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Segura-García I, Olson JB, Gochfeld DJ, Brandt ME, Chaves-Fonnegra A. Severe hurricanes increase recruitment and gene flow in the clonal sponge Aplysina cauliformis. Mol Ecol 2024; 33:e17307. [PMID: 38444224 DOI: 10.1111/mec.17307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 01/24/2024] [Accepted: 01/30/2024] [Indexed: 03/07/2024]
Abstract
Upright branching sponges, such as Aplysina cauliformis, provide critical three-dimensional habitat for other organisms and assist in stabilizing coral reef substrata, but are highly susceptible to breakage during storms. Breakage can increase sponge fragmentation, contributing to population clonality and inbreeding. Conversely, storms could provide opportunities for new genotypes to enter populations via larval recruitment, resulting in greater genetic diversity in locations with frequent storms. The unprecedented occurrence of two Category 5 hurricanes in close succession during 2017 in the U.S. Virgin Islands (USVI) provided a unique opportunity to evaluate whether recolonization of newly available substrata on coral reefs was due to local (e.g. re-growth of remnants, fragmentation, larval recruitment) or remote (e.g. larval transport and immigration) sponge genotypes. We sampled A. cauliformis adults and juveniles from four reefs around St. Thomas and two in St. Croix (USVI). Using a 2bRAD protocol, all samples were genotyped for single-nucleotide polymorphisms (SNPs). Results showed that these major storm events favoured sponge larval recruitment but did not increase the genetic diversity of A. cauliformis populations. Recolonization of substratum post-storms via clonality was lower (15%) than expected and instead was mainly due to sexual reproduction (85%) via local larval recruitment. Storms did enhance gene flow among and within reef sites located south of St. Thomas and north of St. Croix. Therefore, populations of clonal marine species with low pelagic dispersion, such as A. cauliformis, may benefit from increased frequency and magnitude of hurricanes for the maintenance of genetic diversity and to combat inbreeding, enhancing the resilience of Caribbean sponge communities to extreme storm events.
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Affiliation(s)
- Iris Segura-García
- Harbor Branch Oceanographic Institution, Florida Atlantic University, Fort Pierce, Florida, USA
| | - Julie B Olson
- Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, USA
| | - Deborah J Gochfeld
- National Center for Natural Products Research, University of Mississippi, Oxford, Mississippi, USA
| | - Marilyn E Brandt
- Center for Marine and Environmental Studies, University of the Virgin Islands, St. Thomas, Virgin Islands, USA
| | - Andia Chaves-Fonnegra
- Harbor Branch Oceanographic Institution, Florida Atlantic University, Fort Pierce, Florida, USA
- Harriet L. Wilkes Honors College, Florida Atlantic University, Jupiter, Florida, USA
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2
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Fernández-Álvarez FÁ, Sanchez G, Deville D, Taite M, Villanueva R, Allcock AL. Atlantic Oceanic Squids in the "Grey Speciation Zone". Integr Comp Biol 2023; 63:1214-1225. [PMID: 37604791 PMCID: PMC10755182 DOI: 10.1093/icb/icad116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 08/03/2023] [Accepted: 08/13/2023] [Indexed: 08/23/2023] Open
Abstract
Cryptic species complexes represent an important challenge for the adequate characterization of Earth's biodiversity. Oceanic organisms tend to have greater unrecognized cryptic biodiversity since the marine realm was often considered to lack hard barriers to genetic exchange. Here, we tested the effect of several Atlantic and Mediterranean oceanic barriers on 16 morphospecies of oceanic squids of the orders Oegopsida and Bathyteuthida using three mitochondrial and one nuclear molecular marker and five species delimitation methods. Number of species recognized within each morphospecies differed among different markers and analyses, but we found strong evidence of cryptic biodiversity in at least four of the studied species (Chtenopteryx sicula, Chtenopteryx canariensis, Ancistrocheirus lesueurii, and Galiteuthis armata). There were highly geographically structured units within Helicocranchia navossae that could either represent recently diverged species or population structure. Although the species studied here can be considered relatively passive with respect to oceanic currents, cryptic speciation patterns showed few signs of being related to oceanic currents. We hypothesize that the bathymetry of the egg masses and duration of the paralarval stage might influence the geographic distribution of oceanic squids. Because the results of different markers and different species delimitation methods are inconsistent and because molecular data encompassing broad geographic sampling areas for oceanic squids are scarce and finding morphological diagnostic characters for early life stages is difficult, it is challenging to assess the species boundaries for many of these species. Thus, we consider many to be in the "grey speciation zone." As many oceanic squids have cosmopolitan distributions, new studies combining genomic and morphological information from specimens collected worldwide are needed to correctly assess the actual oceanic squid biodiversity.
