共查询到20条相似文献，搜索用时 15 毫秒
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Paula Raile Riccardi;Emily Hartop; 《Zoologica scripta》2024,53(5):614-631
The study of biodiversity is fundamental to preserving life on Earth but a challenging endeavour due to the taxonomic neglect associated with hyperdiverse lineages. To overcome this problem, we have implemented for the first time a Large-scale integrative taxonomic (LIT) approach on the hyperdiverse insect family Chloropidae. This lineage of flies is a great fit for implementing emerging protocols such as LIT due to their ecological relevance, abundance and global distribution, poorly known genetic diversity and challenging taxonomy. In this study, we test cost-effective barcoding workflows on nonoptimally preserved chloropid flies from Sweden and then apply targeted morphological validation to accelerate the species recognition process. Our dataset yielded DNA barcodes of 63 species that represent almost one-third of the species diversity from Sweden and 15% of the European diversity. Applying LIT allowed us to uncover two new species and address for the first time three troublesome species complexes through a comprehensive framework. We also provide previously unknown DNA barcodes for 35% of the described species found and address distribution patterns with a focus on grassland environments. We have thus contributed significantly to overcoming the taxonomic neglect of this hyperdiverse lineage by tackling the diversity of chloropids using complementary sources of data, scalable techniques and quickly translating multiple sources of evidence into named species. 相似文献
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The chiefly Holarctic Hydrobius species complex (Coleoptera, Hydrophilidae) currently consists of Hydrobius
arcticus Kuwert, 1890, and three morphological variants of Hydrobius
fuscipes (Linnaeus, 1758): var. fuscipes, var. rottenbergii and var. subrotundus in northern Europe. Here molecular and morphological data are used to test the species boundaries in this species complex. Three gene segments (COI, H3 and ITS2) were sequenced and analyzed with Bayesian methods to infer phylogenetic relationships. The Generalized Mixed Yule Coalescent (GMYC) model and two versions of the Bayesian species delimitation method BPP, with or without an a priori defined guide tree (v2.2 & v3.0), were used to evaluate species limits. External and male genital characters of primarily Fennoscandian specimens were measured and statistically analyzed to test for significant differences in quantitative morphological characters. The four morphotypes formed separate genetic clusters on gene trees and were delimited as separate species by GMYC and by both versions of BPP, despite specimens of Hydrobius
fuscipes
var.
fuscipes and Hydrobius
fuscipes
var.
subrotundus being sympatric. Hydrobius
arcticus and Hydrobius
fuscipes
var.
rottenbergii could only be separated genetically with ITS2, and were delimited statistically with GMYC on ITS2 and with BPP on the combined data. In addition, six or seven potentially cryptic species of the Hydrobius
fuscipes complex from regions outside northern Europe were delimited genetically. Although some overlap was found, the mean values of six male genital characters were significantly different between the morphotypes (p < 0.001). Morphological characters previously presumed to be diagnostic were less reliable to separate Hydrobius
fuscipes
var.
fuscipes from Hydrobius
fuscipes
var.
subrotundus, but characters in the literature for Hydrobius
arcticus and Hydrobius
fuscipes
var.
