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Bryja J, Kostin D, Meheretu Y, Šumbera R, Bryjová A, Kasso M, Mikula O, Lavrenchenko LA. Reticulate Pleistocene evolution of Ethiopian rodent genus along remarkable altitudinal gradient. Mol Phylogenet Evol 2018; 118:75-87. [DOI: 10.1016/j.ympev.2017.09.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 08/24/2017] [Accepted: 09/25/2017] [Indexed: 10/18/2022]
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152
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Species diversity in the marine microturbellarian Astrotorhynchus bifidus sensu lato (Platyhelminthes: Rhabdocoela) from the Northeast Pacific Ocean. Mol Phylogenet Evol 2017; 120:259-273. [PMID: 29248627 DOI: 10.1016/j.ympev.2017.12.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/26/2017] [Accepted: 12/10/2017] [Indexed: 12/21/2022]
Abstract
Increasing evidence suggests that many widespread species of meiofauna are in fact regional complexes of (pseudo-)cryptic species. This knowledge has challenged the 'Everything is Everywhere' hypothesis and also partly explains the meiofauna paradox of widespread nominal species with limited dispersal abilities. Here, we investigated species diversity within the marine microturbellarian Astrotorhynchus bifidus sensu lato in the Northeast Pacific Ocean. We used a multiple-evidence approach combining multi-gene (18S, 28S, COI) phylogenetic analyses, several single-gene and multi-gene species delimitation methods, haplotype networks and conventional taxonomy to designate Primary Species Hypotheses (PSHs). This included the development of rhabdocoel-specific COI barcode primers, which also have the potential to aid in species identification and delimitation in other rhabdocoels. Secondary Species Hypotheses (SSHs) corresponding to morphospecies and pseudo-cryptic species were then proposed based on the minimum consensus of different PSHs. Our results showed that (a) there are at least five species in the A. bifidus complex in the Northeast Pacific Ocean, four of which can be diagnosed based on stylet morphology, (b) the A. bifidus complex is a mixture of sympatric and allopatric species with regional and/or subglobal distributions, (c) sympatry occurs on local (sample sites), regional (Northeastern Pacific) and subglobal (Northern Atlantic, Arctic, Northeastern Pacific) scales. Mechanisms for this co-occurrence are still poorly understood, but we hypothesize they could include habitat differentiation (spatial and/or seasonal) and life history characteristics such as sexual selection and dispersal abilities. Our results also suggest the need for improved sampling and exploration of molecular markers to accurately map gene flow and broaden our understanding of species diversity and distribution of microturbellarians in particular and meiofauna in general.
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153
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Sproul JS, Maddison DR. Cryptic species in the mountaintops: species delimitation and taxonomy of the Bembidion breve species group (Coleoptera: Carabidae) aided by genomic architecture of a century-old type specimen. Zool J Linn Soc 2017. [DOI: 10.1093/zoolinnean/zlx076] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- John S Sproul
- Department of Integrative Biology, Oregon State University, Corvallis, OR, USA
| | - David R Maddison
- Department of Integrative Biology, Oregon State University, Corvallis, OR, USA
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154
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Eilertsen MH, Kongsrud JA, Alvestad T, Stiller J, Rouse GW, Rapp HT. Do ampharetids take sedimented steps between vents and seeps? Phylogeny and habitat-use of Ampharetidae (Annelida, Terebelliformia) in chemosynthesis-based ecosystems. BMC Evol Biol 2017; 17:222. [PMID: 29089027 PMCID: PMC5664827 DOI: 10.1186/s12862-017-1065-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 10/15/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND A range of higher animal taxa are shared across various chemosynthesis-based ecosystems (CBEs), which demonstrates the evolutionary link between these habitats, but on a global scale the number of species inhabiting multiple CBEs is low. The factors shaping the distributions and habitat specificity of animals within CBEs are poorly understood, but geographic proximity of habitats, depth and substratum have been suggested as important. Biogeographic studies have indicated that intermediate habitats such as sedimented vents play an important part in the diversification of taxa within CBEs, but this