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Giuseppe Marramà - One of the best experts on this subject based on the ideXlab platform.
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Egg preservation in an Eocene stingray (Myliobatiformes, Dasyatidae) from Italy
Journal of vertebrate paleontology, 2019Co-Authors: Federico Fanti, Gabriele Mazzuferi, Giuseppe MarramàAbstract:Known since the 16th century, Pesciara di Bolca in Italy represents one of the most intensively sampled Eocene marine localities, providing an unparalleled window on the early evolution of modern m...
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Egg preservation in an Eocene stingray (Myliobatiformes, Dasyatidae) from Italy
2019Co-Authors: Federico Fanti, Gabriele Mazzuferi, Giuseppe MarramàAbstract:Egg preservation in an Eocene stingray (Myliobatiformes, Dasyatidae) from Ital
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Reappraisal of the Eocene whiptail stingrays (Myliobatiformes, Dasyatidae) of the Bolca Lagerstätte, Italy.
Zoologica scripta, 2018Co-Authors: Giuseppe Marramà, Gavin J. P. Naylor, Giorgio Carnevale, Jürgen KriwetAbstract:The Eocene whiptail stingrays of the family Dasyatidae from the Bolca Lagerstatte, NE Italy, are revised herein in detail. The analysis of the anatomical and morphometric features allows us to identify the species "Dasyatis" zigni (Molin, 1861) as a junior synonym of "D." muricatus (Volta, 1796), and to assign it to the new genus Tethytrygon gen. n. This new taxon exhibits a unique combination of features (e.g., rhombic disc wider than long, elongated tail folds fail to reach the tip of the tail, thorns absent, single serrated tail sting, "caniniform" teeth on upper jaw, tooth crown ornamentation absent, 175-179 vertebrae, 108-117 pectoral radials, 24-27 pelvic radials and other features of clasper anatomy) that clearly support its attribution to the subfamily Neotrygoninae of the stingray family Dasyatidae. The morphological and phylogenetic affinities of Tethytrygon gen. n. with the living neotrygonines (Neotrygon and Taeniura) suggest a close association of this taxon with the tropical shallow-water habitats hypothesized for the Bolca palaeoenvironment during the early Eocene. Moreover, the analysis of the fossil occurrences of the neotrygonines provides new insights into the role of the Tethys for the origin and evolutionary history of certain whiptail stingrays.
Philippe Borsa - One of the best experts on this subject based on the ideXlab platform.
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neotrygon vali a new blue spotted maskray complex myliobatoidei Dasyatidae
bioRxiv, 2017Co-Authors: Philippe BorsaAbstract:The blue-spotted maskray from Guadalcanal Island (Solomon archipelago) is distinct by its colour patterns from Neotrygon kuhlii with which it was previously confused, and belongs to a genetic lineage clearly separate from all other known species in the genus Neotrygon. It is here described as a new species, Neotrygon vali sp. nov., on the basis of its nucleotide sequence at the cytochrome oxidase 1 (CO1) gene locus. It is diagnosed from all other known species in the genus Neotrygon by the possession of nucleotide T at nucleotide site 420 and nucleotide G at nucleotide site 522 of the CO1 gene.
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Comments on “Annotated checklist of the living sharks, batoids and chimaeras (Chondrichthyes) of the world, with a focus on biogeographical diversity” (Weigmann, 2016)
Journal of Fish Biology, 2017Co-Authors: Philippe BorsaAbstract:S. Weigmann recently synonymized the fine-spotted leopard whipray Himantura tutul (Myliobatoidei: Dasyatidae) with the darkspotted whipray Himantura uarnak, and the New Caledonian maskray Neotrygon trigonoides (Myliobatoidei: Dasyatidae) with the blue-spotted maskray Neotrygon kuhlii. However, Himantura tutul is genetically distinct, reproductively isolated, and partly distinct morphologically from the leopard whipray Himantura leoparda with which it was previously confused, and both are morphologically and genetically distinct from H. uarnak. Likewise, N. trigonoides is a genetically and morphologically distinct species from the Coral Sea and possibly the adjacent Vanuatu and Fiji archipelagoes.