rottenbergii were diagnostic. Overall, morphological and molecular evidence strongly suggest that Hydrobius
arcticus and the three morphological variants of Hydrobius
fuscipes are separate species and Hydrobius
rottenbergii Gerhardt, 1872, stat. n. and Hydrobius
subrotundus Stephens, 1829, stat. n. are elevated to valid species. An identification key to northern European species of Hydrobius is provided. 相似文献
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Juan F. Díaz‐Nieto Sharon A. Jansa Robert S. Voss 《Zoological Journal of the Linnean Society》2016,176(4):914-940
To assess species‐level diversity in the didelphid marsupial genus Marmosops, we obtained sequence data from the mitochondrial cytochrome b (CYTB) gene from > 200 specimens, including exemplars of every currently recognized species together with multiple specimens of all geographically widespread forms. Analyses of these data using the general mixed Yule coalescent (GMYC) model suggest that the genus could be twice as speciose as currently recognized, but putative species identified by the GMYC criterion require careful evaluation using other data. To assess phylogenetic relationships within Marmosops, we additionally sequenced a large fragment of the breast cancer activating 1 (BRCA1) gene from one specimen each of the putative species identified by the GMYC analyses of CYTB. Maximum likelihood and Bayesian analyses of a concatenated gene (CYTB + BRCA1) matrix revealed a basal dichotomy between two ancient, morphologically diagnosable clades with apparently distinct distributions and adaptive phenotypes. We describe those clades as subgenera and assign 12 nominal taxa to Sciophanes subgen. nov. (with type species Marmosops parvidens) and 27 nominal taxa to the nominotypical subgenus (with type species Marmosops incanus). 相似文献
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Fábio Pinheiro Marcos Vinicius Dantas-Queiroz Clarisse Palma-Silva 《Critical Reviews in Plant Sciences》2018,37(1):54-80
Identifying discontinuous entities within species complexes is a major topic in systematic and evolutionary biology. Comprehensive inventories describing and identifying species rapidly and correctly before they or their habitats disappear is especially important in megadiverse regions, such as South America continent, where a large part of the biodiversity is still unknown and remains to be discovered. Species complexes may account for a substantial number of plant groups in the South American flora, and studies investigating species boundaries in such challenging groups are needed. In this context, multidisciplinary approaches are crucial to understanding the species integrity and boundaries within species complexes. Morphometrics, cytogenetics, anatomy, crossing experiments, and molecular markers have been combined in different ways to investigate species complexes and have helped depict the mechanisms underlying the origin of South American species. Here, we review the current knowledge about plant species complexes on the hyperdiverse South American continent based on a detailed examination of the relevant literature. We discuss the main findings in light of the potential evolutionary mechanisms involved in speciation and suggest future directions in terms of integrating multispecies coalescence methods with several complementary types of morphological, ecological, and geographical data in this research field. 相似文献
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Approaches that integrate multiple independent, yet complimentary, lines of evidence have been effectively utilized to identify and evaluate species diversity. Integrative approaches are especially useful in taxa that exhibit cryptic diversity and are highly morphologically conserved, as well as organisms whose distributions may be sympatric or parapatric. The Incilius coccifer complex in Honduras is comprised of three putative taxa: I. coccifer, I. ibarrai and I. porteri. The taxonomy of the I. coccifer complex has been a source of debate among specialists, with some recognizing three species, while others choose to recognize one widespread taxon. To assess species boundaries and evaluate the taxonomic structure for the I. coccifer complex, we utilized a combination of comprehensive field sampling, molecular phylogenetics and macroecological modelling. Using 58 samples representing all three putative taxa, we generated sequence data from the mitochondrial loci 16S and COI in order to assess genetic diversity and phylogenetic relationships, and tested putative species boundaries using General Mixed Yule‐Coalescent models. To evaluate macroecological differences in the distribution of putative taxa, we utilized maximum entropy modelling and identified areas of suitable and non‐suitable habitat, as well as identifying potential areas of overlap between species habitats. We recovered three clades that broadly correspond to the three named taxa that, while being monophyletic, are separated by relatively small genetic distances. Species distribution models revealed that I. coccifer is macroecologically different than the other two taxa, but that I. ibarrai and I. porteri are highly similar. We uncovered cases of sympatry between pairs of species in at least three localities in Honduras, suggesting the potential for hybridization in these closely related lineages. 相似文献
