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| Phrynoglossus myanhessei Köhler, Vargas, Than & Thammachoti, in Köhler, Vargas, Than, Schell, ... et Thammachoti, 2021. Photos by Gunther Köhler. |
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.
Key words: amplexus mode, bioacoustics, cryptic species diversity, Dicroglossidae, genome, Khorat Plateau, Myanmar, new species, Occidozyga, Phrynoglossus myanhessei sp. n., Thailand
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| Figure 6. Frogs of Phrynoglossus and Occidozyga in amplexus. (A) Phrynoglossus myanhessei n. sp., SMF 103797–98; (B) P. magnapustulosus, not collected; (C) Occidozyga lima, not collected (Magwe State, Myanmar); (D) O. lima, not collected (Roi Et province, Thailand). Photos by Gunther Köhler. |
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| Figure 11. Map indicating collecting localities of the Phrynoglossus species occurring in Indochina. Each symbol can represent one or more adjacent localities. Black squares: Phrynoglossus myanhessei n. sp.; black circles: P. martensii; green pentagons: P. cf. martensii; black triangles: P. magnapustulosus; white circles: additional specimens of Phrynoglossus from the FMNH, not examined by authors. |
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| Figure 10. Phrynoglossus myanhessei sp. n. in life. (A) Male holotype, SMF 103841; (B) male paratype, SMF 103840; (C) male paratype, SMF 103799; (D) female paratype, SMF 103798. Photos by Gunther Köhler. |
Phrynoglossus myanhessei Köhler, Vargas, Than & Thammachoti, sp. nov.
Diagnosis: A species of the genus Phrynoglossus as defined above that differs from all mainland Southeast Asian congeners by having (1) a large body size (males 22.0–27.4 mm; females 28.4–31.3 mm); (2) relatively small tympanum (ratio TYD/SVL 0.48–0.92); and (3) call duration of male advertisement call 85–114 ms. Phrynoglossus myanhessei differs from its congeners in Indochina (i.e., P. martensii and P. magnapustulosus) in the male advertisement call, most obvious in call duration (85–114 ms in P. myanhessei, 32–52 ms in P. martensii, 243–437 ms in P. magnapustulosus) and dominant frequency (2454–2885 Hz in P. myanhessei, 3338–3962 Hz in P. martensii, 3187–3790 Hz in P. magnapustulosus).
Etymology “Myan” is Myanmar’s abbreviated name and was chosen because this species is endemic to Myanmar as far as we know. “hessei” was chosen in recognition of the long-term support and funding of Senckenberg by the German State of Hesse. In combination, the species name myanhessei reflects the long-term productive collaboration of researchers from Hesse and Myanmar in the field of herpetology.
Natural history notes At the type locality, the specimens were collected at night in a patch of muddy grass area, partly open, partly covered by bushes and low trees. The frogs were sitting at the edge of small shallow temporary water bodies.
Gunther Köhler, Joseph Vargas, Ni Lar Than, Tilman Schell, Axel Janke, Steffen U. Pauls and Panupong Thammachoti. 2021. 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). Vertebrate Zoology. 71: 1-26. DOI: 10.3897/vertebrate-zoology.71.e60312