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Comment on 'Annotated checklist of the living sharks, batoids and chimaeras (Chondrichthyes) of the world, with a focus on biogeographical diversity by Weigmann (2016)'.
Journal of fish biology, 2016Co-Authors: Philippe BorsaAbstract:S. Weigmann recently synonymized the fine-spotted leopard whipray Himantura tutul (Myliobatoidei: Dasyatidae) with the darkspotted whipray Himantura uarnak, and the New Caledonian maskray Neotrygon trigonoides (Myliobatoidei: Dasyatidae) with the blue-spotted maskray Neotrygon kuhlii. However, Himantura tutul is genetically distinct, reproductively isolated, and partly distinct morphologically from the leopard whipray Himantura leoparda with which it was previously confused, and both are morphologically and genetically distinct from H. uarnak. Likewise, N. trigonoides is a genetically and morphologically distinct species from the Coral Sea and possibly the adjacent Vanuatu and Fiji archipelagoes.
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Species boundaries in the Himantura uarnak species complex (Myliobatiformes: Dasyatidae).
Molecular phylogenetics and evolution, 2012Co-Authors: Irma S. Arlyza, Kang-ning Shen, Dedy Duryadi Solihin, Dedi Soedharma, Patrick Berrebi, Philippe BorsaAbstract:Samples of the ‘Himantura uarnak’ species complex (H. leoparda, H. uarnak, H. undulata under their current definitions), mostly from the Coral Triangle, were analyzed using nuclear markers and mitochondrial DNA sequences. Genotypes at five intron loci showed four reproductively isolated clusters of individuals. The COI sequences showed four major mitochondrial lineages, each diagnostic of a cluster as defined by nuclear markers. No mitochondrial introgression was detected. The average Kimura-2 parameter nucleotide distance separating clades was 0.061–0.120 (net: 0.055–0.114), while the distance separating individuals within a clade was 0.002–0.008. Additional, partial cytochrome-b gene sequences were used to link these samples with previously published sequences of reference specimens of the three nominal species. One of the clusters was identified as H. undulata and another one, as H. uarnak, while two cryptic species were uncovered within the recently-described H. leoparda, challenging the current morphology-based taxonomy of species within the H. uarnak species complex.
Gavin J. P. Naylor - One of the best experts on this subject based on the ideXlab platform.
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Reappraisal of the Eocene whiptail stingrays (Myliobatiformes, Dasyatidae) of the Bolca Lagerstätte, Italy.
Zoologica scripta, 2018Co-Authors: Giuseppe Marramà, Gavin J. P. Naylor, Giorgio Carnevale, Jürgen KriwetAbstract:The Eocene whiptail stingrays of the family Dasyatidae from the Bolca Lagerstatte, NE Italy, are revised herein in detail. The analysis of the anatomical and morphometric features allows us to identify the species "Dasyatis" zigni (Molin, 1861) as a junior synonym of "D." muricatus (Volta, 1796), and to assign it to the new genus Tethytrygon gen. n. This new taxon exhibits a unique combination of features (e.g., rhombic disc wider than long, elongated tail folds fail to reach the tip of the tail, thorns absent, single serrated tail sting, "caniniform" teeth on upper jaw, tooth crown ornamentation absent, 175-179 vertebrae, 108-117 pectoral radials, 24-27 pelvic radials and other features of clasper anatomy) that clearly support its attribution to the subfamily Neotrygoninae of the stingray family Dasyatidae. The morphological and phylogenetic affinities of Tethytrygon gen. n. with the living neotrygonines (Neotrygon and Taeniura) suggest a close association of this taxon with the tropical shallow-water habitats hypothesized for the Bolca palaeoenvironment during the early Eocene. Moreover, the analysis of the fossil occurrences of the neotrygonines provides new insights into the role of the Tethys for the origin and evolutionary history of certain whiptail stingrays.