has not been assessed in a phylogenetic framework. Ampharetid annelids are one of the most commonly encountered animal groups in CBEs, making them a good model taxon to study the evolution of habitat use in heterotrophic animals. Here we present a review of the habitat use of ampharetid species in CBEs, and a multi-gene phylogeny of Ampharetidae, with increased taxon sampling compared to previous studies. RESULTS The review of microhabitats showed that many ampharetid species have a wide niche in terms of temperature and substratum. Depth may be limiting some species to a certain habitat, and trophic ecology and/or competition are identified as other potentially relevant factors. The phylogeny revealed that ampharetids have adapted into CBEs at least four times independently, with subsequent diversification, and shifts between ecosystems have happened in each of these clades. Evolutionary transitions are found to occur both from seep to vent and vent to seep, and the results indicate a role of sedimented vents in the transition between bare-rock vents and seeps. CONCLUSION The high number of ampharetid species recently described from CBEs, and the putative new species included in the present phylogeny, indicates that there is considerable diversity still to be discovered. This study provides a molecular framework for future studies to build upon and identifies some ecological and evolutionary hypotheses to be tested as new data is produced.
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Affiliation(s)
- Mari H Eilertsen
- Department of Biology, University of Bergen, Bergen, Norway.
- K.G. Jebsen Centre for Deep-Sea Research, University of Bergen, Bergen, Norway.
| | - Jon A Kongsrud
- Department of Natural History, University Museum of Bergen, Bergen, Norway
| | - Tom Alvestad
- Department of Natural History, University Museum of Bergen, Bergen, Norway
| | - Josefin Stiller
- Scripps Institution of Oceanography, University of California San Diego, California, USA
| | - Greg W Rouse
- Scripps Institution of Oceanography, University of California San Diego, California, USA
| | - Hans T Rapp
- Department of Biology, University of Bergen, Bergen, Norway
- K.G. Jebsen Centre for Deep-Sea Research, University of Bergen, Bergen, Norway
- Uni Research, Uni Environment, Bergen, Norway
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155
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Abstract
Aspergillus section Restricti together with sister section Aspergillus (formerly Eurotium) comprises xerophilic species, that are able to grow on substrates with low water activity and in extreme environments. We adressed the monophyly of both sections within subgenus Aspergillus and applied a multidisciplinary approach for definition of species boundaries in sect. Restricti. The monophyly of sections Aspergillus and Restricti was tested on a set of 102 isolates comprising all currently accepted species and was strongly supported by Maximum likelihood (ML) and Bayesian inferrence (BI) analysis based on β-tubulin (benA), calmodulin (CaM) and RNA polymerase II second largest subunit (RPB2) loci. More than 300 strains belonging to sect. Restricti from various isolation sources and four continents were characterized by DNA sequencing, and 193 isolates were selected for phylogenetic analyses and phenotypic studies. Species delimitation methods based on multispecies coalescent model were employed on DNA sequences from four loci, i.e., ID region of rDNA (ITS + 28S), CaM, benA and RPB2, and supported recognition of 21 species, including 14 new. All these species were also strongly supported in ML and BI analyses. All recognised species can be reliably identified by all four examined genetic loci. Phenotype analysis was performed to support the delimitation of new species and includes colony characteristics on seven cultivation media incubated at several temperatures, growth on an osmotic gradient (six media with NaCl concentration from 0 to 25 %) and analysis of morphology including scanning electron microscopy. The micromorphology of conidial heads, vesicle dimensions, temperature profiles and growth parameters in osmotic gradient were useful criteria for species identification. The vast majority of species in sect. Restricti produce asperglaucide, asperphenamate or both in contrast to species in sect. Aspergillus. Mycophenolic acid was detected for the first time in at least six members of the section. The ascomata of A. halophilicus do not contain auroglaucin, epiheveadride or flavoglaucin which are common in sect. Aspergillus, but shares the echinulins with sect. Aspergillus.
