Molecular taxonomy reveals an overlooked cryptic species of the tiger moth genus Murzinowatsonia Dubatolov (Lepidoptera, Arctiinae) from Sichuan, China

Estimates for the number of species in the sea vary by orders of magnitude. Molecular taxonomy can greatly speed up screening for diversity and evaluating species boundaries, while gaining insights into the biology of the species. DNA barcoding with a region of cytochrome oxidase 1 (COI) is now widely used as a first pass for molecular evaluation of diversity, as it has good potential for identifying cryptic species and improving our understanding of marine biodiversity. We present the results of a large scale barcoding effort for holothuroids (sea cucumbers). We sequenced 3048 individuals from numerous localities spanning the diversity of habitats in which the group occurs, with a particular focus in the shallow tropics (Indo-Pacific and Caribbean) and the Antarctic region. The number of cryptic species is much higher than currently recognized. The vast majority of sister species have allopatric distributions, with species showing genetic differentiation between ocean basins, and some are even differentiated among archipelagos. However, many closely related and sympatric forms, that exhibit distinct color patterns and/or ecology, show little differentiation in, and cannot be separated by, COI sequence data. This pattern is much more common among echinoderms than among molluscs or arthropods, and suggests that echinoderms acquire reproductive isolation at a much faster pace than other marine phyla. Understanding the causes behind such patterns will refine our understanding of diversification and biodiversity in the sea.

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Molecular taxonomy of endemic coastal Ligia isopods from the Hawaiian Islands: re-description of L. hawaiensis and description of seven novel cryptic species

PeerJ ◽

10.7717/peerj.7531 ◽

2019 ◽

Vol 7 ◽

pp. e7531

Author(s):

Carlos A. Santamaria

Keyword(s):

Cryptic Species ◽

Species Delimitation ◽

Molecular Taxonomy ◽

Hawaiian Islands ◽

Nuclear Gene ◽

Morphological Differentiation ◽

Taxonomic Revision ◽

Hawaiian Archipelago ◽

Genetic Lineages ◽

Molecular Characters

Past phylogeographic work has shown Ligia hawaiensis, a coastal isopod species endemic to the Hawaiian Islands, to be a paraphyletic complex of several highly genetically divergent yet morphologically cryptic lineages. Despite the need for a taxonomic revision of this species, the lack of morphological differentiation has proven an impediment to formally describe new Ligia species in the region. Molecular characters and species delimitation approaches have been successfully used to formally describe cryptic species in other crustacean taxa, suggesting they may aid taxonomic revisions of L. hawaiensis. Herein, various distance- and tree-based molecular species delimitation approaches are applied on a concatenated dataset comprised of both mitochondrial and nuclear gene sequences of L. hawaiensis and L. perkinsi, a terrestrial species endemic to the Hawaiian archipelago. Results of these analyses informed a taxonomic revision leading to the redescription of L. hawaiensis and the description of seven new cryptic species on the basis of molecular characters: L. dante, L. eleluensis, L. honu, L. kamehameha, L. mauinuiensis, L. pele, and L. rolliensis. These coastal Ligia species from the Hawaiian archipelago appear to be largely limited to single islands, where they appear largely constrained to volcanic rift zones suggesting allopatric events at local scales may drive diversification for poorly dispersing organisms in the Hawaiian coastlines. Additional work remains needed to fully assess the role of said events; however, the description of these novel species underscore their potential to aid in studies of local diversification of marine organisms in Hawai‘i. Lastly, this represents the first application of molecular taxonomic approaches to formally describe genetic lineages found in Ligia isopods as species, underscoring the promise these methods hold to taxonomic revisions in other species in the genus shown to harbor cryptic genetic lineages.

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How to describe a cryptic species? Practical challenges of molecular taxonomy

Frontiers in Zoology ◽

10.1186/1742-9994-10-59 ◽

2013 ◽

Vol 10 (1) ◽

pp. 59 ◽

Cited By ~ 166

Author(s):

Katharina M Jörger ◽

Michael Schrödl

Keyword(s):

Cryptic Species ◽

Molecular Taxonomy

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Unexpected species diversity within Japanese Mundochthonius pseudoscorpions (Pseudoscorpiones : Chthoniidae) and the necessity for improved species diagnosis revealed by molecular and morphological examination

Invertebrate Systematics ◽

10.1071/is17036 ◽

2018 ◽

Vol 32 (2) ◽

pp. 259 ◽

Cited By ~ 6

Author(s):

Hajime Ohira ◽

Shingo Kaneko ◽

Leanne Faulks ◽

Tadaaki Tsutsumi

Keyword(s):