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Three new stingrays (Myliobatiformes: Dasyatidae) from the Indo-West Pacific.
Zootaxa, 2016Co-Authors: William T. White, Gavin J. P. NaylorAbstract:Three undescribed stingrays were discovered as part of a broader revision of the family Dasyatidae that formed part of the Chondrichthyan Tree of Life project. This research forms part of a sequence of papers on rays aimed at describing unnamed species for inclusion in a multi-authored guide to rays of the world. The first part of this series focused on a redefinition of genera of the family Dasyatidae. The new Indo–West Pacific taxa are represented by separate genera from three dasyatid subfamilies: Himantura australis sp. nov. (northern Australia and Papua New Guinea), Taeniura lessoni sp. nov. (Melanesia) and Telatrygon biasa sp. nov. (Indo–Malay Archipelago). Himantura australis sp. nov., which belongs to a complex of four closely related reticulate whiprays, differs subtly from its congeners in coloration, morphometrics and distribution. Taeniura lessoni sp. nov. is the second species in a genus containing the widely-distributed T. lymma , which is possibly the most abundant stingray in shallow coral-reef habitats of the Indo–Pacific, with the new species apparently restricted to Melanesia . Taeniura lessoni sp. nov. is distinguishable by the absence of a distinctive pair of vivid blue longitudinal stripes on the dorsolateral edges of the tail which is one of the most distinctive features of T. lymma . Telatrygon biasa sp. nov. belongs to a small, recently designated genus of stingrays represented by four species in the tropical Indo-West Pacific. Telatrygon biasa sp. nov. differs from these species in morphometrics. The new species differs markedly from T. zugei in its NADH2 sequence. Telatrygon crozieri is resurrected as a valid northern Indian Ocean representative of the T. zugei complex.
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A revised classification of the family Dasyatidae (Chondrichthyes: Myliobatiformes) based on new morphological and molecular insights.
Zootaxa, 2016Co-Authors: Gavin J. P. Naylor, B. Mabel Manjaji-matsumotoAbstract:The higher-level taxonomy of the stingrays (Dasyatidae) has never been comprehensively reviewed. Recent phylogenetic studies, supported by morphological data, have provided evidence that the group is monophyletic and consists of four major subgroups, the subfamilies Dasyatinae, Neotrygoninae, Urogymninae and Hypolophinae. A morphologically based review of 89 currently recognised species, undertaken for a guide to the world’s rays, indicated that most of the currently recognised dasyatid genera are not monophyletic groups. These findings were supported by molecular analyses using the NADH2 gene for about 77 of these species, and this topology is supported by preliminary analyses base on whole mitochondrial genome comparisons. These molecular analyses, based on data generated from the Chondrichthyan Tree of Life project, are the most taxon-rich data available for this family. Material from all of the presently recognised genera ( Dasyatis, Pteroplatytrygon and Taeniurops [Dasyatinae]; Neotrygon and Taeniura [Neotrygoninae]; Himantura and Urogymnus [Urogymninae]; and Makararaja and Pastinachus [Hypolophinae]), are included and their validity largely supported. Urogymnus and the two most species rich genera, Dasyatis and Himantura , are not considered to be monophyletic and were redefined based on external morphology. Seven new genus-level taxa are erected ( Megatrygon and Telatrygon [Dasyatinae]; Brevitrygon, Fluvitrygon, Fontitrygon, Maculabatis and Pateobatis [Urogymninae], and an additional three ( Bathytoshia , Hemitrygon and Hypanus [Dasyatinae]) are resurrected from the synonymy of Dasyatis . The monotypic genus Megatrygon clustered with ‘amphi-American Himantura ’ outside the Dasyatidae, and instead as the sister group of the Potamotrygonidae and Urotrygonidae. Megatrygon is provisionally retained in the Dasyatinae pending further investigation of its internal anatomy. The morphologically divergent groups, Bathytoshia and Pteroplatytrygon, possibly form a single monophyletic group so further investigation is needed to confirm the validity of Pteroplatytrygon . A reclassification of the family Dasyatidae is provided and the above taxa are defined based on new morphological data.
