Federal de Pernambuco, Centro de Biociências, Departamento de Zoologia, Av. Prof. Morais Rego, 1235, 50670-901 Recife, PE, Brazil
| | - Kirk Fitzhugh
- Natural History Museum of Los Angeles County, 900 Exposition Blvd, 90007 Los Angeles, California, USA
| | - Martin Lindsey Christoffersen
- Universidade Federal da Paraíba, Centro de Ciências Exatas e da Natureza, Departamento de Sistemática e Ecologia, Cidade Universitária, 58059-900 João Pessoa, PB, Brazil
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Barroso M, Moreira J, Parapar J. Long forgotten: Eunice woodwardi Baird, 1869 (Annelida, Eunicidae) revisited, with an insight on internal anatomy. PeerJ 2022; 10:e13126. [PMID: 35441057 PMCID: PMC9013482 DOI: 10.7717/peerj.13126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/25/2022] [Indexed: 01/12/2023] Open
Abstract
Eunice woodwardiBaird, 1869, originally described from the Ría de A Coruña (NW Iberian Peninsula), has been overlooked and never reported from the Atlantic coast of Spain after original description and the subsequent redescription of the holotype. In the present study, we revised comparatively the holotype, newly collected specimens of this species and specimens identified as Eunice vittata (Delle Chiaje, 1829) from western Mediterranean Sea. The validity of E. woodwardi is supported and previous descriptions are complemented after a throughout study of the external morphology by means of light compound microscopy and scanning electron microscopy, and that of the internal anatomy by histological sectioning and micro-computed tomography. The presence of eyes, nuchal organs, dorsal and ventral ciliary organs on parapodial cirri and paired nephridia in most segments is confirmed in E. woodwardi; the digestive tract is clearly regionalized and divided into pharynx, oesophagus, stomach, fore, mid- and hind intestine. The presence of E. woodwardi in the Ría de Ferrol is also reported, and we suggest that previous records of E. vittata in NW Iberian Peninsula should be reviewed. Eunice woodwardi is distinguished by a set of characters such as having non-articulated and non-constricted cephalic appendages, the maxillary formula, the range of branchial distribution, maximum number of branchial filaments, number of limbate and compound falciger chaetae per parapodium, the presence of an apical mucro in the guard of falciger chaetae blades and the number of teeth in pectinate chaetae. Epibiont Ciliophora on branchiae are also reported.
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Affiliation(s)
- María Barroso
- Departamento de Bioloxía, Universidade da Coruña, A Coruña, Spain
| | - Juan Moreira
- Departamento de Biología (Zoología) & Centro de Investigación en Biodiversidad y Cambio Global (CIBC-UAM), Universidad Autónoma de Madrid, Madrid, Spain
| | - Julio Parapar
- Departamento de Bioloxía, Universidade da Coruña, A Coruña, Spain
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9
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de Oliveira AL, Mitchell J, Girguis P, Bright M. Novel insights on obligate symbiont lifestyle and adaptation to chemosynthetic environment as revealed by the giant tubeworm genome. Mol Biol Evol 2021; 39:6454105. [PMID: 34893862 PMCID: PMC8789280 DOI: 10.1093/molbev/msab347] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The mutualism between the giant tubeworm Riftia pachyptila and its endosymbiont Candidatus Endoriftia persephone has been extensively researched over the past 40 years. However, the lack of the host whole genome information has impeded the full comprehension of the genotype/phenotype interface in Riftia. Here we described the high-quality draft genome of Riftia, its complete mitogenome, and tissue-specific transcriptomic data. The Riftia genome presents signs of reductive evolution, with gene family contractions exceeding expansions. Expanded gene families are related to sulphur metabolism, detoxification, anti-oxidative stress, oxygen transport, immune system, and lysosomal digestion, reflecting evolutionary adaptations to the vent environment and endosymbiosis. Despite the derived body plan, the developmental gene repertoire in the gutless tubeworm is extremely conserved with the presence of a near intact and complete Hox cluster. Gene expression analyses establishes that the trophosome is a multi-functional organ marked by intracellular digestion of endosymbionts, storage of excretory products and haematopoietic functions. Overall, the plume and gonad tissues both in contact to the environment harbour highly expressed genes involved with cell cycle, programmed cell death, and immunity indicating a high cell turnover and defence mechanisms against pathogens. We posit that the innate immune system plays a more prominent role into the establishment of the symbiosis during the infection in the larval stage, rather than maintaining the symbiostasis in the trophosome. This genome bridges four decades of physiological research in Riftia, whilst simultaneously provides new insights into the development, whole organism functions and evolution in the giant tubeworm.
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Affiliation(s)
| | - Jessica Mitchell
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Peter Girguis
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Monika Bright
- Department of Functional and Evolutionary Ecology, University of Vienna, Austria
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May the palps be with you – new insights into the evolutionary origin of anterior appendages in Terebelliformia (Annelida). BMC ZOOL 2021; 6:30. [PMID: 37170288 PMCID: PMC10124185 DOI: 10.1186/s40850-021-00094-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 10/19/2021] [Indexed: 01/21/2023] Open
Abstract
Abstract
Background
Head appendages in Annelida contribute significantly to the immense morphological diversity in this spiralian taxon. Nevertheless, the evolutionary origin of annelid antennae, palps, cirri and tentacles are part of vast theories and debates that took place over decades. One of these heavily discussed groups are the Terebelliformia, which bear numerous anterior tentacles originating from different regions of the head. The question, whether these tentacles are homologous to feeding palps in other annelids or if these structures evolved convergently in terebellids and the remaining taxa, has been highly debated in the past.
Results
By using morphological methods including immunohistochemistry, confocal microscopy, Azan-stained serial sections and 3D-visualisation, we are able to shed new light and a fresh look on the old question of the evolutionary origin of the buccal tentacles and their associated head structures in Terebelliformia. Our investigations show that the brains of the ampharetid Hypania invalida and the aulophora larvae of Lanice conchilega (Terebellidae) consist of a dorsal, more prominent and a more slender, ventral brain region. Neurite bundles innervating the buccal tentacles split off from the ventral and dorsal root within the ventral brain region and thus originate from the dorsal and ventral root of the circumoesophageal connectives. Hence, the observed neurite bundles fulfil the morphological criteria for the innervating neurite bundles of feeding palps known from Paleoannelida.
Conclusions
We disagree with former conclusions that buccal tentacles are part of the alimentary canal. Based on the presented data, the buccal tentacles of terebelliform taxa are innervated by neurite bundles and can be homologized with peristomial feeding palps of other Annelida.
Our comparative investigations reveal important insights into morphological changes during the evolution of anterior head appendages in Terebelliformia and Annelida in general. Nevertheless, our analyses also illustrate the gaps in knowledge and that more investigations throughout the annelid tree are necessary to explain and understand the huge diversity of annelid anterior appendages.
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Buhre JS, Purschke G. Ultrastructure and functional morphology of the dorsal organs in Scoloplos armiger (Annelida, Sedentaria, Orbiniida). ZOOMORPHOLOGY 2021. [DOI: 10.1007/s00435-021-00545-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
AbstractAnnelids and particularly polychaetes possess a great variety of sensory organs and respond to numerous sensory stimuli. Although eyes and nuchal organs are comparatively well studied, the so-called dorsal organs are among the lesser-known sense organs in aquatic annelids. Moreover, they are known to be restricted to only two out of approximately 80 families of polychaetes—Orbiniidae and Spionidae—which are not closely related. These organs have been regarded as segmentally repeated nuchal organs in the latter taxon, but in Orbiniidae, data are lacking, although it is known that the organs occur almost along the entire trunk except for the anterior-most segments. Furthermore, although the nuchal organ ultrastructure is known to be comparatively uniform for many polychaete species, a comparative investigation has not been conducted in Orbiniidae. To bridge this data gap, we examined an intertidal population of the widely distributed species Scoloplos armiger. Although not completely identical, nuchal and dorsal organs show a high degree of correspondence in the examined specimens. Moreover, both organs correspond to the general structure of nuchal organs. They comprise ciliated supportive cells and bipolar receptor cells and are innervated directly from the brain. The supportive cells form subcuticular spaces and olfactory chambers apically protected by specialized microvilli that house the sensory processes—cilia and microvilli—of the monociliated receptor cells. Therefore, it can be concluded that nuchal and dorsal organs are also identical in Orbiniidae. However, despite general correspondence with spionids, convergent evolution in the two taxa appears to be the most parsimonious interpretation.