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Affiliation(s)
| | - Gustavo Sanchez
- Molecular Genetics Unit, Okinawa Institute of Science and Technology, Onna, Okinawa 904-0412, Japan
| | - Diego Deville
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Hiroshima 739-8528, Japan
| | - Morag Taite
- Ryan Institute and School of Natural Sciences, University of Galway, University Road, Galway H91 TK33, Ireland
| | - Roger Villanueva
- Institut de Ciències del Mar (ICM), CSIC, Passeig Marítim de la Barceloneta 37–49, 08003 Barcelona, Spain
| | - A Louise Allcock
- Ryan Institute and School of Natural Sciences, University of Galway, University Road, Galway H91 TK33, Ireland
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Sampieri BR, Vieira PE, Teixeira MAL, Seixas VC, Pagliosa PR, Amaral ACZ, Costa FO. Molecular diversity within the genus Laeonereis (Annelida, Nereididae) along the west Atlantic coast: paving the way for integrative taxonomy. PeerJ 2021; 9:e11364. [PMID: 34123584 PMCID: PMC8164838 DOI: 10.7717/peerj.11364] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 04/07/2021] [Indexed: 11/20/2022] Open
Abstract
The polychaete genus Laeonereis (Annelida, Nereididae) occurs over a broad geographic range and extends nearly across the entire Atlantic coast of America, from the USA to Uruguay. Despite the research efforts to clarify its diversity and systematics, mostly by morphological and ecological evidence, there is still uncertainty, mainly concerning the species Laeonereis culveri, which constitutes an old and notorious case of taxonomic ambiguity. Here, we revised the molecular diversity and distribution of Laeonereis species based on a multi-locus approach, including DNA sequence analyses of partial segments of the cytochrome c oxidase subunit I (COI), 16S rRNA, and 28S rRNA genes. We examined Laeonereis specimens collected from 26 sites along the American Atlantic coast from Massachusetts (USA) to Mar del Plata (Argentina). Although no comprehensive morphological examination was performed between different populations, the COI barcodes revealed seven highly divergent MOTUs, with a mean K2P genetic distance of 16.9% (from 6.8% to 21.9%), which was confirmed through four clustering algorithms. All MOTUs were geographically segregated, except for MOTUs 6 and 7 from southeastern Brazil, which presented partially overlapping ranges between Rio de Janeiro and São Paulo coast. Sequence data obtained from 16S rRNA and 28S rRNA markers supported the same MOTU delimitation and geographic segregation as those of COI, providing further evidence for the existence of seven deeply divergent lineages within the genus. The extent of genetic divergence between MOTUs observed in our study fits comfortably within the range reported for species of polychaetes, including Nereididae, thus providing a strong indication that they might constitute separate species. These results may therefore pave the way for integrative taxonomic studies, aiming to clarify the taxonomic status of the Laeonereis MOTUs herein reported.