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An annotated checklist of the chondrichthyans of Taiwan.
Zootaxa, 2013Co-Authors: David A. Ebert, Gavin J. P. Naylor, William T. White, Kazuhiro Nakaya, Bernard Séret, Nicolas Straube, Marcelo R. De ,carvalhoAbstract:An annotated checklist of chondrichthyan fishes (sharks, batoids, and chimaeras) occurring in Taiwanese waters is presented. The checklist is the result of a biodiversity workshop held in Mach 2012 as well as on-going systematic revisions by the authors. The chondrichthyan fauna of Taiwan is one of the richest in the world with the number of species totaling 181, comprising 52 families and 98 genera. It includes 31 families, 64 genera, and 119 species of sharks, 19 families, 31 genera, and 58 species of batoids, and 2 families, 3 genera, and 4 species of chimaeras. The most species-rich families are the Carcharhinidae with 22 species followed by the Scyliorhinidae with 17. The most species-rich batoid families are the Dasyatidae with 11 species and and the Rajidae with 10. Verified voucher materialis provided for each species where available and potential taxonomic issues are high-lighted when applicable. This represents the first detailed, evidence-based checklist of chondrichthyans from Taiwanese waters in over 40 years.
William T. White - One of the best experts on this subject based on the ideXlab platform.
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An annotated checklist of the chondrichthyans of Papua New Guinea.
Zootaxa, 2018Co-Authors: William T. White, Alfred Ko’ouAbstract:An annotated checklist of the chondrichthyan fishes (sharks, rays, and chimaeras) of Papua New Guinean waters is herein presented. The checklist is the result of a large biodiversity study on the chondrichthyan fauna of Papua New Guinea between 2013 and 2017. The chondrichthyan fauna of Papua New Guinea has historically been very poorly known due to a lack of baseline information and limited deepwater exploration. A total of 131 species, comprising 36 families and 68 genera, were recorded. The most speciose families are the Carcharhinidae with 29 species and the Dasyatidae with 23 species. Verified voucher material from various biological collections around the world are provided, with a total of 687 lots recorded comprising 574 whole specimens, 128 sets of jaws and 21 sawfish rostra. This represents the first detailed, verified checklist of chondrichthyans from Papua New Guinean waters.
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Three new stingrays (Myliobatiformes: Dasyatidae) from the Indo-West Pacific.
Zootaxa, 2016Co-Authors: William T. White, Gavin J. P. NaylorAbstract:Three undescribed stingrays were discovered as part of a broader revision of the family Dasyatidae that formed part of the Chondrichthyan Tree of Life project. This research forms part of a sequence of papers on rays aimed at describing unnamed species for inclusion in a multi-authored guide to rays of the world. The first part of this series focused on a redefinition of genera of the family Dasyatidae. The new Indo–West Pacific taxa are represented by separate genera from three dasyatid subfamilies: Himantura australis sp. nov. (northern Australia and Papua New Guinea), Taeniura lessoni sp. nov. (Melanesia) and Telatrygon biasa sp. nov. (Indo–Malay Archipelago). Himantura australis sp. nov., which belongs to a complex of four closely related reticulate whiprays, differs subtly from its congeners in coloration, morphometrics and distribution. Taeniura lessoni sp. nov. is the second species in a genus containing the widely-distributed T. lymma , which is possibly the most abundant stingray in shallow coral-reef habitats of the Indo–Pacific, with the new species apparently restricted to Melanesia . Taeniura lessoni sp. nov. is distinguishable by the absence of a distinctive pair of vivid blue longitudinal stripes on the dorsolateral edges of the tail which is one of the most distinctive features of T. lymma . Telatrygon biasa sp. nov. belongs to a small, recently designated genus of stingrays represented by four species in the tropical Indo-West Pacific. Telatrygon biasa sp. nov. differs from these species in morphometrics. The new species differs markedly from T. zugei in its NADH2 sequence. Telatrygon crozieri is resurrected as a valid northern Indian Ocean representative of the T. zugei complex.