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Key Words
- Aspergillus canadensis Visagie, Yilmaz, F. Sklenar & Seifert
- Aspergillus clavatophorus F. Sklenar, S.W. Peterson & Hubka
- Aspergillus destruens Zalar, F. Sklenar, S.W. Peterson & Hubka
- Aspergillus domesticus F. Sklenar, Houbraken, Zalar & Hubka
- Aspergillus glabripes F. Sklenar, Ž. Jurjević & Hubka
- Aspergillus hordei F. Sklenar, S.W. Peterson & Hubka
- Aspergillus infrequens F. Sklenar, S.W. Peterson & Hubka
- Aspergillus magnivesiculatus F. Sklenar, Zalar, Ž. Jurjević & Hubka
- Aspergillus pachycaulis F. Sklenar, S.W. Peterson, Ž. Jurjević & Hubka
- Aspergillus penicillioides
- Aspergillus pseudogracilis F. Sklenar, Ž. Jurjević & Hubka
- Aspergillus restrictus
- Aspergillus reticulatus F. Sklenar, Ž. Jurjević, S.W. Peterson & Hubka
- Aspergillus salinicola Zalar, F. Sklenar, Visagie & Hubka
- Aspergillus tardicrescens F. Sklenar, Houbraken, Zalar, & Hubka
- Aspergillus villosus F. Sklenar, S.W. Peterson & Hubka
- Eurotium
- food spoilage
- indoor fungi
- linear discriminant analysis
- multigene phylogeny
- multispecies coalescent model
- sick building syndrome
- xerophilic fungi
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156
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Bernardes SC, Pepato AR, von Rintelen T, von Rintelen K, Page TJ, Freitag H, de Bruyn M. The complex evolutionary history and phylogeography of Caridina typus (Crustacea: Decapoda): long-distance dispersal and cryptic allopatric species. Sci Rep 2017; 7:9044. [PMID: 28831142 PMCID: PMC5567278 DOI: 10.1038/s41598-017-08494-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 06/30/2017] [Indexed: 11/09/2022] Open
Abstract
The evolutionary history of the old, diverse freshwater shrimp genus Caridina is still poorly understood, despite its vast distribution – from Africa to Polynesia. Here, we used nuclear and mitochondrial DNA to infer the phylogeographic and evolutionary history of C. typus, which is one of only four species distributed across the entire range of the genus. Despite this species’ potential for high levels of gene flow, questions have been raised regarding its phylogeographic structure and taxonomic status. We identified three distinct lineages that likely diverged in the Miocene. Molecular dating and ancestral range reconstructions are congruent with C. typus’ early dispersal to Africa, possibly mediated by the Miocene Indian Ocean Equatorial Jet, followed by back dispersal to Australasia after the Jet’s closure. Furthermore, several different species delimitation methods indicate each lineage represents a distinct (cryptic) species, contradicting current morphospecies delimitation of a single C. typus taxon. The evolutionary history of C. typus lineages is complex, in which ancient oceanic current systems and (currently unrecognised) speciation events preceded secondary sympatry of these cryptic species.
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Affiliation(s)
- Samuel C Bernardes
- Laboratório de Acarologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, 31270-901, Brazil.
| | - Almir R Pepato
- Laboratório de Acarologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, 31270-901, Brazil
| | - Thomas von Rintelen
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, Berlin, 10115, Germany
| | - Kristina von Rintelen
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, Berlin, 10115, Germany
| | - Timothy J Page
- Australian Rivers Institute, Griffith University, Nathan, Queensland 4111, Australia.,Water Planning Ecology, Queensland Department of Science, Information Technology and Innovation, Dutton Park, Queensland 4102, Australia
| | - Hendrik Freitag
- Department of Biology, School of Science & Engineering, Ateneo de Manila University, Quezon City, 1108, Philippines
| | - Mark de Bruyn
- School of Biological Sciences, Bangor University, Bangor, LL57 2UW, UK. .,School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia.