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Mortimer K, Fitzhugh K, dos Brasil AC, Lana P. Who's who in Magelona: phylogenetic hypotheses under Magelonidae Cunningham & Ramage, 1888 (Annelida: Polychaeta). PeerJ 2021; 9:e11993. [PMID: 35070516 PMCID: PMC8759375 DOI: 10.7717/peerj.11993] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 07/27/2021] [Indexed: 11/21/2022] Open
Abstract
Known as shovel head worms, members of Magelonidae comprise a group of polychaetes readily recognised by the uniquely shaped, dorso-ventrally flattened prostomium and paired ventro-laterally inserted papillated palps. The present study is the first published account of inferences of phylogenetic hypotheses within Magelonidae. Members of 72 species of Magelona and two species of Octomagelona were included, with outgroups including members of one species of Chaetopteridae and four of Spionidae. The phylogenetic inferences were performed to causally account for 176 characters distributed among 79 subjects, and produced 2,417,600 cladograms, each with 404 steps. A formal definition of Magelonidae is provided, represented by a composite phylogenetic hypothesis explaining seven synapomorphies: shovel-shaped prostomium, prostomial ridges, absence of nuchal organs, ventral insertion of palps and their papillation, presence of a burrowing organ, and unique body regionation. Octomagelona is synonymised with Magelona due to the latter being paraphyletic relative to the former. The consequence is that Magelonidae is monotypic, such that Magelona cannot be formally defined as associated with any phylogenetic hypotheses. As such, the latter name is an empirically empty placeholder, but because of the binomial name requirement mandated by the International Code of Zoological Nomenclature, the definition is identical to that of Magelonidae. Several key features for future descriptions are suggested: prostomial dimensions, presence/absence of prostomial horns, morphology of anterior lamellae, presence/absence of specialised chaetae, and lateral abdominal pouches. Additionally, great care must be taken to fully describe and illustrate all thoracic chaetigers in descriptions.
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Affiliation(s)
- Kate Mortimer
- Natural Sciences, Amgueddfa Cymru–National Museum Wales, Cardiff, Wales, United Kingdom
| | - Kirk Fitzhugh
- Natural History Museum of Los Angeles County, Los Angeles, CA, United States of America
| | - Ana Claudia dos Brasil
- Departamento de Biologia Animal, Instituto de Ciências Biológicas e da Saúde, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Paulo Lana
- Centro de Estudos do Mar, Universidade Federal do Paraná, Pontal do Sul, Paraná, Brazil
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Affiliation(s)
- Patrick Beckers
- Institute of Evolutionary Biology and Ecology University of Bonn Bonn Germany
| | - Ekin Tilic
- Institute of Evolutionary Biology and Ecology University of Bonn Bonn Germany
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Abstract
Annelida is a ubiquitous, common and diverse group of organisms, found in terrestrial, fresh waters and marine environments. Despite the large efforts put into resolving the evolutionary relationships of these and other Lophotrochozoa, and the delineation of the basal nodes within the group, these are still unanswered. Annelida holds an enormous diversity of forms and biological strategies alongside a large number of species, following Arthropoda, Mollusca, Vertebrata and perhaps Platyhelminthes, among the species most rich in phyla within Metazoa. The number of currently accepted annelid species changes rapidly when taxonomic groups are revised due to synonymies and descriptions of a new species. The group is also experiencing a recent increase in species numbers as a consequence of the use of molecular taxonomy methods, which allows the delineation of the entities within species complexes. This review aims at succinctly reviewing the state-of-the-art of annelid diversity and summarizing the main systematic revisions carried out in the group. Moreover, it should be considered as the introduction to the papers that form this Special Issue on Systematics and Biodiversity of Annelids.
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On the Diversity of Phyllodocida (Annelida: Errantia), with a Focus on Glyceridae, Goniadidae, Nephtyidae, Polynoidae, Sphaerodoridae, Syllidae, and the Holoplanktonic Families. DIVERSITY-BASEL 2021. [DOI: 10.3390/d13030131] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Phyllodocida is a clade of errantiate annelids characterized by having ventral sensory palps, anterior enlarged cirri, axial muscular proboscis, compound chaetae (if present) with a single ligament, and of lacking dorsolateral folds. Members of most families date back to the Carboniferous, although the earliest fossil was dated from the Devonian. Phyllodocida holds 27 well-established and morphologically homogenous clades ranked as families, gathering more than 4600 currently accepted nominal species. Among them, Syllidae and Polynoidae are the most specious polychaete groups. Species of Phyllodocida are mainly found in the marine benthos, although a few inhabit freshwater, terrestrial and planktonic environments, and occur from intertidal to deep waters in all oceans. In this review, we (1) explore the current knowledge on species diversity trends (based on traditional species concept and molecular data), phylogeny, ecology, and geographic distribution for the whole group, (2) try to identify the main knowledge gaps, and (3) focus on selected families: Alciopidae, Goniadidae, Glyceridae, Iospilidae, Lopadorrhynchidae, Polynoidae, Pontodoridae, Nephtyidae, Sphaerodoridae, Syllidae, Tomopteridae, Typhloscolecidae, and Yndolaciidae. The highest species richness is concentrated in European, North American, and Australian continental shelves (reflecting a strong sampling bias). While most data come from shallow coastal and surface environments most world oceans are clearly under-studied. The overall trends indicate that new descriptions are constantly added through time and that less than 10% of the known species have molecular barcode information available.
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Abstract
Sabellida Levinsen, 1883 is a large morphologically uniform group of sedentary annelids commonly known as fanworms. These annelids live in tubes made either of calcareous carbonate or mucus with agglutinated sediment. They share the presence of an anterior crown consisting of radioles and the division of the body into thorax and abdomen marked by a chaetal and fecal groove inversion. This study synthesises the current state of knowledge about the diversity of fanworms in the broad sense (morphological, ecological, species richness), the species occurrences in the different biogeographic regions, highlights latest surveys, provides guidelines for identification of members of each group, and describe novel methodologies for species delimitation. As some members of this group are well-known introduced pests, we address information about these species and their current invasive status. In addition, an overview of the current evolutionary hypothesis and history of the classification of members of Sabellida is presented. The main aim of this review is to highlight the knowledge gaps to stimulate research in those directions.
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He X, Gilmore SR, Sutherland TF, Hajibabaei M, Miller KM, Westfall KM, Pawlowski J, Abbott CL. Biotic signals associated with benthic impacts of salmon farms from eDNA metabarcoding of sediments. Mol Ecol 2021; 30:3158-3174. [PMID: 33481325 DOI: 10.1111/mec.15814] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 12/06/2020] [Accepted: 01/15/2021] [Indexed: 01/04/2023]
Abstract
Environmental DNA (eDNA) metabarcoding can rapidly characterize the composition and diversity of benthic communities, thus it has high potential utility for routine assessments of benthic impacts of marine finfish farming. In this study, 126 sediment grab samples from 42 stations were collected at six salmon farms in British Columbia, Canada. Benthic community changes were assessed by both eDNA metabarcoding of metazoans and macrofaunal polychaete surveys. The latter was done by analysing 11,466 individuals using a combination of morphology-based taxonomy and DNA barcoding. Study objectives were to: (i) compare biotic signals associated with benthic impacts of salmon farming in the two data sources, and (ii) identify potential eDNA indicators to facilitate monitoring in Canada. Alpha diversity parameters were consistently reduced near fish cage edge and negatively correlated with pore-water sulphide concentration, with coefficients ranging from -0.62 to -0.48. Although Polychaeta are a common indicator group, the negative correlation with pore-water sulphide concentration was much stronger for Nematoda OTU richness (correlation coefficient: -0.86) than for Polychaeta (correlation coefficient: -0.38). Presence/absence of Capitella generally agreed well between the two methods despite that they differed in the volume of sediments sampled and the molecular marker used. Multiple approaches were used to identify OTUs related to organic enrichment statuses. We demonstrate that eDNA metabarcoding generates biotic signals that could be leveraged for environmental assessment of benthic impacts of fish farms in multiple ways: both alpha diversity and Nematoda OTU richness could be used to assess the spatial extent of impact, and OTUs related to organic enrichment could be used to develop local biotic indices.
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Affiliation(s)
- Xiaoping He
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, Canada
| | - Scott R Gilmore
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, Canada
| | - Terri F Sutherland
- Pacific Science Enterprise Centre, Fisheries and Oceans Canada, West Vancouver, BC, Canada
| | - Mehrdad Hajibabaei
- Department of Integrative Biology & Centre for Biodiversity Genomics, University of Guelph, Guelph, ON, Canada
| | - Kristina M Miller
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, Canada
| | - Kristen M Westfall
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, Canada
| | - Jan Pawlowski
- Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland.,Institute of Oceanology, Polish Academy of Sciences, Sopot, Poland.,ID-Gene Ecodiagnostics, Geneva, Switzerland
| | - Cathryn L Abbott
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, BC, Canada
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On the Systematics and Biodiversity of the Opheliidae and Scalibregmatidae. DIVERSITY 2021. [DOI: 10.3390/d13020087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this paper we review the systematics, diversity, and ecology of two related annelid families: Opheliidae Malmgren, 1867 and Scalibregmatidae Malmgren, 1867. Opheliids are deposit-feeders and that are mainly found as burrowers in sandy sediments. Morphologically, opheliids are characterized by the smooth cuticle, as well as the presence of a conspicuous ventral groove, reduced parapodia, and a tubular-shaped structure often projecting from the posterior end. Scalibregmatids are also deposit-feeders, but compared to opheliids, they have a characteristic arenicoliform body, a T-shaped anterior end and a glandular, reticulated epidermis. For each family, we summarize the available information about the evolutionary relationships, taxonomic history, geographical distribution, ecological preferences and diversity of life strategies along with the techniques most commonly used for their study. By highlighting the main gaps in knowledge on each of these topics, this review ultimately aims at stimulating further research into members of these two families in the future.