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An annotated checklist of the chondrichthyans of Taiwan.
Zootaxa, 2013Co-Authors: David A. Ebert, Gavin J. P. Naylor, William T. White, Kazuhiro Nakaya, Bernard Séret, Nicolas Straube, Marcelo R. De ,carvalhoAbstract:An annotated checklist of chondrichthyan fishes (sharks, batoids, and chimaeras) occurring in Taiwanese waters is presented. The checklist is the result of a biodiversity workshop held in Mach 2012 as well as on-going systematic revisions by the authors. The chondrichthyan fauna of Taiwan is one of the richest in the world with the number of species totaling 181, comprising 52 families and 98 genera. It includes 31 families, 64 genera, and 119 species of sharks, 19 families, 31 genera, and 58 species of batoids, and 2 families, 3 genera, and 4 species of chimaeras. The most species-rich families are the Carcharhinidae with 22 species followed by the Scyliorhinidae with 17. The most species-rich batoid families are the Dasyatidae with 11 species and and the Rajidae with 10. Verified voucher materialis provided for each species where available and potential taxonomic issues are high-lighted when applicable. This represents the first detailed, evidence-based checklist of chondrichthyans from Taiwanese waters in over 40 years.
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Two new stingrays (Chondrichthyes: Dasyatidae) from the eastern Indonesian Archipelago.
Zootaxa, 2013Co-Authors: William T. WhiteAbstract:Two new stingrays, Dasyatis longicauda sp. nov. and Himanturajavaensis sp. nov., are described from material collected in the eastern Indonesian Archipelago. These species, which are both relatively small stingrays (both probably smaller than 40 cm DW), have been confused with closest relatives in the region. Dasyatis longicauda sp. nov., known from West Papua, differs from its congener, the Australian endemic D. fluviorum, in having a slightly lower vertebral count, lower pectoral-radial count, a longer tail, larger and less numerous thorns along the mid-disc and tail, as well as a different CO1 Barcode. Himantura javaensis sp. nov., known only from southern Java (near Cilacap), belongs to a complex of small whiprays which also includes another Indonesian species, H. walga. Apart from major differences in squamation and a different CO1 Barcode, Himantura javaensis is more brownish in coloration, has more vertebrae, a longer tail, smaller eye and orbit, more posteriorly positioned sting, shorter adult claspers, shorter pelvic fin, and differs in various measurements around the head.
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Phylogeography of the Indo-West Pacific maskrays (Dasyatidae, Neotrygon): a complex example of chondrichthyan radiation in the Cenozoic.
Ecology and evolution, 2012Co-Authors: Melody Puckridge, William T. White, Nikos AndreakisAbstract:Maskrays of the genus Neotrygon (Dasyatidae) have dispersed widely in the Indo-West Pacific being represented largely by an assemblage of narrow-ranging coastal endemics. Phylogenetic reconstruction methods reproduced nearly identical and statistically robust topologies supporting the monophyly of the genus Neotrygon within the family Dasyatidae, the genus Taeniura being consistently basal to Neotrygon, and Dasyatis being polyphyletic to the genera Taeniurops and Pteroplatytrygon. The Neotrygon kuhlii complex, once considered to be an assemblage of color variants of the same biological species, is the most derived and widely dispersed subgroup of the genus. Mitochondrial (COI, 16S) and nuclear (RAG1) phylogenies used in synergy with molecular dating identified paleoclimatic fluctuations responsible for periods of vicariance and dispersal promoting population fragmentation and speciation in Neotrygon. Signatures of population differentiation exist in N. ningalooensis and N. annotata, yet a large-scale geological event, such as the collision between the Australian and Eurasian Plates, coupled with subsequent sea-level falls, appears to have separated a once homogeneous population of the ancestral form of N. kuhlii into southern Indian Ocean and northern Pacific taxa some 4–16 million years ago. Repeated climatic oscillations, and the subsequent establishment of land and shallow sea connections within and between Australia and parts of the Indo-Malay Archipelago, have both promoted speciation and established zones of secondary contact within the Indian and Pacific Ocean basins.