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Affiliation(s)
- Bruno R Sampieri
- Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal.,Museu de Zoologia, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil.,Institute of Science and Innovation for Bio-Sustainability (IB-S), Universidade do Minho, Braga, Portugal
| | - Pedro E Vieira
- Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal.,Institute of Science and Innovation for Bio-Sustainability (IB-S), Universidade do Minho, Braga, Portugal
| | - Marcos A L Teixeira
- Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal.,Institute of Science and Innovation for Bio-Sustainability (IB-S), Universidade do Minho, Braga, Portugal
| | - Victor C Seixas
- Programa de Pós-Graduação em Ecologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo R Pagliosa
- Laboratório de Biodiversidade e Conservação Marinha, Universidade Federal de Santa Catarina, Florianopólis, Santa Catarina, Brazil
| | | | - Filipe O Costa
- Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal.,Institute of Science and Innovation for Bio-Sustainability (IB-S), Universidade do Minho, Braga, Portugal
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Hernández-Hernández T, Miller EC, Román-Palacios C, Wiens JJ. Speciation across the Tree of Life. Biol Rev Camb Philos Soc 2021; 96:1205-1242. [PMID: 33768723 DOI: 10.1111/brv.12698] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 02/13/2021] [Accepted: 02/16/2021] [Indexed: 01/04/2023]
Abstract
Much of what we know about speciation comes from detailed studies of well-known model systems. Although there have been several important syntheses on speciation, few (if any) have explicitly compared speciation among major groups across the Tree of Life. Here, we synthesize and compare what is known about key aspects of speciation across taxa, including bacteria, protists, fungi, plants, and major animal groups. We focus on three main questions. Is allopatric speciation predominant across groups? How common is ecological divergence of sister species (a requirement for ecological speciation), and on what niche axes do species diverge in each group? What are the reproductive isolating barriers in each group? Our review suggests the following patterns. (i) Based on our survey and projected species numbers, the most frequent speciation process across the Tree of Life may be co-speciation between endosymbiotic bacteria and their insect hosts. (ii) Allopatric speciation appears to be present in all major groups, and may be the most common mode in both animals and plants, based on non-overlapping ranges of sister species. (iii) Full sympatry of sister species is also widespread, and may be more common in fungi than allopatry. (iv) Full sympatry of sister species is more common in some marine animals than in terrestrial and freshwater ones. (v) Ecological divergence of sister species is widespread in all groups, including ~70% of surveyed species pairs of plants and insects. (vi) Major axes of ecological divergence involve species interactions (e.g. host-switching) and habitat divergence. (vii) Prezygotic isolation appears to be generally more widespread and important than postzygotic isolation. (viii) Rates of diversification (and presumably speciation) are strikingly different across groups, with the fastest rates in plants, and successively slower rates in animals, fungi, and protists, with the slowest rates in prokaryotes. Overall, our study represents an initial step towards understanding general patterns in speciation across all organisms.
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Affiliation(s)
- Tania Hernández-Hernández
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721-0088, U.S.A.,Catedrática CONACYT asignada a LANGEBIO-UGA Cinvestav, Libramiento Norte Carretera León Km 9.6, 36821, Irapuato, Guanajuato, Mexico
| | - Elizabeth C Miller
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721-0088, U.S.A
| | - Cristian Román-Palacios
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721-0088, U.S.A
| | - John J Wiens
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721-0088, U.S.A