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Accurate species delimitation is the key to precise estimation of species diversity and is fundamental to most branches of biology. Unclear species boundaries within species complexes could lead to the underestimation of species diversity. However, species delimitation of species complexes remains challenging due to the continuum of phenotypic variations. To robustly examine species boundaries within a species complex, integrative approaches in phylogeny, ecology, and morphology were applied to the Stewartia sinensis complex (Theaceae) endemic to China. Multispecies coalescent-based species delimitation using 572 nuclear ortholog sequences (anchored enrichment) supported reciprocal phylogenetic monophyly of the northern lineage (NL) and southern lineage (SL), which were not sister clades. Niche equivalency and similarity tests demonstrated significant climatic niche differentiation between NL and SL with observed Warren et al.'s I = 0.0073 and Schoener's D = 0.0021. Species distribution modeling also separated their potential distribution. Morphometric analyses suggested significant interlineage differentiation of multiple traits including the ratio of length and width, leaf width, and pedicel length, although overall similarity did not differ. Based on the integrative species concept, two distinct species were proposed with legitimate names of Stewartia gemmata for SL and S. sinensis for NL. Our empirical study of the S. sinensis complex highlights the importance of applying multiple species criteria, in particular the underappreciated niche differentiation, to species delimitation in species complexes pervasive in plants. 相似文献
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Wei Zhang Kimberley D. Lemmen Libin Zhou Spiros Papakostas Steven A. J. Declerck 《Freshwater Biology》2019,64(11):1994-2005
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César Aguilar Perry L. Wood Jr Juan C. Cusi Alfredo Guzmán Frank Huari Mikael Lundberg Emma Mortensen César Ramírez Daniel Robles Juana Suárez Andres Ticona Víctor J. Vargas Pablo J. Venegas Jack W. Sites Jr 《ZooKeys》2013,(364):47-91
Species delimitation studies based on integrative taxonomic approaches have received considerable attention in the last few years, and have provided the strongest hypotheses of species boundaries. We used three lines of evidence (molecular, morphological, and niche envelopes) to test for species boundaries in Peruvian populations of the Liolaemus walkeri complex. Our results show that different lines of evidence and analyses are congruent in different combinations, for unambiguous delimitation of three lineages that were “hidden” within known species, and now deserve species status. Our phylogenetic analysis shows that L. walkeri, L. tacnae and the three new species are strongly separated from other species assigned to the alticolor-bibronii group. Few conventional morphological characters distinguish the new species from closely related taxa and this highlights the need to integrate other sources of data to erect strong hypothesis of species limits. A taxonomic key for known Peruvian species of the subgenus Lioalemus is provided. 相似文献
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Abstract The genus Eois comprises an important part of megadiverse assemblages of geometrid moths in mountain rainforests of southern Ecuador. In this study we report: (i) on the construction of a DNA barcode library of Eois for identification purposes; and (ii) the exploration of species diversity through species delimitation by pair‐wise distance thresholds. COI barcode sequences were generated from 408 individuals (at least 105 species) collected on a narrow geographic scale (～40 km2) in the Reserva Biológica San Francisco. Analyses of barcode sequence divergence showed that species delimitations based solely on external morphology result in broad overlap of intra‐ and interspecific distances. Species delimitation at a 2% pair‐wise distance threshold reveals a clear barcoding gap. Fifty‐two previously unrecognized species were identified, 31 of which could only be distinguished by an integrative taxonomy approach. Twelve additional putative species could only be recognized by threshold‐based delimitation. Most splits resulted in two or three newly perceived cryptic taxa. The present study increased the number of Eois species recorded from that small area of Andean mountain forest from 102 to 154 (morphology‐ plus integrative taxonomy‐based) or even 166 (sequence‐based), leaving the species accumulation curve still far from reaching an asymptote. Notably, in no case did two or more previously distinguished morphospecies have to be lumped. This barcode inventory can be used to match larvae to known adult samples without rearing, and will therefore be of vital help to extend the currently limited knowledge about food plant relationships and host specialization. 相似文献