Species Diversity ◽

Cryptic Species ◽

Nuclear Dna ◽

Phylogenetic Analyses ◽

Molecular Taxonomy ◽

Morphological Characteristics ◽

Rrna Genes ◽

Morphological Examination ◽

Species Classification ◽

Invertebrate Diversity

Using the complementary approaches of morphological and molecular taxonomy is essential to further our understanding of invertebrate diversity, including the identification of cryptic species. Although the species classification of a widespread group of arachnids, the pseudoscorpions, has been based on traditional diagnostic characters for a long time, recent taxonomic studies have suggested that some of these are unreliable for distinguishing species. Thus, the application of molecular taxonomy may be particularly useful in this group. Here, we performed molecular phylogenetic analyses and species delimitation analyses based on partial sequences of mitochondrial DNA cytochrome c oxidase I and nuclear DNA 18S rRNA genes to assess the taxonomy of species and the reliability of morphological characteristics for distinguishing species in the Japanese soil-dwelling genus Mundochthonius (Chthoniidae). Our results revealed the existence of seven major genetic clades, likely corresponding to three described species and four cryptic species. Although two described species, M. kiyoshii and M. itohi, were represented by single clades in the phylogenetic analysis, a third, M. japonicus, was composed of multiple clades, highlighting inconsistencies between phylogenetic relationships and current species classifications using traditional morphological diagnostics. This study exemplifies the need for further exploration of pseudoscorpion taxonomy and species diversity. In particular, detailed morphological examinations are expected to help determine differences among cryptic species.

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Identification of sibling species in the genus Eucyclops from water-bodies of Ukraine and Russia using crossbreeding studies

Ecology and Noospherology ◽

10.15421/031406 ◽

2014 ◽

Vol 25 (1-2) ◽

pp. 61-68 ◽

Cited By ~ 1

Author(s):

V. I. Monchenko ◽

L. P. Gaponova ◽

V. R. Alekseev

Keyword(s):

Cryptic Species ◽

River Basin ◽

Black Sea ◽

Species Complex ◽

River Basins ◽

Water Bodies ◽

Similar Species ◽

Basin Water ◽

Different Populations ◽

Baltic Sea Basin

Crossbreeding experiments were used to estimate cryptic species in water bodies of Ukraine and Russia because the most useful criterion in species independence is reproductive isolation. The problem of cryptic species in the genus Eucyclops was examined using interpopulation crosses of populations collected from Baltic Sea basin (pond of Strelka river basin) and Black Sea basin (water-reservoires of Dnieper, Dniester and Danube rivers basins). The results of reciprocal crosses in Eucyclops serrulatus-group are shown that E. serrulatus from different populations but from water bodies belonging to the same river basin crossed each others successfully. The interpopulation crosses of E. serrulatus populations collected from different river basins (Dnipro, Danube and Dniester river basins) were sterile. In this group of experiments we assigned evidence of sterility to four categories: 1) incomplete copulation or absence of copulation; 2) nonviable eggs; 3) absence of egg membranes or egg sacs 4) empty egg membranes. These crossbreeding studies suggest the presence of cryptic species in the E. serrulatus inhabiting ecologically different populations in many parts of its range. The same crossbreeding experiments were carries out between Eucyclops serrulatus and morphological similar species – Eucyclops macruroides from Baltic and Black Sea basins. The reciprocal crossings between these two species were sterile. Thus taxonomic heterogeneity among species of genus Eucyclops lower in E. macruroides than in E. serrulatus. The interpopulation crosses of E. macruroides populations collected from distant part of range were fertile. These crossbreeding studies suggest that E. macruroides species complex was evaluated as more stable than E. serrulatus species complex.

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Notes on the molecular taxonomy of the Proclossiana eunomia complex (Lepidoptera, Nymphalidae: Argynnini): analysis of DNA barcodes

Ukrainian Journal of Ecology ◽

10.15421/2018_206 ◽

2018 ◽

Vol 8 (1) ◽

pp. 222-232 ◽

Cited By ~ 1

Author(s):

R. V. Yakovlev ◽

N. A. Shapoval ◽

G. N. Kuftina ◽

A. V. Kulak ◽

S. V. Kovalev

Keyword(s):

Body Size ◽

Molecular Taxonomy ◽

Taxonomic Status ◽

Molecular Data ◽

Coi Gene ◽

Wing Pattern ◽

Molecular Approach ◽

Dna Barcodes ◽

Morphological Differences ◽

Proclossiana Eunomia

The Proclossiana eunomia (Esper, 1799) complex is currently composed of the several subspecies distributed throughout Palaearсtic region and North America. Despite the fact that some of the taxa have differences in wing pattern and body size, previous assumptions on taxonomy not supported by molecular data. Therefore, the identity of certain populations of this complex has remained unclear and the taxonomic status of several recently described taxa is debated. Here, we provide insights into systematics of some Palaearctic members of this group using molecular approach, based on the analysis of the barcoding fragment of the COI gene taking into account known morphological differences.

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