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Costa TAS, Sales JBL, Markaida U, Granados-Amores J, Gales SM, Sampaio I, Vallinoto M, Rodrigues-Filho LFS, Ready JS. Revisiting the phylogeny of the genus Lolliguncula Steenstrup 1881 improves understanding of their biogeography and proves the validity of Lolliguncula argus Brakoniecki & Roper, 1985. Mol Phylogenet Evol 2020; 154:106968. [PMID: 33031931 DOI: 10.1016/j.ympev.2020.106968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 09/14/2020] [Accepted: 09/28/2020] [Indexed: 12/01/2022]
Abstract
The biogeography of American loliginid squids has been improved in recent years, but certain key taxa have been missing. Given that the most accurate phylogenies and estimates of divergence times of common ancestors depend heavily on good taxonomic coverage we have reanalyzed the genus Lolliguncula in light of new samples that increase the geographic and taxonomic coverage. New sequences were produced using standard methods to update an existing dataset for COI, 16S and Rhodopsin markers. Data was analyzed using various species delimitation methods, rigorous phylogenetic analyses and estimates of divergence times between clades. Within Lolliguncula we recover five monophyletic lineages that relate to the known species L. argus, L. diomedeae, L. panamensis, L. brevis North Atlantic and L. brevis South Atlantic. Except when using low divergence thresholds in ABGD, species delimitation methods only identify four of these lineages as distinct species, grouping L. argus and L. diomedeae as a single species. However, considering the reciprocal monophyly, recent divergence time estimate and morphological diagnoses we refrain from synonymizing L. argus within L. diomedeae, considering them very recently diverged species. The biogeography of the American loliginids is discussed, wherein basal cladogenesis in both Lolliguncula and Doryteuthis occur between the Atlantic and Pacific about 45 mya, with subsequent speciation around 20 mya associated with seafloor changes during the formation of the Caribbean. The recent speciation between L. argus and L. diomedeae is associated to oceanic environmental changes associated with glaciation, deep sea cooling and tropical upwelling.
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Affiliation(s)
- Tarcisio A S Costa
- Federal University of Pará, Faculty for Biological Sciences, Alameda Leandro Ribeiro, 68600-000 Bragança, PA, Brazil; Federal University of Pará, Aquatic Molecular Biology Laboratory, Center for Advanced Biodiversity Studies (CEABIO), Av. Perimetral da Ciência, km 01, PCT-Guamá, Lot 11, 66075-750 Belém, PA, Brazil
| | - João B L Sales
- Federal University of Pará, Aquatic Molecular Biology Laboratory, Center for Advanced Biodiversity Studies (CEABIO), Av. Perimetral da Ciência, km 01, PCT-Guamá, Lot 11, 66075-750 Belém, PA, Brazil.
| | - Unai Markaida
- Línea de Pesquerías Artesanales, EL Colegio da la Frontera Sur, Lerma, Campeche, Mexico
| | - Jasmin Granados-Amores
- Universidad Autónoma de Nayarit-Escuela Nacional de Ingeniería Pesquera, San Blas, Nayarit, Mexico
| | - Suellen M Gales
- Federal University of Pará, Aquatic Molecular Biology Laboratory, Center for Advanced Biodiversity Studies (CEABIO), Av. Perimetral da Ciência, km 01, PCT-Guamá, Lot 11, 66075-750 Belém, PA, Brazil
| | - Iracilda Sampaio
- Federal University of Pará, Faculty for Biological Sciences, Alameda Leandro Ribeiro, 68600-000 Bragança, PA, Brazil
| | - Marcelo Vallinoto
- Federal University of Pará, Faculty for Biological Sciences, Alameda Leandro Ribeiro, 68600-000 Bragança, PA, Brazil
| | | | - Jonathan S Ready
- Federal University of Pará, Aquatic Molecular Biology Laboratory, Center for Advanced Biodiversity Studies (CEABIO), Av. Perimetral da Ciência, km 01, PCT-Guamá, Lot 11, 66075-750 Belém, PA, Brazil
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6
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The grass squid Pickfordiateuthis pulchella is a paedomorphic loliginid. Mol Phylogenet Evol 2020; 147:106801. [DOI: 10.1016/j.ympev.2020.106801] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 03/03/2020] [Accepted: 03/18/2020] [Indexed: 11/23/2022]
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7