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Peter MJ, Maceren-Pates M, Pates G, Yoshikuni M, Kurita Y. Germ Cell Development in Male Perinereis nuntia and Gamete Spawning Mechanisms in Males and Females. Zoolog Sci 2021; 37:519-528. [PMID: 33269867 DOI: 10.2108/zs200080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 08/17/2020] [Indexed: 11/17/2022]
Abstract
Perinereis nuntia is a fully segmented worm with complete intersegmental septa. A previous study of females revealed that germ cells of this animal originate in the tail end segment, called the pygidium. Germ cells were duplicated in the pygidium, transferred to a newly generated segment, and then settled in the parapodia. Within each segment, the settled germ cells proliferated in the parapodia and then migrated into a body cavity area to begin meiotic development. Currently, there is not much information about differences between male and female germ cell development. Therefore, we conducted monthly in situ hybridization analyses using the germ cell marker Pn-piwi and histological examinations. Germ cells detected by Pn-piwi initially settled in the distal areas of the parapodia on both sides of each segment, then formed a large germ cell cluster in each parapodium, and finally, small germ cell clusters were formed by the separation of the large clusters. The small clusters migrated to the deeper body cavity area during growth by segment addition. Until the female germ cells began vitellogenesis, the sex of germ cells could not be identified by morphological observation. Thus, male and female P. nuntia may have the same mechanism of germ cell provision to all segments. At the time of spawning, sperm were released from nephridiopores at the 2nd through 15th segments from the pygidium, while eggs were released through ruptures in the skin of 2-3 segments between the 10th and 30th segments from the tail.
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Affiliation(s)
- Maria January Peter
- Fishery Research Laboratory, Kyushu University, 4-46-24, Tsuyazaki, Fukutsu 811-3304, Japan
| | - Mercedes Maceren-Pates
- Mindanao State University-Naawan, Pedro Pagalan St. Poblacion, Naawan, 9023 Misamis Oriental, Philippines
| | - Gaudioso Pates
- Fishery Research Laboratory, Kyushu University, 4-46-24, Tsuyazaki, Fukutsu 811-3304, Japan
| | - Michiyasu Yoshikuni
- Fishery Research Laboratory, Kyushu University, 4-46-24, Tsuyazaki, Fukutsu 811-3304, Japan
| | - Yoshihisa Kurita
- Fishery Research Laboratory, Kyushu University, 4-46-24, Tsuyazaki, Fukutsu 811-3304, Japan,
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Abstract
In this study, we analyze the current state of knowledge on extant Eunicida systematics, morphology, feeding, life history, habitat, ecology, distribution patterns, local diversity and exploitation. Eunicida is an order of Errantia annelids characterized by the presence of ventral mandibles and dorsal maxillae in a ventral muscularized pharynx. The origin of Eunicida dates back to the late Cambrian, and the peaks of jaw morphology diversity and number of families are in the Ordovician. Species richness is heterogeneous among the seven recent families, with more than half of the valid species belonging to the Eunicidae + Onuphidae clade, one of the latest clades to diverge. Eunicidans inhabit soft and hard substrates from intertidal to deep waters in all oceans. The few freshwater species are restricted to Histriobdellidae, a family exclusively commensal/parasite of crustaceans. The reproductive biology, development and ecology of most families are poorly known and the information available suggests low dispersal ability. However, all families have records of widely distributed species. Scrutiny of these wide distributions has often revealed the presence of exotic species or more than one species. The exploration of the deep-sea and of new habitats has led to recent descriptions of new species. Furthermore, the revision of type specimens, the examination of new morphological features and the use of molecular data have revealed hidden biodiversity under unjustified synonyms, poor understanding of morphological features and incomplete descriptions. Molecular studies are still very few or nonexistent for the families Histriobdellidae, Hartmaniellidae, Lumbrineridae and Oenonidae. The integration of new methodologies for morphological and molecular study, along with information on biological and ecological traits appears to be the path to improve the knowledge on the diversity of Eunicida.
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Schmidbaur H, Schwaha T, Franzkoch R, Purschke G, Steiner G. Within-family plasticity of nervous system architecture in Syllidae (Annelida, Errantia). Front Zool 2020; 17:20. [PMID: 32582362 PMCID: PMC7310387 DOI: 10.1186/s12983-020-00359-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 04/03/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The ground pattern underlying the nervous system of the last common ancestor in annelids was long thought to be settled, consisting of a dorsal brain, circumoesophageal connectives and a subepithelial, ladder-like ventral nerve cord with segmental ganglia connected by paired connectives. With the advent of immunocytochemical stainings and confocal laser scanning microscopy, it becomes evident that its architecture is extremely diverse, which makes the reconstruction of a ground pattern in annelida challenging. Whereas the nervous systems of many different families has already been described, only very few studies looked at the diversity of nervous systems within such clades to give a closer estimate on how plastic the annelid nervous system really is. So far, little is known on syllid nervous system architecture, one of the largest and most diverse groups of marine annelids. RESULTS The position of the brain, the circumoesophageal connectives, the stomatogastric nervous system, the longitudinal nerves that traverse each segment and the innervation of appendages are relatively uniform within the clade. Both the number of connectives within the ventral nerve cord and the number of segmental nerves, which in earlier studies were used to infer phylogenetic relationships and to reconstruct an annelid ground pattern, are highly diverse and differ between genera or even within a given genus. Differences in the distribution of somata of the brain, the nuchal innervation and its associated cell bodies were found between Syllinae and Exogoninae and may be subfamily-specific. CONCLUSIONS The nervous system morphology of syllids very likely depends on the taxon-specific ecological requirements. Thus, it is not surprising that in a clade, which occupies such diverse niches as the Annelida, we find similar patterns in phylogenetically widely separated species in similar niches and a high degree of modularity within a family. Only standardized protocols and staining methods can lead to comparable results, but so far different approaches have been taken to describe annelid nervous systems, making homologization of certain structures difficult. This study provides the first thorough description of the nervous system in the family Syllidae, allowing more detailed comparisons between annelid families in the future.
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Affiliation(s)
- Hannah Schmidbaur
- Department of Integrative Zoology, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
- Present address: Department of Molecular Evolution and Development, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Thomas Schwaha
- Department of Integrative Zoology, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Rico Franzkoch
- Zoology and Developmental Biology, Department of Biology and Chemistry, University of Osnabrück, Barbarastr. 11, 49069 Osnabrück, Germany
- Present address: Microbiology, Department of Biology and Chemistry, University of Osnabrück, Barbarastr. 11, 49069 Osnabrück, Germany
| | - Günter Purschke
- Zoology and Developmental Biology, Department of Biology and Chemistry, University of Osnabrück, Barbarastr. 11, 49069 Osnabrück, Germany
| | - Gerhard Steiner
- Department of Integrative Zoology, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
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Stiller J, Tilic E, Rousset V, Pleijel F, Rouse GW. Spaghetti to a Tree: A Robust Phylogeny for Terebelliformia (Annelida) Based on Transcriptomes, Molecular and Morphological Data. BIOLOGY 2020; 9:E73. [PMID: 32268525 PMCID: PMC7236012 DOI: 10.3390/biology9040073] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 04/03/2020] [Accepted: 04/03/2020] [Indexed: 12/23/2022]
Abstract
Terebelliformia-"spaghetti worms" and their allies-are speciose and ubiquitous marine annelids but our understanding of how their morphological and ecological diversity evolved is hampered by an uncertain delineation of lineages and their phylogenetic relationships. Here, we analyzed transcriptomes of 20 terebelliforms and an outgroup to build a robust phylogeny of the main lineages grounded on 12,674 orthologous genes. We then supplemented this backbone phylogeny with a denser sampling of 121 species using five genes and 90 morphological characters to elucidate fine-scale relationships. The monophyly of six major taxa was supported: Pectinariidae, Ampharetinae, Alvinellidae, Trichobranchidae, Terebellidae and Melinninae. The latter, traditionally a subfamily of Ampharetidae, was unexpectedly the sister to Terebellidae, and hence becomes Melinnidae, and Ampharetinae becomes Ampharetidae. We found no support for the recently proposed separation of Telothelepodidae, Polycirridae and Thelepodidae from Terebellidae. Telothelepodidae was nested within Thelepodinae and is accordingly made its junior synonym. Terebellidae contained the subfamily-ranked taxa Terebellinae and Thelepodinae. The placement of the simplified Polycirridae within Terebellinae differed from previous hypotheses, warranting the division of Terebellinae into Lanicini, Procleini, Terebellini and Polycirrini. Ampharetidae (excluding Melinnidae) were well-supported as the sister group to Alvinellidae and we recognize three clades: Ampharetinae, Amaginae and Amphicteinae. Our analysis found several paraphyletic genera and undescribed species. Morphological transformations on the phylogeny supported the hypothesis of an ancestor that possessed both branchiae and chaetae, which is at odds with proposals of a "naked" ancestor. Our study demonstrates how a robust backbone phylogeny can be combined with dense taxon coverage and morphological traits to give insights into the evolutionary history and transformation of traits.