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157
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Ito Y, Enju C, Li J, Tanaka N. Evolutionary distinctiveness and conservation priority of the endangered Najas ancistrocarpa (Hydrocharitaceae). SYST BIODIVERS 2017. [DOI: 10.1080/14772000.2017.1358219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Yu Ito
- Plant Phylogenetics and Conservation Group, Centre for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, 650223, P. R. China
| | - Chigaya Enju
- College of Agro-biological Resource Sciences, University of Tsukuba, Tsukuba 305-8577, Japan
| | - Jie Li
- Plant Phylogenetics and Conservation Group, Centre for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, 650223, P. R. China
| | - Norio Tanaka
- Tsukuba Botanical Garden, National Museum of Nature and Science, Tsukuba 305-0005, Japan
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158
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Wagner F, Härtl S, Vogt R, Oberprieler C. "Fix Me Another Marguerite!": Species delimitation in a group of intensively hybridizing lineages of ox-eye daisies (Leucanthemum Mill., Compositae-Anthemideae). Mol Ecol 2017; 26:4260-4283. [PMID: 28502098 DOI: 10.1111/mec.14180] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 04/28/2017] [Accepted: 05/05/2017] [Indexed: 01/26/2023]
Abstract
Delineating species boundaries in the framework of the multi-species coalescent (MSC) proves to be a reliable, objective, and reproducible method in an increasing number of studies. However, the underlying model assumes the lack of gene flow after speciation; an assumption which may be frequently violated in plant evolution. This study evaluates the robustness of currently available species delimitation methods implemented in beast (BFD, BFD*, and dissect) in the closely-knit ox-eye daisy group around Leucanthemum ageratifolium Pau. Comprising five taxa being allopatrically distributed between northern Spain and southern Italy this study group shows signs of hybridization with the widespread and codistributed species Leucanthemum vulgare (Vaill.) Lam. to various extent. As expected, our empirical analyses based on both AFLP fingerprinting and sequence data demonstrate that the robustness of species delimitation results is considerably influenced by the intensity of hybridization among species and the number of hybrid individuals included. Therefore, we set up a methodological pipeline with a first step of identification and subsequent removal of individuals showing admixed genetic patterns caused by actual interbreeding using AFLP-fingerprint and morphometric data, followed by application of different Bayesian MSC species delimitation methods based on the remnant individuals using both AFLP-fingerprint and sequence data (four nuclear markers, five concatenated intergenic spacer regions of the plastid genome). The results argue for acknowledgement of Leucanthemum laciniatum, L. legraeanum, and L. ligusticum as independent species, show the close relationship of L. ageratifolium, L. monspeliense, and L. vulgare, and give rise to the description of three nothospecies new to science.
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Affiliation(s)
- Florian Wagner
- Evolutionary and Systematic Botany Group, Institute of Plant Sciences, University of Regensburg, Regensburg, Germany
| | - Sabine Härtl
- Evolutionary and Systematic Botany Group, Institute of Plant Sciences, University of Regensburg, Regensburg, Germany
| | - Robert Vogt
- Botanic Garden & Botanical Museum Berlin-Dahlem, Freie Universität Berlin, Berlin, Germany
| | - Christoph Oberprieler
- Evolutionary and Systematic Botany Group, Institute of Plant Sciences, University of Regensburg, Regensburg, Germany
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159
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Vitecek S, Kučinić M, Previšić A, Živić I, Stojanović K, Keresztes L, Bálint M, Hoppeler F, Waringer J, Graf W, Pauls SU. Integrative taxonomy by molecular species delimitation: multi-locus data corroborate a new species of Balkan Drusinae micro-endemics. BMC Evol Biol 2017; 17:129. [PMID: 28587671 PMCID: PMC5461746 DOI: 10.1186/s12862-017-0972-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/18/2017] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Taxonomy offers precise species identification and delimitation and thus provides basic information for biological research, e.g. through assessment of species richness. The importance of molecular taxonomy, i.e., the identification and delimitation of taxa based on molecular markers, has increased in the past decade. Recently developed exploratory tools now allow estimating species-level diversity in multi-locus molecular datasets. RESULTS Here we use molecular species delimitation tools that either quantify