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de Luna Sales JB, Haimovici M, Ready JS, Souza RF, Ferreira Y, de Cassia Silva Pinon J, Costa LFC, Asp NE, Sampaio I, Schneider H. Surveying cephalopod diversity of the Amazon reef system using samples from red snapper stomachs and description of a new genus and species of octopus. Sci Rep 2019; 9:5956. [PMID: 30976082 PMCID: PMC6459862 DOI: 10.1038/s41598-019-42464-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 03/22/2019] [Indexed: 11/30/2022] Open
Abstract
The cephalopod fauna of the southwestern Atlantic is especially poorly-known because sampling is mostly limited to commercial net-fishing operations that are relatively inefficient at obtaining cephalopods associated with complex benthic substrates. Cephalopods have been identified in the diets of many large marine species but, as few hard structures survive digestion in most cases, the identification of ingested specimens to species level is often impossible. Samples can be identified by molecular techniques like barcoding and for cephalopods, mitochondrial 16S and COI genes have proven to be useful diagnostic markers for this purpose. The Amazon River estuary and continental shelf are known to encompass a range of different substrates with recent mapping highlighting the existence of an extensive reef system, a type of habitat known to support cephalopod diversity. The present study identified samples of the cephalopod fauna of this region obtained from the stomachs of red snappers, Lutjanus purpureus, a large, commercially-important fish harvested by fisheries using traps and hook-and-line gear that are capable of sampling habitats inaccessible to nets. A total of 98 samples were identified using molecular tools, revealing the presence of three squid species and eight MOTUs within the Octopodidae, representing five major clades. These include four known genera, Macrotritopus, Octopus, Scaeurgus and Amphioctopus, and one basal group distinct from all known octopodid genera described here as Lepidoctopus joaquini Haimovici and Sales, new genus and species. Molecular analysis of large predatory fish stomach contents was found to be an incredibly effective extended sampling method for biodiversity surveys where direct sampling is very difficult.
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Affiliation(s)
- João Bráullio de Luna Sales
- Universidade Federal do Pará, Campus Universitário do Marajó-Breves, Faculdade de Ciências Naturais (FACIN), ZIP: 68800-000, Breves, PA, Brazil.
- Laboratório de Lepidopterologia e Ictiologia Integrada, Centro de Estudos Avançados da Biodiversidade, ICB-UFPA, ZIP: 66075-110, Belém, PA, Brazil.
| | - Manuel Haimovici
- Universidade Federal do Rio Grande, Laboratório de Recursos Demersais e Cefalópodes, ZIP: 96201-900, Rio Grande, RS, Brazil
| | - Jonathan Stuart Ready
- Laboratório de Lepidopterologia e Ictiologia Integrada, Centro de Estudos Avançados da Biodiversidade, ICB-UFPA, ZIP: 66075-110, Belém, PA, Brazil
| | | | - Yrlene Ferreira
- Laboratório de Filogenômica e Bioinformática, Instituto de Estudos Costeiros, Universidade Federal do Pará, Campus Universitário de Bragança, ZIP: 68600-000, Bragança, PA, Brazil
| | - Jessica de Cassia Silva Pinon
- Universidade Federal do Pará, Instituto de Educação Matemática e Cientifica, Programa de Pós-Graduação em Educação em Ciências Matemáticas, ZIP: 66075-110, Belém, PA, Brazil
| | - Luis Fernando Carvalho Costa
- Laboratório de Genética e Biologia Molecular, Universidade Federal do Maranhão (UFMA), Centro de Ciências Biológicas e da Saúde, Departamento de Biologia, Campus Bacanga, São Luis, MA, Brazil
| | - Nils Edvin Asp
- Laboratório de Geologia Costeira, UFPA-IECOS, Campus de Bragança, ZIP: 68600-000, Bragança, PA, Brazil
| | - Iracilda Sampaio
- Laboratório de Filogenômica e Bioinformática, Instituto de Estudos Costeiros, Universidade Federal do Pará, Campus Universitário de Bragança, ZIP: 68600-000, Bragança, PA, Brazil
| | - Horacio Schneider
- Laboratório de Filogenômica e Bioinformática, Instituto de Estudos Costeiros, Universidade Federal do Pará, Campus Universitário de Bragança, ZIP: 68600-000, Bragança, PA, Brazil