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Affiliation(s)
- Josefin Stiller
- Scripps Institution of Oceanography, University of California, San Diego, CA 92037, USA; (E.T.)
- Centre for Biodiversity Genomics, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Ekin Tilic
- Scripps Institution of Oceanography, University of California, San Diego, CA 92037, USA; (E.T.)
- Institute of Evolutionary Biology and Animal Ecology, University of Bonn, 53121 Bonn, Germany
| | - Vincent Rousset
- Scripps Institution of Oceanography, University of California, San Diego, CA 92037, USA; (E.T.)
| | - Fredrik Pleijel
- Tjärnö Marine Laboratory, Department of Marine Sciences, University of Gothenburg, 405 30 Gothenburg, Sweden;
| | - Greg W. Rouse
- Scripps Institution of Oceanography, University of California, San Diego, CA 92037, USA; (E.T.)
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Marescalchi O, Gargiulo G, Falconi R. Evidence of germline precursors in asexually reproducing Aeolosoma hemprichi and Aeolosoma viride (Annelida, Aeolosomatidae). INVERTEBR REPROD DEV 2020. [DOI: 10.1080/07924259.2019.1699610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Ombretta Marescalchi
- Department of Biological, Geological and Environmental Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Giuseppe Gargiulo
- Department of Pharmacy, Biotechnology and Sport Science, Bologna, Italy
| | - Rosanna Falconi
- Department of Biological, Geological and Environmental Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy
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Beckers P, Helm C, Purschke G, Worsaae K, Hutchings P, Bartolomaeus T. The central nervous system of Oweniidae (Annelida) and its implications for the structure of the ancestral annelid brain. Front Zool 2019; 16:6. [PMID: 30911320 PMCID: PMC6417257 DOI: 10.1186/s12983-019-0305-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 02/26/2019] [Indexed: 11/29/2022] Open
Abstract
Background Recent phylogenomic analyses congruently reveal a basal clade which consists of Oweniidae and Mageloniidae as sister group to the remaining Annelida. These results indicate that the last common ancestor of Annelida was a tube-dwelling organism. They also challenge traditional evolutionary hypotheses of different organ systems, among them the nervous system. In textbooks the central nervous system is described as consisting of a ganglionic ventral nervous system and a dorsally located brain with different tracts that connect certain parts of the brain to each other. Only limited information on the fine structure, however, is available for Oweniidae, which constitute the sister group (possibly together with Magelonidae) to all remaining annelids. Results The brain of Oweniidae is ring- shaped and basiepidermal. Ganglia, higher brain centers or complex sensory organs do not exist; instead the central nervous system is medullary. Posterior to the brain the ventral medullary cord arises directly from the ventral region of the brain in Myriowenia sp. while in Owenia fusiformis two medullary cords arise perpendicular to the brain ring, extend caudally and fuse posterior. The central nervous system is composed of a central neuropil and surrounding somata of the neurons. According to ultrastructural and histological data only one type of neuron is present in the central nervous system. Conclusion The central nervous system of Oweniidae is the simplest in terms of enlargement of the dorsal part of the brain and neuron distribution found among Annelida. Our investigation suggests that neither ganglia nor commissures inside the brain neuropil or clusters of polymorphic neurons were present in the annelid stem species. These structures evolved later within Annelida, most likely in the stem lineage of Amphinomidae, Sipuncula and Pleistoannelida. Palps were supposedly present in the last common ancestor of annelids and innervated by two nerves originating in the dorsal part of the brain. A broader comparison with species of each major spiralian clade shows the medullary nervous system to be a common feature and thus possibly representing the ancestral state of the spiralian nervous system. Moreover, ganglia and clusters of polymorphic neurons seemingly evolved independently in the compared taxa of Spiralia and Annelida. Electronic supplementary material The online version of this article (10.1186/s12983-019-0305-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Patrick Beckers
- 1Institute of Evolutionary Biology, University of Bonn, 53121 Bonn, Germany
| | - Conrad Helm
- 2Johann-Friedrich-Blumenbach Institute for Zoology & Anthropology Animal Evolution and Biodiversity, University of Göttingen, 37073 Göttingen, Germany
| | - Günter Purschke
- 3Department of Developmental Biology and Zoology, University of Osnabrück, 49069 Osnabrück, Germany
| | - Katrine Worsaae
- 4Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Pat Hutchings
- 5Australian Museum Research Institute, Australian Museum, Sydney, NSW 2010 Australia.,6Department of Biological Sciences, Macquarie University, North Ryde, 2109 Australia
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Helm C, Beckers P, Bartolomaeus T, Drukewitz SH, Kourtesis I, Weigert A, Purschke G, Worsaae K, Struck TH, Bleidorn C. Convergent evolution of the ladder-like ventral nerve cord in Annelida. Front Zool 2018; 15:36. [PMID: 30275868 PMCID: PMC6161469 DOI: 10.1186/s12983-018-0280-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/04/2018] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND A median, segmented, annelid nerve cord has repeatedly been compared to the arthropod and vertebrate nerve cords and became the most used textbook representation of the annelid nervous system. Recent phylogenomic analyses, however, challenge the hypothesis that a subepidermal rope-ladder-like ventral nerve cord (VNC) composed of a paired serial chain of ganglia and somata-free connectives represents either a plesiomorphic or a typical condition in annelids. RESULTS Using a comparative approach by combining phylogenomic analyses with morphological methods (immunohistochemistry and CLSM, histology and TEM), we compiled a comprehensive dataset to reconstruct the evolution of the annelid VNC. Our phylogenomic analyses generally support previous topologies. However, the so far hard-to-place Apistobranchidae and Psammodrilidae are now incorporated among the basally branching annelids with high support. Based on this topology we reconstruct an intraepidermal VNC as the ancestral state in Annelida. Thus, a subepidermal ladder-like nerve cord clearly represents a derived condition. CONCLUSIONS Based on the presented data, a ladder-like appearance of the ventral nerve cord evolved repeatedly, and independently of the transition from an intraepidermal to a subepidermal cord during annelid evolution. Our investigations thereby propose an alternative set of neuroanatomical characteristics for the last common ancestor of Annelida or perhaps even Spiralia.
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Affiliation(s)
- Conrad Helm
- Animal Evolution and Biodiversity, Georg-August-University Göttingen, 37073 Göttingen, Germany
| | - Patrick Beckers
- Institute of Evolutionary Biology and Ecology, University of Bonn, 53121 Bonn, Germany
| | - Thomas Bartolomaeus
- Institute of Evolutionary Biology and Ecology, University of Bonn, 53121 Bonn, Germany
| | | | - Ioannis Kourtesis
- Animal Evolution and Biodiversity, Georg-August-University Göttingen, 37073 Göttingen, Germany
| | - Anne Weigert
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| | - Günter Purschke
- Department of Developmental Biology and Zoology, University of Osnabrück, 49069 Osnabrück, Germany
| | - Katrine Worsaae
- Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Torsten H. Struck
- Frontiers in Evolutionary Zoology, Natural History Museum, University of Oslo, P.O. Box 1172, Blindern, NO-0318 Oslo, Norway
| | - Christoph Bleidorn
- Animal Evolution and Biodiversity, Georg-August-University Göttingen, 37073 Göttingen, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany
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Ribeiro RP, Bleidorn C, Aguado MT. Regeneration mechanisms in Syllidae (Annelida). REGENERATION (OXFORD, ENGLAND) 2018; 5:26-42. [PMID: 29721325 PMCID: PMC5911452 DOI: 10.1002/reg2.98] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 02/26/2018] [Accepted: 02/27/2018] [Indexed: 12/16/2022]
Abstract
Syllidae is one of the most species-rich groups within Annelida, with a wide variety of reproductive modes and different regenerative processes. Syllids have striking ability to regenerate their body anteriorly and posteriorly, which in many species is redeployed during sexual (schizogamy) and asexual (fission) reproduction. This review summarizes the available data on regeneration in syllids, covering descriptions of regenerative mechanisms in different species as well as regeneration in relation to reproductive modes. Our survey shows that posterior regeneration is widely distributed in syllids, whereas anterior regeneration is limited in most of the species, excepting those reproducing by fission. The latter reproductive mode is well known for a few species belonging to Autolytinae, Eusyllinae, and Syllinae. Patterns of fission areas have been studied in these animals. Deviations of the regular regeneration pattern or aberrant forms such as bifurcated animals or individuals with multiple heads have been reported for several species. Some of these aberrations show a deviation of the bilateral symmetry and antero-posterior axis, which, interestingly, can also be observed in the regular branching body pattern of some species of syllids.
