Diploderma, Hallowell, 1861

Wang, Kai, Che, Jing, Lin, Simin, Deepak, V., Aniruddha, Datta-Roy, Jiang, Ke, Jin, Jieqiong, Chen, Hongman & Siler, Cameron D., 2019, Multilocus phylogeny and revised classification for mountain dragons of the genus Japalura s. l. (Reptilia: Agamidae: Draconinae) from Asia, Zoological Journal of the Linnean Society 185, pp. 246-267 : 263

Diploderma

Recently, Ananjeva et al. (2007) described a new species of Japalura , J. ngoclinensis , on the basis of three female specimens collected from the central highlands of Vietnam, far outside of the range of Japalura s.l. recognized at the time. Although there are no genetic data available for the species, we can assign it to the genus Diploderma based on our revised morphological diagnosis. The issue that remains is in regard to the taxonomic validity of D. ngoclinense . Despite the fact that the type specimens of the species are morphologically most similar to D. splendidum , a brief comparison was made to the latter species using one morphological characteristic only ( Ananjeva et al., 2017). The authors argued that the new species differs from D. splendidum by the absence of a transverse gular fold ( Ananjeva et al., 2017). However, based on the photographs of the type series in the original description, all type specimens of D. ngoclinense do have a shallow transverse gular fold (particularly distinct on the paratype, VNMH 3110) ( Ananjeva et al., 2017: figs 2–4), identical to that seen in preserved specimens of D. splendidum [USNM 35522 (holotype), CIB 2588, 2591, 2596, 72468, 72469 from Chongqin, China]. Based on the available data, the only differentiating characteristic between D. ngoclinense from D. splendidum is the mid-dorsal scale count, which is higher in D. ngoclinense (54–56 vs. 44–52 in J. splendidum ; Ananjeva et al., 2017). However, such a difference is based on a small sample size of three specimens of D. ngoclinense , and mid-dorsal scale counts are known to vary in Diploderma ( Ota, 1989a; Manthey et al., 2012; Wang et al., 2016, 2018). In addition to the suspicious distribution of D. ngoclinense (isolated and 1000 km south of the most southern-known range of the genus; Ananjeva et al., 2017), we question the taxonomic validity of D. ngoclinense . Future field confirmation, detailed morphological comparisons and phylogenetic analyses are needed to validate the taxonomic status and distribution of this species.

Historically, almost all Diploderma diversity in central and south-west China was thought to be a single species, D. flaviceps ( Zhao et al., 1999) . Although numerous new species have been described from the D. flaviceps complex, including D. batangense , D. brevicaudum , D. flaviceps , D. iadinum , D. laeviventre , D. micangshanense , D. vela , D. yulongense and D. zhaoermii ( Song, 1987; Li et al., 2001; Gao & Hou, 2002; Manthey et al., 2012; Wang et al., 2015, 2016, 2017), many outlier records of D. flaviceps in south-west China have not been examined, some of which may represent either cryptic diversity in the genus or misidentifications ( Wang et al., 2016). For example, the genetic sequence data of an MVZ specimen from Wenchuan, north-west Sichuan Province, China ( MVZ 216622) was recorded as D. flaviceps upon deposition in GenBank, and subsequently has been used for numerous phylogenetic studies (GenBank accession no. AF128500 ; Macey et al., 2000; Schulte et al., 2004; Zug et al., 2006; Pyron et al., 2013; Grismer et al., 2016b). However, according to the museum record, the collection locality of this specimen is east of Wenchuan, Sichuan Province, China, which is geographically proximate to the type locality of a different congener, D. zhaoermii ( Gao & Hou, 2002) . Furthermore, our phylogenetic analyses recover this individual of D. cf. flaviceps as nested within topotypic material of D. zhaoermii ( Fig. 2). Additionally, as D. flaviceps is not recognized to occur outside the upper Dadu River Valley and its direct tributaries ( Manthey et al., 2012; Wang et al., 2016), we suspect that the Diploderma specimen ( MVZ 216622, genetic sequence on GenBank AF128500 ) was misidentified, and it represents the species D. zhaoermii instead. Poorly studied groups and continuous taxonomic revisions create problems such as this for museum and online databases, and numerous changes to the taxonomy of the D. flaviceps complex in China are no exception. We propose major natural history collections update the taxonomy of Japalura s.l., particularly members of the D. flaviceps complex from south-west China.