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Martins RS, Juanicó M. Biology, distribution and geographic variation of loliginid squids (Mollusca: Cephalopoda) off southwestern Atlantic. ZOOLOGIA 2018. [DOI: 10.3897/zoologia.35.e23176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The biology and ecology of southwestern Atlantic loliginid squids have been intensively researched in the last few decades, mostly off the Brazilian southern coast. However, information gathered by scientific research cruisers, either past or recent, is limited. Three species of loliginid squids – the warm-tempered Doryteuthissanpaulensis (Brakoniecki, 1984), plus the tropical D.pleii (Blainville, 1823) and Lolligunculabrevis (Blainville, 1823) – were sampled along 16 degrees of latitude on the southwestern Atlantic (22–38°S). The samples were obtained mostly from oceanographic surveys, but also included squids caught by commercial fisheries, and a few specimens from museum collections. Squid response to abiotic variables, morphological variation and circadian behaviour were surveyed in detail. Doryteuthissanpaulensis can be divided into at least six distinguishable geographical groups, which do not form a cline. In contrast, D.pleii can be divided into only two morphological groups that are very similar. Doryteuthis spp. were heterogeneously distributed on the shelf, whereas L.brevis was confined nearshore. Our data extended the southernmost distribution range of D.pleii by at least nine degrees of latitude, owing to specimens obtained at ~38°S (Mar del Plata, Argentina). Small, immature D.sanpaulensis were sampled inside the Patos Lagoon estuary (~32°S). The morphologically similar Doryteuthis spp. apparently avoid direct competition by concentrating at different depths, displaying different thermal preferences, and inverse circadian levels of activity. The information reported herein may be regarded as a “snapshot” of the ecology of sympatric squids in a marine environment that has not been deeply affected by climate change.
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Pardo-Gandarillas MC, Torres FI, Fuchs D, Ibáñez CM. Updated molecular phylogeny of the squid family Ommastrephidae: Insights into the evolution of spawning strategies. Mol Phylogenet Evol 2017; 120:212-217. [PMID: 29248625 DOI: 10.1016/j.ympev.2017.12.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 11/03/2017] [Accepted: 12/11/2017] [Indexed: 11/28/2022]
Abstract
Two types of spawning strategy have been described for ommastrephid squids: coastal and oceanic. It has been suggested that ancestral ommastrephids inhabited coastal waters and expanded their distribution into the open ocean during global changes in ocean circulation in the Oligocene. This hypothesis could explain the different reproductive strategies in oceanic squids, but has never been tested in a phylogenetic context. In the present study, we assess the coastal-to-open-ocean hypothesis through inferring the evolution of reproductive traits (spawning type) of ommastrephid squids using the phylogenetic comparative method to estimate ancestral states and divergence times. This analysis was performed using a robust molecular phylogeny with three mitochondrial genes (COI, CYTB and 16S) and two nuclear genes (RHO and 18S) for nearly all species of ommastrephid squid. Our results support dividing the Ommastrephidae into the three traditional subfamilies, plus the monotypic subfamily Todaropsinae as proposed previously. Divergence times were found to be older than those suggested. Our analyses strongly suggest that early ommastrephid squids spawned in coastal areas, with some species subsequently switching to spawn in oceanic areas, supporting previous non-tested hypotheses. We found evidence of gradual evolution change of spawning type in ommastrephid squids estimated to have occurred since the Cretaceous.
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Affiliation(s)
- M Cecilia Pardo-Gandarillas
- Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago, Chile
| | - Felipe I Torres
- Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago, Chile; Departamento de Ecología y Biodiversidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, República 440, Santiago, Chile
| | - Dirk Fuchs
- Department of Natural History Sciences, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Christian M Ibáñez
- Departamento de Ecología y Biodiversidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, República 440, Santiago, Chile.
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