A revised classification of the family Dasyatidae (Chondrichthyes: Myliobatiformes) based on new morphological and molecular insights

Abstract

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.

A Review of the Mitogenomic Phylogeny of the Chondrichthyes

“…In general, for example, four groups are recognized, the stingrays (Myliobatiformes), electric rays (Torpediniformes), sawfish (Pristiformes), skates, and guitarfish (Rajiformes), although the relationships among these groups are still undefined [21][22][23][24][25]. In addition, a number of new species of ray have been described recently, and the radiation patterns of this group have been better identified [25][26][27][28][29].…”

Introductory Chapter: The Elasmobranchs as a Fishery Resource

“…In recent years, there have been considerable eforts in the Asian region, with wide-ranging phylogenetic and morphological inferences [5,6], as well as the description of new species [7,11,15] and the reinstatement of a number of families [8].…”

“…The rays include 5 orders, 20 families, and around 574 species [9,10]. In recent years, the application of molecular tools in combination with morphological analyses has led to a signiicant increase in the known diversity of elasmobranch species [6,11]. One of the most important molecular tools is the DNA barcode [12], which provides a rapid and reliable approach for the identiication of taxonomic groups, especially those which may contain cryptic species, that is, taxa that are morphologically indistinguishable, but genetically distinct, highlighting the need for systematic reviews [7,13,14].…”

“…Recent studies of elasmobranch diversity have focused primarily on the Asian domain and have included the description of new species [5,7,15], the re-organization of some families [11], and the re-establishment of others [8]. All these diversities have been "discovered," thanks to the systematic combination of molecular and morphological approaches, with molecular tools being especially useful for the delimitation of groups or species thought to contain cryptic diversity [16,17] or that need internal review [18].…”

Captura incidental de la raya Hypanus americanus (Elasmobranchii) en la pesca de arrastre de camaron en la region suroriental de Cuba

“…En estudios realizados sobre las pesquerías en el Caribe se ha planteado que el género Dasyatis es susceptible de ser extraído frecuentemente en la pesca de red de arrastre (Caldas et al, 2009) en particular, como fauna acompañante en la pesca de camarón (Acevedo et al, 2007). En un estudio reciente, Last et al (2016) plantean que algunas especies de la familia Dasyatidae deben pasar a formar parte de otro género, tal es el caso de la especie abordada en el presente estudio, Dasyatis americana, que fue transferida al género Hypanus.…”