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Affiliation(s)
- Rannyele P. Ribeiro
- Departamento de BiologíaFacultad de CienciasUniversidad Autónoma de MadridCantoblanco28049MadridSpain
| | - Christoph Bleidorn
- Animal Evolution and BiodiversityGeorg‐August‐Universität Göttingen37073 GöttingenGermany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig04103 LeipzigGermany
| | - M. Teresa Aguado
- Departamento de BiologíaFacultad de CienciasUniversidad Autónoma de MadridCantoblanco28049MadridSpain
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Gouveneaux A, Gielen MC, Mallefet J. Behavioural responses of the yellow emitting annelidTomopteris helgolandicato photic stimuli. LUMINESCENCE 2018; 33:511-520. [DOI: 10.1002/bio.3440] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 10/28/2017] [Accepted: 11/10/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Anaïd Gouveneaux
- Marine Biology Laboratory, Earth Life Institute; Université catholique de Louvain; Louvain-la-Neuve Belgium
| | - Marie-Charlotte Gielen
- Marine Biology Laboratory, Earth Life Institute; Université catholique de Louvain; Louvain-la-Neuve Belgium
| | - Jérôme Mallefet
- Marine Biology Laboratory, Earth Life Institute; Université catholique de Louvain; Louvain-la-Neuve Belgium
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Affiliation(s)
- Charlotte Watson
- Department of Natural Sciences, Museum & Art Gallery of the Northern Territory, Darwin, Australia
| | - Sarah Faulwetter
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research, Heraklion, Greece
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Affiliation(s)
- Jenna M. Moore
- Florida Museum of Natural History University of Florida P. O. Box 117800 Gainesville FL 32611 USA
- Department of Invertebrate Zoology National Museum of Natural History Smithsonian Institution Washington DC 20013 USA
- Scripps Institution of Oceanography UCSD La Jolla CA 92093‐0202 USA
| | - Eijiroh Nishi
- Faculty of Education and Human Sciences Yokohama National University Hodogaya Yokohama Kanagawa 240‐8501 Japan
| | - Greg W. Rouse
- Scripps Institution of Oceanography UCSD La Jolla CA 92093‐0202 USA
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Richter S, Helm C, Meunier FA, Hering L, Campbell LI, Drukewitz SH, Undheim EAB, Jenner RA, Schiavo G, Bleidorn C. Comparative analyses of glycerotoxin expression unveil a novel structural organization of the bloodworm venom system. BMC Evol Biol 2017; 17:64. [PMID: 28259138 PMCID: PMC5336659 DOI: 10.1186/s12862-017-0904-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Accepted: 02/06/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND We present the first molecular characterization of glycerotoxin (GLTx), a potent neurotoxin found in the venom of the bloodworm Glycera tridactyla (Glyceridae, Annelida). Within the animal kingdom, GLTx shows a unique mode of action as it can specifically up-regulate the activity of Cav2.2 channels (N-type) in a reversible manner. The lack of sequence information has so far hampered a detailed understanding of its mode of action. RESULTS Our analyses reveal three ~3.8 kb GLTx full-length transcripts, show that GLTx represents a multigene family, and suggest it functions as a dimer. An integrative approach using transcriptomics, quantitative real-time PCR, in situ hybridization, and immunocytochemistry shows that GLTx is highly expressed exclusively in four pharyngeal lobes, a previously unrecognized part of the venom apparatus. CONCLUSIONS Our results overturn a century old textbook view on the glycerid venom system, suggesting that it is anatomically and functionally much more complex than previously thought. The herein presented GLTx sequence information constitutes an important step towards the establishment of GLTx as a versatile tool to understand the mechanism of synaptic function, as well as the mode of action of this novel neurotoxin.
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Affiliation(s)
- Sandy Richter
- Institute of Biology - Molecular Evolution and Systematics of Animals, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, D-04103 Leipzig, Germany
- Department of Life Sciences, Natural History Museum, Cromwell Rd, London, SW7 5BD UK
| | - Conrad Helm
- Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgate 55, N-5008 Bergen, Norway
| | - Frederic A. Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, University of Queensland, St. Lucia, Brisbane, 4072 QLD Australia
| | - Lars Hering
- Institute of Biology - Department of Zoology, University of Kassel, Heinrich-Plett-Straße 40, D-34132 Kassel, Germany
| | - Lahcen I. Campbell
- Department of Life Sciences, Natural History Museum, Cromwell Rd, London, SW7 5BD UK
- The European Bioinformatics Institute (EMBL-EBI) - Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD UK
| | - Stephan H. Drukewitz
- Institute of Biology - Molecular Evolution and Systematics of Animals, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
| | - Eivind A. B. Undheim
- Centre for Advanced Imaging, University of Queensland, St. Lucia, Brisbane, 4072 QLD Australia
| | - Ronald A. Jenner
- Department of Life Sciences, Natural History Museum, Cromwell Rd, London, SW7 5BD UK
| | - Giampietro Schiavo
- Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London, WC1N 3BG UK
| | - Christoph Bleidorn
- Institute of Biology - Molecular Evolution and Systematics of Animals, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, D-04103 Leipzig, Germany
- Museo Nacional de Ciencias Naturales, Spanish National Research Council (CSIC), Calle José Gutierrez Abascal 2, 28006 Madrid, Spain
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Weidhase M, Beckers P, Bleidorn C, Aguado MT. On the role of the proventricle region in reproduction and regeneration in Typosyllis antoni (Annelida: Syllidae). BMC Evol Biol 2016; 16:196. [PMID: 27716025 PMCID: PMC5050598 DOI: 10.1186/s12862-016-0770-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 09/28/2016] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Syllids are a species rich annelid family possessing remarkable regenerative ability, which is not only the response after traumatic injury, but also a key step during the life cycle of several syllid taxa. In these animals the posterior part of the body becomes an epitoke and is later detached as a distinct unit named stolon. Such a sexual reproductive mode is named schizogamy or stolonization. The prostomium and the proventricle, a modified foregut structure, have been proposed to have a control function during this process, though the concrete mechanisms behind it have never been elucidated. RESULTS By using different experimental set-ups, histology and immunohistochemistry combined with subsequent cLSM analyzes, we investigate and document the regeneration and stolonization in specimens of Typosyllis antoni that were amputated at different levels throughout the antero-posterior body axis. The removal of the anterior end including the proventricle implies an incomplete anterior regeneration as well as severe deviations from the usual reproductive pattern, i.e. accelerated stolonization, masculinization and the occurrence of aberrant stolons. The detailed anatomy of aberrant stolons is described. A histological study of the proventricle revealed no signs of glandular or secretory structures. The ventricle and the caeca are composed of glandular tissue but they are not involved in the reproductive and regenerative processes. CONCLUSIONS As in other investigated syllids, the proventricle region has a significant role during stolonization and reproduction processes in Typosyllis antoni. When the proventricle region is absent, anterior and posterior regeneration are considerably deviated from the general patterns. However, proventricle ultrastructure does not show any glandular component, thereby questioning a direct involvement of this organ itself in the control of reproduction and regeneration. Our findings offer a comprehensive starting point for further studies of regeneration and reproductive control in syllids as well as annelids in general.