differences in intra- and interspecific variability of loci, or divergence times within and between species, or perform coalescent species tree inference to estimate species-level entities in molecular genetic datasets. We benchmark results from these methods against 14 morphologically readily differentiable species of a well-defined subgroup of the diverse Drusinae subfamily (Trichoptera, Limnephilidae). Using a 3798 bp (6 loci) molecular data set we aim to corroborate a geographically isolated new species by integrating comparative morphological studies and molecular taxonomy. CONCLUSIONS Our results indicate that only multi-locus species delimitation provides taxonomically relevant information. The data further corroborate the new species Drusus zivici sp. nov. We provide differential diagnostic characters and describe the male, female and larva of this new species and discuss diversity patterns of Drusinae in the Balkans. We further discuss potential and significance of molecular species delimitation. Finally we argue that enhancing collaborative integrative taxonomy will accelerate assessment of global diversity and completion of reference libraries for applied fields, e.g., conservation and biomonitoring.
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Affiliation(s)
- Simon Vitecek
- Department of Limnology and Bio-Oceanography, Faculty of Life Sciences, University of Vienna, Vienna, Austria
- Senckenberg Research Institute and Natural History Museum, Frankfurt’ to ‘Frankfurt am Main, Germany
| | - Mladen Kučinić
- Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Ana Previšić
- Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Ivana Živić
- Institute of Zoology, University of Belgrade-Faculty of Biology, Belgrade, Serbia
| | - Katarina Stojanović
- Institute of Zoology, University of Belgrade-Faculty of Biology, Belgrade, Serbia
| | - Lujza Keresztes
- Center for Systems Biology, Biodiversity and Bioresources, Faculty of Biology and Geology, Babeş-Bolyai University, Cluj-Napoca, Romania
| | - Miklós Bálint
- Senckenberg Biodiversity and Climate Research Centre BIK-F, Frankfurt’ to ‘Frankfurt am Main, Germany
| | - Felicitas Hoppeler
- Senckenberg Biodiversity and Climate Research Centre BIK-F, Frankfurt’ to ‘Frankfurt am Main, Germany
| | - Johann Waringer
- Department of Limnology and Bio-Oceanography, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Wolfram Graf
- Institute of Hydrobiology and Aquatic Ecology Management, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Steffen U. Pauls
- Senckenberg Biodiversity and Climate Research Centre BIK-F, Frankfurt’ to ‘Frankfurt am Main, Germany
- Senckenberg Research Institute and Natural History Museum, Frankfurt’ to ‘Frankfurt am Main, Germany
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160
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Willis SC. One species or four? Yes!...and, no. Or, arbitrary assignment of lineages to species obscures the diversification processes of Neotropical fishes. PLoS One 2017; 12:e0172349. [PMID: 28235096 PMCID: PMC5325279 DOI: 10.1371/journal.pone.0172349] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 02/03/2017] [Indexed: 11/18/2022] Open
Abstract
Species are fundamental units in many biological disciplines, but there is continuing disagreement as to what species are, how to define them, and even whether the concept is useful. While some of this debate can be attributed to inadequate data and insufficient statistical frameworks in alpha taxonomy, an equal part results from the ambiguity over what species are expected to represent by the many who use them. Here, mtDNA data, microsatellite data, and sequence data from 17 nuclear loci are used in an integrated and quantitative manner to resolve the presence of evolutionary lineages, their contemporary and historical structure, and their correspondence to species, in a species complex of Amazonian peacock "bass" cichlids (Cichla pinima sensu lato). Results suggest that the historical narrative for these populations is more complex than can be portrayed by recognizing them as one, two, or four species: their history and contemporary dynamics cannot be unambiguously rendered as discrete units (taxa) at any level without both choosing the supremacy of one delimitation criterion and obscuring the very information that provides insight into the diversification process. This calls into question the utility of species as a rank, term, or concept, and suggests that while biologists may have a reasonable grasp of the structure of evolution, our methods of conveying these insights need updating. The lack of correspondence between evolutionary phenomena and discrete species should serve as a null hypothesis, and researchers should focus on quantifying the diversity in nature at whatever hierarchical level it occurs.