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Lacie G. Newton James Starrett Brent E. Hendrixson Shahan Derkarabetian Jason E. Bond 《Molecular ecology》2020,29(12):2269-2287
Although species delimitation can be highly contentious, the development of reliable methods to accurately ascertain species boundaries is an imperative step in cataloguing and describing Earth's quickly disappearing biodiversity. Spider species delimitation remains largely based on morphological characters; however, many mygalomorph spider populations are morphologically indistinguishable from each other yet have considerable molecular divergence. The focus of our study, the Antrodiaetus unicolor species complex containing two sympatric species, exhibits this pattern of relative morphological stasis with considerable genetic divergence across its distribution. A past study using two molecular markers, COI and 28S, revealed that A. unicolor is paraphyletic with respect to A. microunicolor. To better investigate species boundaries in the complex, we implement the cohesion species concept and use multiple lines of evidence for testing genetic exchangeability and ecological interchangeability. Our integrative approach includes extensively sampling homologous loci across the genome using a RADseq approach (3RAD), assessing population structure across their geographic range using multiple genetic clustering analyses that include structure , principal components analysis and a recently developed unsupervised machine learning approach (Variational Autoencoder). We evaluate ecological similarity by using large‐scale ecological data for niche‐based distribution modelling. Based on our analyses, we conclude that this complex has at least one additional species as well as confirm species delimitations based on previous less comprehensive approaches. Our study demonstrates the efficacy of genomic‐scale data for recognizing cryptic species, suggesting that species delimitation with one data type, whether one mitochondrial gene or morphology, may underestimate true species diversity in morphologically homogenous taxa with low vagility. 相似文献
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Priscila Barreto de Jesus 《欧洲藻类学杂志》2019,54(2):135-153
The simple and convergent morphologies of many red algae make these species difficult to identify using traditional morphological characters. Many cryptic species have been described in recent years based on molecular datasets, and this has led to the application of an integrative taxonomy approach in species delimitation. Here, we performed several species delimitation methods (mBGD, ABGD, SPN, PTP, GMYCs and GMYCm) based on two different loci (COI-5P and rbcL) in species of the Hypnea cornuta complex. These methods were combined with morphological and phylogenetic data, extensive sampling, analysis of topotype material, and historically relevant herbarium samples. Our findings demonstrate that the groups morphologically assigned to H. cornuta and H. stellulifera consist of five different cryptic species. H. cornuta is a polyphyletic taxon composed of three well-separated lineages, thus requiring sequencing of type or topotype specimens to determine which one is Hypnea cornuta sensu stricto. We have revealed that the distribution of H. stellulifera is limited to Asia, while the Brazilian specimens initially assigned to this species were clarified as a new endemic species: Hypnea cryptica sp. nov. Our results indicated that only an integrative approach combining several lines of evidence, including morphology, nomenclature history, molecular data, biogeography and ecology can correctly solve the taxonomic status of widely distributed cryptic species. 相似文献
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Joshua Tyler Matthew T. Bonfitto Gemma V. Clucas Sushma Reddy Jane L. Younger 《Ecology and evolution》2020,10(24):13836
Gentoo penguins (Pygoscelis papua) are found across the Southern Ocean with a circumpolar distribution and notable genetic and morphological variation across their geographic range. Whether this geographic variation represents species‐level diversity has yet to be investigated in an integrative taxonomic framework. Here, we show that four distinct populations of gentoo penguins (Iles Kerguelen, Falkland Islands, South Georgia, and South Shetlands/Western Antarctic Peninsula) are genetically and morphologically distinct from one another. We present here a revised taxonomic treatment including formal nomenclatural changes. We suggest the designation of four species of gentoo penguin: P. papua in the Falkland Islands, P. ellsworthi in the South Shetland Islands/Western Antarctic Peninsula, P. taeniata in Iles Kerguelen, and a new gentoo species P. poncetii, described herein, in South Georgia. These findings of cryptic diversity add to many other such findings across the avian tree of life in recent years. Our results further highlight the importance of reassessing species boundaries as methodological advances are made, particularly for taxa of conservation concern. We recommend reassessment by the IUCN of each species, particularly P. taeniata and P. poncetii, which both show evidence of decline. 相似文献