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Affiliation(s)
- Michael Weidhase
- Molecular Evolution & Animal Systematics, Institute of Biology, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
| | - Patrick Beckers
- Zoology and Evolutionary Biology, Institute of Evolutionary Biology and Ecology, Rheinische Friedrich-Wilhelms-Universität Bonn, An der Immenburg 1, D-53121 Bonn, Germany
| | - Christoph Bleidorn
- Molecular Evolution & Animal Systematics, Institute of Biology, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
- Museo Nacional de Ciencias Naturales, Spanish Research Council (CSIC), José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - M. Teresa Aguado
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
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Wang Y, Li X. A new Maldane species and a new Maldaninae genus and species (Maldanidae, Annelida) from coastal waters of China. Zookeys 2016:1-16. [PMID: 27551194 PMCID: PMC4977998 DOI: 10.3897/zookeys.603.9125] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 06/16/2016] [Indexed: 11/15/2022] Open
Abstract
Paramaldane, new genus, with type species Paramaldaneglandicinctasp. n., and Maldaneaduncasp. n. (Maldanidae, Polychaeta) are described based on material from the coast of south China. The new genus Paramaldane is similar to Maldane Grube, 1860 and Sabaco Kinberg, 1867, but it clearly differs from all genera within the subfamily Maldaninae by a unique combination of characters: the cephalic plate is almost circular with low, entire and smooth cephalic rim, nuchal grooves small and crescentic, lacking a collar on chaetiger 1, short companion notochaetae, a collar-like glandular band on the anterior part of the sixth chaetiger, and a well-developed anal valve. Paramaldaneglandicinctasp. n. is characterised by having a glandular band on the anterior part of the sixth chaetiger, an almost circular cephalic plate, an entire and smooth cephalic rim, and small crescentic nuchal grooves. Maldaneaduncasp. n. is characterised by a low cephalic rim, nuchal grooves with a strongly curved anterior part and isolated from the cephalic rim. Finally, a taxonomic key to genera of Maldaninae and a comparative table to species of Maldane are provided.
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Affiliation(s)
- Yueyun Wang
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266070, China
| | - Xinzheng Li
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266070, China
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Watson C, Ignacio Carvajal J, Sergeeva NG, Pleijel F, Rouse GW. Free-living calamyzin chrysopetalids (Annelida) from methane seeps, anoxic basins, and whale falls. Zool J Linn Soc 2016. [DOI: 10.1111/zoj.12390] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Charlotte Watson
- Museum & Art Gallery of the Northern Territory; PO Box 4646 Darwin NT 0820 Australia
| | | | - Nelly G. Sergeeva
- Institute of Marine Biological Research; Russian Academy of Science; Sevastopol Russian Federation
| | - Fredrik Pleijel
- Department of Biological and Environmental Sciences; University of Gothenburg; Tjärnö SE-452 96 Strömstad Sweden
| | - Greg W. Rouse
- Scripps Institution of Oceanography; USCD La Jolla; CA 92093-0202 USA
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Bonyadi-Naeini A, Rahimian H, Glasby CJ. A new substance to relax polychaete worms (Annelida) prior to morphological study. Zookeys 2016:1-9. [PMID: 27408556 PMCID: PMC4926697 DOI: 10.3897/zookeys.594.8061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 04/29/2016] [Indexed: 11/18/2022] Open
Abstract
A variety of chemical substances have been used to relax and/or immobilize polychaete worms, and other invertebrates, prior to specimen preparation for morphological examination. To solve difficulties encountered during the study of nereidid polychaetes (Annelida: Phyllodocida), an experiment was designed and carried out to investigate a new relaxing agent to immobilize nereidid specimens and stimulate pharynx eversion. The new substance, Dentol® (Khoraman laboratory, Iran), a dental anesthetic and antiseptic medicine containing 10% Carvacrol as the effective ingredient, was used for the first time and compared with other substances that have been used traditionally in polychaete studies. Crosstab analysis showed significant differences between different treatment groups, with Dentol® providing much better results for all considered criteria.
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Affiliation(s)
- Alieh Bonyadi-Naeini
- Dept. of Biology, Faculty of Science, Razi University, Baghe- e- Abrisham 67149 Kermanshah, Iran
| | - Hassan Rahimian
- Faculty of Biology, College of Science, University of Tehran, Tehran, Iran, P.O.Box 14155-6455
| | - Christopher J Glasby
- Museum and Art Gallery of the Northern Territory, P.O. Box 4646, Darwin, Northern Territory 0801, Australia
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Tilic E, Bartolomaeus T. Structure, function and cell dynamics during chaetogenesis of abdominal uncini in Sabellaria alveolata (Sabellariidae, Annelida). ZOOLOGICAL LETTERS 2016; 2:1. [PMID: 26753097 PMCID: PMC4705615 DOI: 10.1186/s40851-016-0037-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 01/03/2016] [Indexed: 06/01/2023]
Abstract
BACKGROUND Dynamic apical microvilli of a single cell, called the chaetoblast, inside an ectodermal invagination form the template of annelid chaetae. Changes in the pattern of microvilli are frozen in time by release of chitin, such that the structure of the definitive chaeta reflects its formation. Cellular interactions during chaetogenesis also influence the structure of the chaeta. Analysing chaetogenesis allows for testing hypotheses on the homology of certain chaetal types. We used this approach to test whether the unusual uncini in Sabellaria alveolata are homologous to apparently similar uncini in other annelid taxa. RESULTS Our study reveals unexpected details of sabellariid uncini, which mechanically reinforce the neuropodia enabling their use as paddles. The final structure of the chaeta is caused by pulses of microvilli formation and dynamic interaction between the chaetoblast and adjoining follicle cells. Cell dynamics during chaetogenesis of the uncini in Sabellaria alveolata exceeds by far that reported in previous studies on the formation of this type of chaetae. CONCLUSION Despite the superficial similarity of uncini in sabellariids and other annelids, differences in structure and details of formation do not support the homology of this type of chaetae. Chaetogenesis of sabellariid uncini involves unexpected microvilli and cell dynamics, and provides evidence that interactions between cells play a larger role in chaetogenesis than previously expected. In addition to their function as anchors, uncini in Sabellaridae stabilize the paddle-shaped notopodia, as each uncinus possesses a long, thin rod that extends deeply into the notopodium. The rods of all uncini in a single row form a bundle inside the notopodium that additionally serves as a muscle attachment site and thus have a similar function to the inner chaeta (acicula) of errant polychaetes (Aciculata).
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Affiliation(s)
- Ekin Tilic
- Institute of Evolutionary Biology and Ecology, Rheinische Friedrich Wilhelms Universität Bonn, An der Immenburg 1, 53121 Bonn, Germany
| | - Thomas Bartolomaeus
- Institute of Evolutionary Biology and Ecology, Rheinische Friedrich Wilhelms Universität Bonn, An der Immenburg 1, 53121 Bonn, Germany
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Richter S, Schwarz F, Hering L, Böggemann M, Bleidorn C. The Utility of Genome Skimming for Phylogenomic Analyses as Demonstrated for Glycerid Relationships (Annelida, Glyceridae). Genome Biol Evol 2015; 7:3443-62. [PMID: 26590213 PMCID: PMC4700955 DOI: 10.1093/gbe/evv224] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Glyceridae (Annelida) are a group of venomous annelids distributed worldwide from intertidal to abyssal depths. To trace the evolutionary history and complexity of glycerid venom cocktails, a solid backbone phylogeny of this group is essential. We therefore aimed to reconstruct the phylogenetic relationships of these annelids using Illumina sequencing technology. We constructed whole-genome shotgun libraries for 19 glycerid specimens and 1 outgroup species (Glycinde armigera). The chosen target genes comprise 13 mitochondrial proteins, 2 ribosomal mitochondrial genes, and 4 nuclear loci (18SrRNA, 28SrRNA, ITS1, and ITS2). Based on partitioned maximum likelihood as well as Bayesian analyses of the resulting supermatrix, we were finally able to resolve a robust glycerid phylogeny and identified three clades comprising the majority of taxa. Furthermore, we detected group II introns inside the cox1 gene of two analyzed glycerid specimens, with two different insertions in one of these species. Moreover, we generated reduced data sets comprising 10 million, 4 million, and 1 million reads from the original data sets to test the influence of the sequencing depth on assembling complete mitochondrial genomes from low coverage genome data. We estimated the coverage of mitochondrial genome sequences in each data set size by mapping the filtered Illumina reads against the respective mitochondrial contigs. By comparing the contig coverage calculated in all data set sizes, we got a hint for the scalability of our genome skimming approach. This allows estimating more precisely the number of reads that are at least necessary to reconstruct complete mitochondrial genomes in Glyceridae and probably non-model organisms in general.