Kar-hoe Loh - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Molecular and Morphological Analyses Reveal Phylogenetic Relationships of Stingrays Focusing on the Family Dasyatidae
2016Co-Authors: Kean Chong Lim, Phaik-eem Lim, Ving Ching Chong, Kar-hoe LohAbstract:Elucidating the phylogenetic relationships of the current but problematic Dasyatidae (Order Myliobatiformes) was the first priority of the current study. Here, we studied three molecular gene markers of 43 species (COI gene), 33 species (ND2 gene) and 34 species (RAG1 gene) of stingrays to draft out the phylogenetic tree of the order. Nine character states were identified and used to confirm the molecularly constructed phylogenetic trees. Eight or more clades (at different hierarchical level) were identified for COI, ND2 and RAG1 genes in the Myliobatiformes including four clades containing members of the present Dasyatidae, thus rendering the latter non-monophyletic. The uncorrected p-distance between these four ‘Dasytidae ’ clades when compared to the distance between formally known families con-firmed that these four clades should be elevated to four separate families. We suggest a re-vision of the present classification, retaining the Dasyatidae (Dasyatis and Taeniurops species) but adding three new families namely, Neotrygonidae (Neotrygon and Taeniura species), Himanturidae (Himantura species) and Pastinachidae (Pastinachus species). Our result indicated the need to further review the classification of Dasyatis microps. By resolv-ing the non-monophyletic problem, the suite of nine character states enables the natural classification of the Myliobatiformes into at least thirteen families based on morphology
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Molecular and morphological analyses reveal phylogenetic relationships of stingrays focusing on the family Dasyatidae (Myliobatiformes).
PloS one, 2015Co-Authors: Kean Chong Lim, Phaik-eem Lim, Ving Ching Chong, Kar-hoe LohAbstract:Elucidating the phylogenetic relationships of the current but problematic Dasyatidae (Order Myliobatiformes) was the first priority of the current study. Here, we studied three molecular gene markers of 43 species (COI gene), 33 species (ND2 gene) and 34 species (RAG1 gene) of stingrays to draft out the phylogenetic tree of the order. Nine character states were identified and used to confirm the molecularly constructed phylogenetic trees. Eight or more clades (at different hierarchical level) were identified for COI, ND2 and RAG1 genes in the Myliobatiformes including four clades containing members of the present Dasyatidae, thus rendering the latter non-monophyletic. The uncorrected p-distance between these four ‘Dasytidae’ clades when compared to the distance between formally known families confirmed that these four clades should be elevated to four separate families. We suggest a revision of the present classification, retaining the Dasyatidae (Dasyatis and Taeniurops species) but adding three new families namely, Neotrygonidae (Neotrygon and Taeniura species), Himanturidae (Himantura species) and Pastinachidae (Pastinachus species). Our result indicated the need to further review the classification of Dasyatis microps. By resolving the non-monophyletic problem, the suite of nine character states enables the natural classification of the Myliobatiformes into at least thirteen families based on morphology.
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Plots of canonical scores derived from forward stepwise discriminant analysis of morphometric measurements of four stingray families.
2015Co-Authors: Kean Chong Lim, Phaik-eem Lim, Ving Ching Chong, Kar-hoe LohAbstract:Squares = Dasyatidae; triangles = Neotrygonidae; crosses = Himanturidae; circles = Pastinachidae.
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Range of uncorrected p-distances among the four clusters in the Dasyatidae (sensu Carpenter & Niem, 1999) based on COI, ND2 and RAG1 genes.
2015Co-Authors: Kean Chong Lim, Phaik-eem Lim, Ving Ching Chong, Kar-hoe LohAbstract:Range of uncorrected p-distances among the four clusters in the Dasyatidae (sensu Carpenter & Niem, 1999) based on COI, ND2 and RAG1 genes.