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Correct species identification is the basis of ecological studies. Nevertheless, morphological examination alone may not be enough to tell species apart. Here, our integrated molecular and morphological studies demonstrate that the relatively widespread and common neotropical parasitoid wasp Pimpla croceipes Cresson, 1874 (Hymenoptera: Ichneumonidae: Pimplinae) actually consists of two distinct species. The name Pimpla molesta (Smith, 1879), stat. rev. is available for the second species. The two species were identified by DNA barcoding and minor differences in morphology and colouration. Our results support the previous notions that DNA barcoding can complement morphological identification and aid the discovery of cryptic species complexes. 相似文献
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Mark A. Phuong Marisa C. W. Lim Daniel R. Wait Kevin C. Rowe Craig Moritz 《Biological journal of the Linnean Society. Linnean Society of London》2014,113(4):1136-1151
We apply an integrative taxonomy approach to delimit species of ground squirrels in the genus Otospermophilus because the diverse evolutionary histories of organisms shape the existence of taxonomic characters. Previous studies of mitochondrial DNA from this group recovered three divergent lineages within Otospermophilus beecheyi separated into northern, central, and southern geographical populations, with Otospermophilus atricapillus nested within the southern lineage of O. beecheyi. To further evaluate species boundaries within this complex, we collected additional genetic data (one mitochondrial locus, 11 microsatellite markers, and 11 nuclear loci), environmental data (eight bioclimatic variables), and morphological data (23 skull measurements). We used the maximum number of possible taxa (O. atricapillus, Northern O. beecheyi, Central O. beecheyi, and Southern O. beecheyi) as our operational taxonomic units (OTUs) and examined patterns of divergence between these OTUs. Phenotypic measures (both environmental and morphological) showed little differentiation among OTUs. By contrast, all genetic datasets supported the evolutionary independence of Northern O. beecheyi, although they were less consistent in their support for other OTUs as distinct species. Based on these data, we support the conclusions from a previous study that synonymized O. atricapillus with O. beecheyi, and we elevate the northern lineage of O. beecheyi to a separate species. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 1136–1151. 相似文献
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The holarctic genus Mesenchytraeus is one of the species-rich genera in the family Enchytraeidae. Changbai Mountain supports high diversity of Mesenchytraeus species, making it an ideal area to explore species boundaries. We explored species boundaries of Mesenchytraeus using an integrative approach. Morphological taxonomy recognized 10 species in this region, five of them new to science. In contrast, molecular species delimitation analyses showed that there are at least 16 species, 11 of them new to science. Clear genetic gaps were observed among species with high interspecific distances (10%–21.2%) and low intraspecific distances (0.2%–6.7%) based on uncorrected p-distance of the COI gene. Morphological species complex M. spermatoglomeratus consists of three species, M. spermatoglomeratus Zhang, Lu & Xie, 2018 sensu stricto, M. rijina sp. n., and M. manchu sp. n. The M. duodiverticulus complex consists of M. duodiverticulus sp. n. and M. similiduodiverticulus sp. n. The M. monodiverticulus complex consists of M. monodiverticulus Shen, Chen & Xie, 2012 sensu stricto, M. ngulen sp. n., M. zhenggulen sp. n., and M. fokulen sp. n. Further new species, distinguishable with morphological as well as molecular methods, are M. similigigachaetus sp. n., M. parvidiverticulus sp. n., M. digitalisdiverticulus sp. n., and M. infradiverticulus sp. n. Finally, we inferred the morphogenetic processes of spermathecae and sperm bundles, and filtrated some morphological characters which are useful to identify species. As the first attempt in this genus, our study provides an opportunity to discuss the currently used taxonomic criteria and acquire new ideas for the taxonomy of enchytraeids. 相似文献