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Affiliation(s)
- Sandy Richter
- Molecular Evolution and Animal Systematics, Institute of Biology, University of Leipzig, Germany
| | - Francine Schwarz
- Molecular Evolution and Animal Systematics, Institute of Biology, University of Leipzig, Germany
| | - Lars Hering
- Animal Evolution & Development, Institute of Biology, University of Leipzig, Germany Department of Zoology, Institute of Biology, University of Kassel, Germany
| | | | - Christoph Bleidorn
- Molecular Evolution and Animal Systematics, Institute of Biology, University of Leipzig, Germany German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
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Sato-Okoshi W, Okoshi K, Fujiwara Y. A new species of Protodrilus (Annelida, Protodrilidae), covering bone surfaces bright red, in whale-fall ecosystems in the northwest Pacific. THE BIOLOGICAL BULLETIN 2015; 229:209-219. [PMID: 26504161 DOI: 10.1086/bblv229n2p209] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
There are unique ecosystems in the ocean that are driven by chemosynthesis. Whale-fall communities are one of these reducing habitats, and many unknowns are left to be resolved to understand their uniqueness. A new species of the genus Protodrilus was discovered on the exposed bones of sperm whale carcasses found in the waters off Cape Nomamisaki in the northwest Pacific. Protodrilus puniceus sp. nov. was the most abundant annelid to be found on the 2.5-y-old carcasses; the exposed bone surfaces appeared bright red due to the coloration of the innumerable worms covering them. Closer inspection revealed that this species was found in the small pores of both the internal and external surfaces of the bones. P. puniceus shows simple morphology; it has paired palps and pygidial lobes, but no eyespots, nuchal organs, statocysts, or ciliary rings dorso-anteriorly-an exceptional finding in this group. A ventral ciliary band was conspicuous, extending over each segment of the animal. The male of the species possessed paired, separated lateral organs on segments 6-11; salivary glands were inconspicuous. From morphological, biological, and ecological characteristics, P. puniceus showed differences from the already known Protodrilus group of shallow interstitial inhabitants. P. puniceus is thought to be a unique deposit feeder, acquiring nutrients by adhering to organic substances from whale carcasses. This is the first description of this group to be found in the organically enriched whale-fall environments of the deep sea below 200 m and from Japanese waters. Information on a nuclear, 18S ribosomal RNA gene sequence is included.
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Affiliation(s)
- Waka Sato-Okoshi
- Laboratory of Biological Oceanography, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan;
| | - Kenji Okoshi
- Department of Environmental Science, Faculty of Science, Toho University, Chiba 274-8510, Japan; and
| | - Yoshihiro Fujiwara
- Institute of Biogeosciences, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka 237-0061, Japan
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Capa M, Aguado MT, Bakken T. Phylogenetic hypothesis of Sphaerodoridae Malmgren, 1867 (Annelida) and its position within Phyllodocida. Cladistics 2015; 32:335-350. [DOI: 10.1111/cla.12134] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/23/2015] [Indexed: 11/29/2022] Open
Affiliation(s)
- María Capa
- Norwegian University of Science and Technology; NTNU University Museum; NO-7491 Trondheim Norway
| | - M. Teresa Aguado
- Departamento de Biología (Zoología); Universidad Autónoma de Madrid; Cantoblanco 28049 Madrid Spain
| | - Torkild Bakken
- Norwegian University of Science and Technology; NTNU University Museum; NO-7491 Trondheim Norway
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Rota E, de Jong Y. Fauna Europaea: Annelida - Terrestrial Oligochaeta (Enchytraeidae and Megadrili), Aphanoneura and Polychaeta. Biodivers Data J 2015; 3:e5737. [PMID: 26379463 PMCID: PMC4568407 DOI: 10.3897/bdj.3.e5737] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Accepted: 09/07/2015] [Indexed: 11/12/2022] Open
Abstract
Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. This paper provides updated information on the taxonomic composition and distribution of the Annelida - terrestrial Oligochaeta (Megadrili and Enchytraeidae), Aphanoneura and Polychaeta, recorded in Europe. Data on 18 families, 11 autochthonous and 7 allochthonous, represented in our continent by a total of 800 species, are reviewed, beginning from their distinctness, phylogenetic status, diversity and global distribution, and following with major recent developments in taxonomic and faunistic research in Europe. A rich list of relevant references is appended. The Fauna Europaea Annelida - terrestrial Oligochaeta data-set, as completed in 2004, will be updated accordingly.
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Affiliation(s)
| | - Yde de Jong
- University of Amsterdam - Faculty of Science, Amsterdam, Netherlands
- Museum für Naturkunde, Berlin, Germany
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Liu J, Ou Q, Han J, Li J, Wu Y, Jiao G, He T. Lower Cambrian polychaete from China sheds light on early annelid evolution. THE SCIENCE OF NATURE - NATURWISSENSCHAFTEN 2015; 102:34. [PMID: 26017277 PMCID: PMC4446521 DOI: 10.1007/s00114-015-1285-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 04/22/2015] [Accepted: 05/18/2015] [Indexed: 11/29/2022]
Abstract
We herein report a fossilized polychaete annelid, Guanshanchaeta felicia gen. et sp. nov., from the Lower Cambrian Guanshan Biota (Cambrian Series 2, stage 4). The new taxon has a generalized polychaete morphology, with biramous parapodia (most of which preserve the evidence of chaetae), an inferred prostomium bearing a pair of appendages, and a bifid pygidium. G. felicia is the first unequivocal annelid reported from the Lower Cambrian of China. It represents one of the oldest annelids among those from other early Paleozoic Lagerstätten including Sirius Passet from Greenland (Vinther et al., Nature 451: 185-188, 2011) and Emu Bay from Kangaroo island (Parry et al., Palaeontology 57: 1091-1103, 2014), and adds to our increasing roll of present-day animal phyla recognized in the early Cambrian Guanshan Biota. This finding expands the panorama of the Cambrian 'explosion' exemplified by the Guanshan Biota, suggesting the presence of many more fossil annelids in the Chengjiang Lagerstätte and the Kaili Biota. In addition, this new taxon increases our knowledge of early polychaete morphology, which suggests that polychaete annelids considerably diversified in the Cambrian.
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Affiliation(s)
- Jianni Liu
- />Early Life Institute, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an, 710069 China
| | - Qiang Ou
- />Early Life Evolution Laboratory, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, 100083 China
| | - Jian Han
- />Early Life Institute, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an, 710069 China
| | - Jinshu Li
- />Early Life Institute, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an, 710069 China
| | - Yichen Wu
- />Early Life Institute, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an, 710069 China
| | - Guoxiang Jiao
- />Early Life Institute, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an, 710069 China
| | - Tongjiang He
- />Early Life Institute, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an, 710069 China
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Topper TP, Strotz LC, Holmer LE, Zhang Z, Tait NN, Caron JB. Competition and mimicry: the curious case of chaetae in brachiopods from the middle Cambrian Burgess Shale. BMC Evol Biol 2015; 15:42. [PMID: 25886965 PMCID: PMC4477600 DOI: 10.1186/s12862-015-0314-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 02/23/2015] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND One of the first phyla to acquire biomineralized skeletal elements in the Cambrian, brachiopods represent a vital component in unraveling the early evolution and relationships of the Lophotrochozoa. Critical to improving our understanding of lophotrochozoans is the origin, evolution and function of unbiomineralized morphological features, in particular features such as chaetae that are shared between brachiopods and other lophotrochozoans but are poorly understood and rarely preserved. Micromitra burgessensis and Paterina zenobia from the middle Cambrian Burgess Shale are among the most remarkable examples of fossilized chaetae-bearing brachiopods. The form, functional morphology, evolutionary and ecological significance of their chaetae are studied herein. RESULTS Like in Recent forms, the moveable but semi-rigid chaetae fringe both the dorsal and ventral mantle margins, but in terms of length, the chaetae of Burgess Shale taxa can exceed twice the maximum length of the shell from which it projects. This is unique amongst Recent and fossil brachiopod taxa and given their size, prominence and energy investment to the organism certainly had an important functional significance. Micromitra burgessensis individuals are preserved on hard skeletal elements, including conspecific shells, Tubulella and frequently on the spicules of the sponge Pirania muricata, providing direct evidence of an ecological association between two species. Morphological analysis and comparisons with fossil and extant brachiopod chaetae point to a number of potential functions, including sensory, defence, feeding, defouling, mimicry and spatial competition. CONCLUSIONS Our study indicates that it is feasible to link chaetae length to the lack of suitable substrate in the Burgess Shale environment and the increased intraspecific competition associated with this. Our results however, also lend support to the elongated chaetae as an example of Batesian mimicry, of the unpalatable sponge Pirania muricata. We also cannot discount brachiopod chaetae acting as a sensory grille, extending the tactile sensitivity of the mantle into the environment, as an early warning system to approaching predators.
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Affiliation(s)
- Timothy P Topper
- Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, SE - 752 36, Uppsala, Sweden.
- Department of Palaeobiology, Swedish Museum of Natural History, P.O. Box 50007, , SE-104 05, Stockholm, Sweden.
| | - Luke C Strotz
- Department of Biological Sciences, Macquarie University, Sydney, NSW, 2109, Australia.
| | - Lars E Holmer
- Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, SE - 752 36, Uppsala, Sweden.
| | - Zhifei Zhang
- Early Life Institute and Department of Geology, State Key Laboratory for Continental Dynamics, Northwest University, Xian, 710069, China.
| | - Noel N Tait
- Department of Biological Sciences, Macquarie University, Sydney, NSW, 2109, Australia.
| | - Jean-Bernard Caron
- Department of Natural History (Palaeobiology Section), Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, M5S2C6, Canada.
