Latest Articles from Vertebrate Zoology Latest 3 Articles from Vertebrate Zoology https://vertebrate-zoology.arphahub.com/ Fri, 29 Mar 2024 15:20:41 +0200 Pensoft FeedCreator https://vertebrate-zoology.arphahub.com/i/logo.jpg Latest Articles from Vertebrate Zoology https://vertebrate-zoology.arphahub.com/ Unnecessary splitting of genus-level clades reduces taxonomic stability in amphibians https://vertebrate-zoology.arphahub.com/article/114285/ Vertebrate Zoology 74: 249-277

DOI: 10.3897/vz.74.e114285

Authors: Stephen Mahony, Rachunliu G. Kamei, Rafe M. Brown, Kin Onn Chan

Abstract: Abstract Although the differentiation of clades at the species level is usually based on a justifiable and testable conceptual framework, the demarcation of supraspecific boundaries is less objective and often subject to differences of opinion. The increased availability of large-scale phylogenies has in part promulgated a practice of what we consider excessively splitting clades at the “genus” level. Many of these new genus-level splits are predicated on untenable supporting evidence (e.g., weakly supported phylogenies and purportedly “diagnostic” but actually variable, non-exclusive, or otherwise problematic opposing character state differences) without careful consideration of the effects on downstream applications. As case studies, we critically evaluate several recent examples of splitting established monophyletic genera in four amphibian families that resulted in the creation/elevation of 20 genus-level names (Dicroglossidae: Phrynoglossus, Oreobatrachus, Frethia split from Occidozyga; Microhylidae: Nanohyla split from Microhyla; Ranidae: Abavorana, Amnirana, Chalcorana, Humerana, Hydrophylax, Indosylvirana, Papurana, Pulchrana, Sylvirana split from Hylarana; Rhacophoridae: Tamixalus, Vampyrius, Leptomantis, Zhangixalus split from Rhacophorus, Rohanixalus split from Feihyla, Orixalus split from Gracixalus, and Taruga split from Polypedates), and also address the taxonomic status of the monotypic genus Pterorana relative to Hylarana. We reassess the original claims of diagnosability and justifications for splitting and argue that in many cases, the generic splitting of clades is not only unnecessary but also destabilizes amphibian taxonomy, leading to a host of downstream issues that affect categories of the user community (stakeholders such as taxonomists, conservationists, evolutionary biologists, biogeographers, museum curators, educators, and the lay public). As an alternative, we advocate for the use of the subgenus rank in some cases, which can be implemented to establish informative partitions for future research without compromising on information content, while avoiding gratuitous (and often transient) large-scale binomial (genus-species couplet) rearrangements. We encourage taxonomists to consider the actual needs and interests of the larger non-taxonomic end-user community who fund the majority of taxonomic research, and who require a system that remains reasonably stable and is relatively intuitive, without the need for inaccessible laboratory equipment or advanced technical scientific knowledge to identify amphibian species to the genus level.

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Review Article Tue, 26 Mar 2024 17:07:56 +0200
The curious case of Charles Darwin’s frog, Rana charlesdarwini Das, 1998: Phylogenetic position and generic placement, with taxonomic insights on other minervaryan frogs (Dicroglossidae: Minervarya) in the Andaman and Nicobar Archipelago https://vertebrate-zoology.arphahub.com/article/79496/ Vertebrate Zoology 72: 169-199

DOI: 10.3897/vz.72.e79496

Authors: Sonali Garg, Sivaperuman Chandrakasan, G. Gokulakrishnan, C. Gopika, Indraneil Das, S. D. Biju

Abstract: Since the description of Charles Darwin’s frog as Rana charlesdarwini in 1998, its generic placement has been a taxonomic enigma. Subsequent studies first transferred this species to the dicroglossid genus Limnonectes, and then considered it as a ceratobatrachid of the genus Ingerana, which has since been moved to the family Dicroglossidae. However, recent works have doubted this generic placement and also suggested the possibility of its sister relationship with the genus Liurana, within Ceratobatrachidae. Nonetheless, there have been no detailed investigations to ascertain the generic placement of this taxon by confirming its phylogenetic position or using integrative taxonomic approaches. Here, we provide the first molecular assessment of Ingerana charlesdarwini based on mitochondrial and nuclear DNA and reveal that it is nested in the dicroglossid genus Minervarya. A member of the Minervarya andamanensis species group, Minervarya charlesdarwini comb. nov. is sister taxon to M. andamanensis and shows relatively shallow genetic distances (2.8–3.6%) in the 16S gene. Both species are widely distributed, occur sympatrically, and exhibit high morphological variations, leading to long-standing confusions with other dicroglossid frogs reported from the region. Our combined morphological and molecular studies on dicroglossid frogs sampled across the known ranges of these species suggest that reports of Limnonectes doriae (Boulenger, 1887) and L. hascheanus (Stoliczka, 1870) from the Andamans are misidentifications of the former two, pointing to the absence of genus Limnonectes from the Andaman Islands. Our study also reveals the novel record of Minervarya agricola from the Andamans, a species that appears to have been confused with Fejervarya limnocharis and Minervarya keralensis in the literature and misidentified museum specimens, and is found to be widely distributed across these islands. We further find another congener from the Nicobar group of Islands, M. nicobariensis, to be closely related to M. charlesdarwini. Similar to the case of Andaman dicroglossids, our work emphasises on the need for further studies to ascertain the taxonomic identities and generic placement of Minervarya and Limnonectes species reported from the Nicobars.

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Research Article Tue, 10 May 2022 11:58:18 +0300
A taxonomic revision of the genus Phrynoglossus in Indochina with the description of a new species and comments on the classification within Occidozyginae (Amphibia, Anura, Dicroglossidae) https://vertebrate-zoology.arphahub.com/article/60312/ Vertebrate Zoology 71: 1-26

DOI: 10.3897/vz.71.e60312

Authors: Gunther Köhler, Joseph Vargas, Ni Lar Than, Tilman Schell, Axel Janke, Steffen U. Pauls, Panupong Thammachoti

Abstract: We revise the frogs of the genus Phrynoglossus from Indochina based on data of external morphology, bioacoustics and molecular genetics. The results of this integrative study provide evidence for the recognition of three distinct species, one of which we describe as new. Phrynoglossus martensii has a vast geographic distribution from central and southern Thailand across southern China to Vietnam, Laos, and Cambodia. Phrynoglossus myanhessei sp. nov. is distributed in central Myanmar whereas Phrynoglossus magnapustulosus is restricted to the Khorat Plateau, Thailand. These three species occur in allopatry and differ in their mating calls, external morphology, and in genetic distances of the 16S gene of 3.8–5.9%. Finally, we discuss and provide evolutionary evidence for the recognition of Phrynoglossus as a genus distinct from Occidozyga. Members of both genera form reciprocal monophyletic groups in our analyses of mtDNA data (16S) and are well differentiated from each other in morphology and ecology. Furthermore, they differ in the amplexus mode with Phrynoglossus having an inguinal amplexus whereas it is axillary in Occidozyga. We further provide a de novo draft genome of the holotype based on short-read sequencing technology to a coverage of 25-fold. This resource will permanently link the genetic characterization of the species to the name-bearing type specimen.

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Research Article Fri, 26 Feb 2021 12:05:06 +0200