Saturday, June 27, 2020

[Herpetology • 2020] Dryophytes flaviventris • Yellow Sea mediated segregation between North East Asian Dryophytes Species

Dryophytes flaviventris Borzée & Min

in Borzée, Messenger, Chae, ... et Min, 2020.
Yellow-bellied Treefrog  | 노랑배청개구리 | 黄腹雨蛙  ||  DOI: 10.1371/journal.pone.0234299 

While comparatively few amphibian species have been described on the North East Asian mainland in the last decades, several species have been the subject of taxonomical debates in relation to the Yellow sea. Here, we sampled Dryophytes sp. treefrogs from the Republic of Korea, the Democratic People’s Republic of Korea and the People’s Republic of China to clarify the status of this clade around the Yellow sea and determine the impact of sea level change on treefrogs’ phylogenetic relationships. Based on genetics, call properties, adult morphology, tadpole morphology and niche modelling, we determined the segregated status species of D. suweonensis and D. immaculatus. We then proceeded to describe a new treefrog species, D. flaviventris sp. nov., from the central lowlands of the Republic of Korea. The new species is geographically segregated from D. suweonensis by the Chilgap mountain range and known to occur only in the area of Buyeo, Nonsan and Iksan in the Republic of Korea. While the Yellow sea is the principal element to the current isolation of the three clades, the paleorivers of the Yellow sea basin are likely to have been the major factor for the divergences within this clade. We recommend conducting rapid conservation assessments as these species are present on very narrow and declining ranges.

Fig 1. Summary map including ranges, call properties and a phylogenetic tree including the three focal clades of this study: Dryophytes suweonensis and Dryophytes flaviventris sp. nov. and D. immaculatus.
Ranges are drawn based on [Fei, et al., 2012; Borzée et al., 2017; Xie, 2017] and the base layer was created in ArcMap 10.6 (; ESRI, Redlands, USA). Sampling localities are also included. The waveforms are not bound to axes but are shown to highlight the difference in the number of pulses in the three species. The dark-blue line is the sea shore 21,000 years BP (redrawn from [Li, et al., 2014]) and the dotted lines are paleorivers [Yoo, et al., 2016].

Fig 3. Genetic structures of the Dryophytes immaculatus group. Phylogenetic tree based on ddRAD-seq polymorphic loci, highlighting the divergence of D. immaculatus from the other clades 1.02 mya, and the split between D. suweonensis and D. flaviventris c. 0.97 mya. The estimated divergence time (in mya) is illustrated, together with a 95% confidence interval bar and the posterior probabilities (BEAST2) for each clade.

Fig 10. Dryophytes flaviventris sp. nov.,
holotype (A, B, C), different individuals in life (D) and in amplexus (E).
The pictures of live individuals highlight the yellow coloration based on which the name was selected. The scale bar is for the holotype only.

Dryophytes flaviventris sp. nov. Borzée and Min, 2019

We name this new species Dryophytes flaviventris sp. nov. The specific name “flaviventris” is a masculine noun used in apposition and based on the Latin words “flavus” (yellow) and “ventris”, the genitive singular of venter (belly). The species name refers to the strong yellow marking on males, and the yellow hues on females (Fig 10). We suggest the English vernacular name “Yellow-bellied Treefrog”, the Korean common name 노랑배청개구리and the Chinese common name 黄腹雨蛙.

We recommend D. flaviventris, D. suweonensis and D. immaculatus to be collectively referred as the “Dryophytes immaculatus group” based on the seniority of the species description [Boettger, 1888], in opposition to the D. japonicus group [Hua et al., 2009; Duellman et al., 2016]. To clarify the distinction with the other clades, we recommend the use of “Chinese immaculate treefrog” for D. immaculatus (无斑雨蛙 in Chinese and민무늬청개구리 in Korean) as a way to distinguish with populations of D. japonicus occurring in the country [Fei et al., 2012], and for which taxonomy is yet unresolved [Dufresnes, et al., 2016]. The taxonomy of D. suweonensis is now likely to be stable, 수원청개구리 in Korean and 水原雨蛙 in Chinese.

Amaël Borzée, Kevin R. Messenger, Shinhyeok Chae, Desiree Andersen, Jordy Groffen,Ye Inn Kim, Junghwa An, Siti N. Othman, Kyongsin Ri, Tu Yong Nam, Yoonhyuk Bae, Jin-Long Ren, Jia-Tang Li, Ming-Feng Chuang, Yoonjung Yi, Yucheol Shin, Taejoon Kwon, Yikweon Jang and Mi-Sook Min. 2020. Yellow Sea mediated segregation between North East Asian Dryophytes Species. PLoS ONE. 15(6): e0234299. DOI: 10.1371/journal.pone.0234299