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, M5S3B2, Canada.
- Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto, Ontario, M5S3B1, Canada.
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Martínez A, Di Domenico M, Rouse GW, Worsaae K. Phylogeny and systematics of Protodrilidae (Annelida) inferred with total evidence analyses. Cladistics 2014; 31:250-276. [DOI: 10.1111/cla.12089] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2014] [Indexed: 12/16/2022] Open
Affiliation(s)
- Alejandro Martínez
- Marine Biology Section University of Copenhagen Strandpromenaden 5 3000 Helsingør Denmark
| | - Maikon Di Domenico
- Marine Biology Section University of Copenhagen Strandpromenaden 5 3000 Helsingør Denmark
- Biological Institute University of Campinas (UNICAMP) Zoological Museum “Prof. Dr. Adão José Cardoso” Biological Institute University of Campinas (UNICAMP) R Charles Darwin s/n Bloco N P.O. Box 6109 13083‐863 Campinas SP Brazil
| | - Greg W. Rouse
- Scripps Institution of Oceanography UCSD 9500 Gilman Drive La Jolla CA 92093 USA
| | - Katrine Worsaae
- Marine Biology Section University of Copenhagen Strandpromenaden 5 3000 Helsingør Denmark
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Parapar J, Aguirrezabalaga F, Moreira J. First record of Longosomatidae (Annelida: Polychaeta) from Iceland with a worldwide review of diagnostic characters of the family. J NAT HIST 2014. [DOI: 10.1080/00222933.2013.859316] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Weigert A, Helm C, Meyer M, Nickel B, Arendt D, Hausdorf B, Santos SR, Halanych KM, Purschke G, Bleidorn C, Struck TH. Illuminating the Base of the Annelid Tree Using Transcriptomics. Mol Biol Evol 2014; 31:1391-401. [DOI: 10.1093/molbev/msu080] [Citation(s) in RCA: 221] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Law CJ, Dorgan KM, Rouse GW. Relating divergence in polychaete musculature to different burrowing behaviors: A study using opheliidae (Annelida). J Morphol 2014; 275:548-71. [DOI: 10.1002/jmor.20237] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 10/09/2013] [Accepted: 11/17/2013] [Indexed: 11/09/2022]
Affiliation(s)
- Chris J. Law
- Scripps Institution of Oceanography, University of California San Diego; La Jolla California 92093-0202
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California 95062
| | - Kelly M. Dorgan
- Scripps Institution of Oceanography, University of California San Diego; La Jolla California 92093-0202
- Dauphin Island Sea Laboratory; Dauphin Island Alabama 36528
| | - Greg W. Rouse
- Scripps Institution of Oceanography, University of California San Diego; La Jolla California 92093-0202
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Martínez A, Di Domenico M, Worsaae K. Gain of palps within a lineage of ancestrally burrowing annelids (Scalibregmatidae). ACTA ZOOL-STOCKHOLM 2013. [DOI: 10.1111/azo.12039] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Alejandro Martínez
- Marine Biological Section; University of Copenhagen; Strandpromenaden 5 3000 Helsingør Denmark
| | - Maikon Di Domenico
- Biological Institute; Zoological Museum ‘Prof. Dr. Adão José Cardoso’; University of Campinas (UNICAMP); Charles Darwin s/n N. 6109 Campinas São Paulo Brazil
| | - Katrine Worsaae
- Marine Biological Section; University of Copenhagen; Strandpromenaden 5 3000 Helsingør Denmark
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Sendall K, Salazar-Vallejo SI. Revision of sternaspis otto, 1821 (polychaeta, sternaspidae). Zookeys 2013:1-74. [PMID: 23794844 PMCID: PMC3677357 DOI: 10.3897/zookeys.286.4438] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 03/07/2013] [Indexed: 11/30/2022] Open
Abstract
To the memory of William Ronald Sendall
Sternaspid polychaetes are common and often abundant in soft bottoms in the world oceans. Some authors suggest that only one species should be recognized, whereas others regard a few species as widely distributed in many seas and variable depths from the low intertidal to about 4400 m. There are some problems with species delineation and the distinctive ventro-caudal shield has been disregarded or barely used for identifying species. In order to clarify these issues, the ventral shield is evaluated in specimens from the same locality and its diagnostic potential is confirmed. On this basis, a revision of Sternaspis Otto, 1821 (Polychaeta: Sternaspidae) is presented based upon type materials, or material collected from type localities. The sternaspid body, introvert hooks and shield show three distinct patterns, two genera have seven abdominal segments and tapered introvert hooks, and one genus has eight abdominal segments and spatulate introvert hooks. The ventro-caudal shield has three different patterns: stiff with ribs, and sometimes concentric lines, stiff with feebly-defined ribs but no concentric lines, and soft with firmly adhered sediment particles. Sternaspis is restricted to include species with seven abdominal segments, falcate introvert hooks, and stiff shields, often exhibiting radial ribs, concentric lines or both. Sternaspis includes, besides the type species, Sternaspis thalassemoides Otto, 1821 from the Mediterranean Sea, Sternaspis affinis Stimpson, 1864 from the Northeastern Pacific, Sternaspis africana Augener, 1918, stat. n. from Western Africa, Sternaspis andamanensissp. n. from the Andaman Sea, Sternaspis costata von Marenzeller, 1879 from Japan, Sternaspis fossor Stimpson, 1853 from the Northwestern Atlantic, Sternaspis islandica Malmgren, 1867 from Iceland, Sternaspis maior Chamberlin, 1919 from the Gulf of California, Sternaspis princeps Selenka, 1885 from New Zealand, Sternaspis rietschi Caullery, 1944 from abyssal depths around Indonesia, Sternaspis scutata (Ranzani, 1817) from the Mediterranean Sea, Sternaspis spinosa Sluiter, 1882 from Indonesia, and Sternaspis thorsonisp. n. from the Iranian Gulf. Two genera are newly proposed to incorporate the remaining species: Caulleryaspis and Petersenaspis. Caulleryaspisgen. n. is defined by the presence of falcate introvert hooks, seven abdominal segments, and soft shields with sediment particles firmly adhered on them; it includes two species: Caulleryaspis gudmundssonisp. n. from Iceland and Caulleryaspis laevis (Caullery, 1944) comb. n. from Indonesia. Petersenaspisgen. n. is defined by the presence of spatulate introvert hooks, eight abdominal segments, and stiff shields with poorly defined ribs but no concentric line; it includes Petersenaspis capillata (Nonato, 1966) from Brazil and Petersenaspis palpallatocisp. n. from the Philippines. Neotypes are proposed for eight species: Sternaspis thalassemoides, Sternaspis affinis, Sternaspis africana, Sternaspis costata, Sternaspis fossor, Sternaspis maior, Sternaspis scutata and Sternaspis spinosa, to stabilize these species-group names, and a lectotype is designated for Sternaspis laevis which is transferred to Caulleryaspisgen. n. The geographic range of most species appears to be much smaller than previously indicated, and for some species additional material in good condition is needed to clarify their distributions. Keys to genera and to all species are also included.
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Affiliation(s)
- Kelly Sendall
- Royal British Columbia Museum, Natural History Section, Victoria, Canada
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Mitochondrial genomes to the rescue--Diurodrilidae in the myzostomid trap. Mol Phylogenet Evol 2013; 68:312-26. [PMID: 23563272 DOI: 10.1016/j.ympev.2013.03.026] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 03/19/2013] [Accepted: 03/26/2013] [Indexed: 11/20/2022]
Abstract
Diurodrilidae is a taxon of Lophotrochozoa comprising about six, exclusively interstitial species, which are up to 500μm long and dorsoventrally flattened. Traditionally, Diurodrilidae had been regarded as an annelid family. However, recently Diurodrilidae had been excluded from Annelida and been placed in closer relationship to platyzoan taxa based on both morphological and nuclear rRNA data. Since both, Diurodrilidae and platyzoan taxa, exhibit long branches in the molecular analyses, the close relationship might be due to a long branch attraction artifact. The annelid taxon Myzostomida had been trapped in a similar long branch attraction artifact with platyzoan taxa using nuclear rRNA data, but determination of the nearly complete mitochondrial genome of myzostomids revealed their annelid affinity. Therefore, we determined the nearly complete mitochondrial genome of Diurodrilus subterraneus as well as new nuclear rRNA data for D. subterraneus and some platyzoan taxa. All our analyses of nuclear rRNA and mitochondrial sequence and gene order data presented herein clearly place Diurodrilidae within Annelida and with strong nodal support values in some analyses. Therefore, the previously suggested exclusion of Diurodrilidae from Annelida and its close relationship with platyzoan taxa can be attributed to a long branch artifact. Morphological data do not unambiguously support a platyzoan affinity of Diurodrilidae, but instead would also be in line with a progenetic origin of Diurodrilidae within Annelida.
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