Three recent papers, three (or four) new Tylototriton species

[FrogEyes]

This paper further confirms the validity of Tylototriton shanjing as a species, and comments on additional diversity within the T.verrucosus group.


Mingwang ZHANG , Guohua YU , Dingqi RAO , Yimei HUANG , Junxing YANG, &Yan LI, 2013 (“2012”). A species boundary within the Tylototriton verrucosus group (Urodela: Salamandroidae) based on mitochondrial DNA sequence evidence. Journal of Animal and Veterinary Advances 12(3): 337-343.

Abstract:The taxonomic status of red knobby newt (Tylototriton shanjing) is under dispute. Molecular phylogenetic tree of Tylototriton verrucosus group was reconstructed based on 753 bp of partial mitochondrial cyt b gene sequence to determine species boundaries among the species in T. verrucosus group. The phylogeny result indicates that four major clades (clade I-IV) can be distinguished within Tylototriton verrucosus group. Clade I and IV consist of T. taliangensis and T. kweichowensis, respectively. Clade II consists of samples of T. shanjing derived from Yunnan of China, a form that researchers resurrect from its synonym under T. verrucosus. T. verrucosus haplotypes from Shan State of Myanmar and pet trade formed clade III. All populations of T. shanjing and T. verrucosus formed strongly supported (PP = 1.0) reciprocal monophyletic groups. The average uncorrected pairwise genetic distance (p-distance) of cyt b between these four clades ranges from 0.060-0.089 which is obviously higher than within these four major clades (0.001-0.014). Researchers propose that the T. shanjing should be a valid species rather than synonym of T. verrucosus.



This paper also confirms validity of T.shanjing, while also describing a closely related brown species from western Yunnan as T.daweishanensis.


ZHAO Tao-yan, RAO Ding-qi，LIU Ning，LI Biao，& YUAN Si-qi , 2012. Molecular phylogeny analysis of Tylototriton verrucosus group and description of new species. Journal of West China Forestry Science 41(5): 85-89


Abstract: Bayesian inference method is used to reconstruct molecular phylogenetic tree of the mitochondrial DNA ND2 gene of thirteen individuals of Tylototriton verrucosus group． The results show that: ( 1) Tylototriton verrucosus group is monophyletic． ( 2) T. shanjing is not a synonym of T. verrucosus but supported as a valid species． ( 3) Two specimens collected from Dawei Mount，Pingbian County，Yunnan Province are more closely related to T. shanjing． Above two species form a sister group and their interspecific genetic distance has reached a species level. Therefore，the species of the geographic population is recognized as a new species，named as Tylototriton daweishanensis sp. nov． The identification characters are: its forelimbs are longer than the hind limbs，brown black head，forearms and postbrachiums，orange temporal，fingers and toes．


I have commented a few times regarding the status of Tylototriton in Thailand, mentioning that “T.verrucosus” in that country are actually T.shanjing and an undescribed similar species. This most recent paper identifies three species in Thailand. One appears to be T.shanjing, but likely is not and awaits further study. Those from Doi Inthanon are closely related to T.shanjing and T.verrucosus and are described as Tylototriton (Tylototriton) uyenoi. Those from Loei are not subgenus Tylototriton, but rather Yaotriton. The latter are described as Tylototriton (Yaotriton) panhai. The paper further identifies T.pulcherimma as sister to three forms of “T.shanjing”, and these in turn to T.yangi, and then more distant cousins to Thai “T.shanjing” and T.uyenoi. Two species identified as T.verrucosus are related to this diverse group. Liangshantriton and Tylototriton (Qiantriton) are rejected by the authors, although their data do not actually refute Fei et al's revisions.


Kanto NISHIKAWA, Wichase KHONSUE, Porrawee POMCHOTE & Masafumi MATSUI, 2013. Two new species of Tylototriton from Thailand (Amphibia: Urodela: Salamandridae). Zootaxa 3737 (3): 261–279.

Abstract: Three morphological groups are found in a salamandrid newt Tylototriton shanjing from Thailand. We describe two of them as new species, one from northern and the other from northeastern Thailand, based on molecular and morphological data, however we could not make a taxonomic decision on the remaining one group because of the lack of voucher specimens and sufficient genetic data. The northern species differs morphologically from all known congeners by having the combination of orange to reddish brown markings, narrow and sharply protruding dorsolateral bony ridges on head, weakly segmented vertebral ridge, and long and high tail. The northeastern species is characterized by having the combination of yellow, orange, or reddish brown markings, wide and moderately protruding dorsolateral bony ridges on head, smooth vertebral ridge, black limbs, and black tail except for edges. Validity of taxonomic subdivision of the genus Tylototriton is discussed.


The first paper can be found online. The second must be ordered. The third also must be ordered, but can probably be found online within a few weeks. Many thanks to Kanto Nishikawa for his assistance.

Species list:
Tylototriton (Tylototriton) kweichowensis [aka Tylototriton (Qiantriton)]
Tylototriton (Tylototriton) shanjing
Tylototriton (Tylototriton) taliangensis [aka Liangshantriton]
Tylototriton (Tylototriton) uyenoi
Tylototriton (Tylototriton) verrucosus
Tylototriton (Tylototriton) yangi
Tylototriton (Yaotriton) asperrimus
Tylototriton (Yaotriton) broadoridgus
Tylototriton (Yaotriton) dabienicus
Tylototriton (Yaotriton) hainanensis
Tylototriton (Yaotriton) lizhenchangi
Tylototriton (Yaotriton) notialis
Tylototriton (Yaotriton) panhai
Tylototriton (Yaotriton) vietnamensis
Tylototriton (Yaotriton) wenxianensis
Tylototriton (Yaotriton) ziegleri

There remain several undescribed species in subgenus Tylototriton, probably in subgenus Yaotriton, and in genus Echinotriton.

 

[FrogEyes]

Edit - closer scrutiny of the last paper shows that they formally treat three lineages of T.shanjing and T.pulcherimma as a single species, with the latter being the closest relative of typical T.shanjing. Some other lineages of T. "shanjing" are candidate species. With the synonymization of T.pulcherimma, T.yangi and T.shanjing are sister species, sister in turn to T.uyenoi and an undescribed Thai "T.shanjing" candidate species.

They also indicate that they suspect T.broadoridgus to be conspecific with T.dabienicus [by implication, these would be synonyms of T.wenxianensis]. They do not formally make such a change however.