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Affiliation(s)
- Stuart C. Willis
- Department of Life Sciences, Texas A&M University-Corpus Christi, Corpus Christi, Texas, United States of America
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161
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Choi SC. Methods for delimiting species via population genetics and phylogenetics using genotype data. Genes Genomics 2016. [DOI: 10.1007/s13258-016-0458-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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162
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Eberle J, Warnock RCM, Ahrens D. Bayesian species delimitation in Pleophylla chafers (Coleoptera) - the importance of prior choice and morphology. BMC Evol Biol 2016; 16:94. [PMID: 27149864 PMCID: PMC4858874 DOI: 10.1186/s12862-016-0659-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/18/2016] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Defining species units can be challenging, especially during the earliest stages of speciation, when phylogenetic inference and delimitation methods may be compromised by incomplete lineage sorting (ILS) or secondary gene flow. Integrative approaches to taxonomy, which combine molecular and morphological evidence, have the potential to be valuable in such cases. In this study we investigated the South African scarab beetle genus Pleophylla using data collected from 110 individuals of eight putative morphospecies. The dataset included four molecular markers (cox1, 16S, rrnL, ITS1) and morphometric data based on male genital morphology. We applied a suite of molecular and morphological approaches to species delimitation, and implemented a novel Bayesian approach in the software iBPP, which enables continuous morphological trait and molecular data to be combined. RESULTS Traditional morphology-based species assignments were supported quantitatively by morphometric analyses of the male genitalia (eigenshape analysis, CVA, LDA). While the ITS1-based delineation was also broadly congruent with the morphospecies, the cox1 data resulted in over-splitting (GMYC modelling, haplotype networks, PTP, ABGD). In the most extreme case morphospecies shared identical haplotypes, which may be attributable to ILS based on statistical tests performed using the software JML. We found the strongest support for putative morphospecies based on phylogenetic evidence using the combined approach implemented in iBPP. However, support for putative species was sensitive to the use of alternative guide trees and alternative combinations of priors on the population size (θ) and rootage (τ 0 ) parameters, especially when the analysis was based on molecular or morphological data alone. CONCLUSIONS We demonstrate that continuous morphological trait data can be extremely valuable in assessing competing hypotheses to species delimitation. In particular, we show that the inclusion of morphological data in an integrative Bayesian framework can improve the resolution of inferred species units. However, we also demonstrate that this approach is extremely sensitive to guide tree and prior parameter choice. These parameters should be chosen with caution - if possible - based on independent empirical evidence, or careful sensitivity analyses should be performed to assess the robustness of results. Young species provide exemplars for investigating the mechanisms of speciation and for assessing the performance of tools used to delimit species on the basis of molecular and/or morphological evidence.
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Affiliation(s)
- Jonas Eberle
- Zoologisches Forschungsmuseum Alexander Koenig Bonn, Centre of Taxonomy and Evolutionary Research, Adenauerallee 160, 53113, Bonn, Germany
| | - Rachel C M Warnock
- Department of Entomology, Natural History Museum, London, SW7 5BD, UK
- Department of Life Sciences, Silwood Park Campus, Imperial College London, Ascot, SL7 5PY, UK
- School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, UK
| | - Dirk Ahrens
- Zoologisches Forschungsmuseum Alexander Koenig Bonn, Centre of Taxonomy and Evolutionary Research, Adenauerallee 160, 53113, Bonn, Germany.
- Department of Entomology, Natural History Museum, London, SW7 5BD, UK.
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