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Photograph of dorsal head of specimens of Tylototriton verrucosus verrucosus from Myanmar (A: CAS 230940 [male]; B: CAS 230933 [female]), male topotype of T. v. verrucosus (C), and male holotype of T. uyenoi (D). Scale bar = 10 mm.
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We describe a new species of Tylototriton from Taunggyi, Shan State, central Myanmar, based on molecular and morphological evidence. The new species, Tylototriton shanorum, is classified as a member of the subgenus Tylototriton. The species differs morphologically from all known congeners by having the combination of dull-colored markings, weakly p...
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... the latter. The snout was truncate in the Myanmar species and T. v. verrucosus, but tended to be more rounded in T. uyenoi. Bony ridges on the head were less steep and narrow in the Myanmar species than T. v. verrucosus and T. uyenoi. The surface of the bony ridges tended to be rougher in the Myanmar species than in T. v. verrucosus and T. uyenoi (Fig. 4). The Myanmar species, together with T. uyenoi, had less prominent rib nodules and less segmented vertebral ridge than T. v. verrucosus (Fig. ...
Citations
... Many new species of crocodile newts have been described recently, based on a combination of morphological and molecular investigations (e.g. Nishikawa et al. (2013Nishikawa et al. ( , 2014; Le et al. (2015); Phimmachak et al. (2015); Khatiwada et al. (2015); Grismer et al. (2018Grismer et al. ( , 2019; Zaw et al. (2019); Bernardes et al. (2020); Li et al. (2020); Pomchote et al. (2020aPomchote et al. ( , 2021; Poyarkov et al. (2021b); Dufresnes and Hernandez (2022); Phung et al. (2023)). ...
An integrative taxonomic analysis combining molecular and morphological lines of evidence revealed a new cryptic species in the Tylototriton verrucosus species group from Manipur, northeastern India. The new species was previously confused with T. hima-layanus and T. verrucosus. Tylototriton zaimeng sp. nov. can be distinguished from its congeners by medium body size, head massive and wide with rounded snout and very wide and protruding supratemporal bony ridges and a well-developed sagittal ridge, short limbs not overlapping when adpressed along body, wide and not segmented vertebral ridge distinct, 13-14 pairs of rib nodules, brown colouration with dull orange to yellowish-brown markings on head, vertebral ridge, rib nodules, palms, soles, vent and ventral tail ridge and by vomerine teeth organised in two distinctly curved bell-shaped series. Phylogenetic analysis of the ND2 and 16S rRNA mtDNA genes confirmed the placement of the new species to the Clade I of the subgenus Tylototriton and suggested it is a sister species of T. panwaensis and T. houi (p-distance 3.0% in ND2 gene). The range of the new species is restricted to the Khongtheng Mountain Range and is isolated from the range of T. panwaensis and T. houi in northern Myanmar and southern China, respectively. We suggest the new species to be considered as Vulnerable (VU) in the IUCN Red List.
... Nonetheless, several key specimens included in phylogenetic studies of Tylototriton and Echinotriton originated from street markets in Asia, collected by locals to be eventually used for medicine or as animal curiosities (Fei et al., 2012;Hou et al., 2012;Nishikawa et al., 2014). Within our extensive dataset, we listed 26 such specimens, representative of no less than eight species, mostly of Chinese origin (T. ...
Crocodile newts (genera Echinotriton and Tylototriton) symbolize the outstanding biodiversity of Southeast Asia. In this study, we provide an exhaustive account of their evolution and diversity with an extensive phylogeography based on unprecedented mitochondrial (16.2kb) and nuclear sequence (3.2kb) alignments, combining barcoding information from nearly 1200 specimens collected over ~180 localities representative of all lineages known to date. While nuclear data lacked resolution, the mitochondrial tree of life highlighted an extreme dynamic of allopatric speciation that intimately followed climate cooling within the last 10 million years, a pattern shared with many other tropical and subtropical amphibians. In Crocodile newts, this dynamic implies weak dispersal and local adaptation as contributing factors of isolation, and was accompanied by macro- and micro-evolutionary changes in reproductive behaviors. Specifically, our resolved phylogeny of Tylototriton allowed tracing a major shift from conserved habits of terrestrial clutch spawning towards more plastic strategies involving both aquatic and land spawning of single eggs. Exploiting our framework, we then completed the taxonomy of crocodile newts by describing a new subgenus and two new species. Our study provides a checkpoint to guide future phylogeographic, speciation and conservation research in these iconic amphibians, which would greatly benefit from genomic resources.
... For morphological comparisons, the data for the other related species were taken from the related literatures (Fang and Chang 1932;Liu 1950;Nussbaum et al. 1995;Böhme et al. 2005;Hou et al. 2012;Nishikawa et al. 2013aNishikawa et al. , 2014Khatiwada et al. 2015;Le et al. 2015;Phimmachak et al. 2015;Grismer et al. 2018Grismer et al. , 2019Zaw et al. 2019;Pomchote et al. 2020aPomchote et al. , 2020b. ...
... The relationships of all morphometric characters were examined using principal component analysis (PCA). Note that the vent length of the one T. uyenoi female (THNHM 13869) was excluded from the morphological comparison because this parameter is much longer in males than in females [RVL 7.4 vs 1.7 and 1.9; 9.3 vs 4.0 in T. uyenoi, data from Nishikawa et al. (2014) and the present study, respectively]. All statistical analyses were performed using the SPSS v. 22 for Windows. ...
We describe a new species of the newt genus Tylototriton from Umphang Wildlife Sanctuary, Tak Province , western Thailand based on molecular and morphological evidence and named here as Tylototriton umphangensis sp. nov. The new species is assigned to the subgenus Tylototriton and differs from other species in having dark-brown to blackish-brown body and limbs, truncate snout, prominent antero-medial ends of the expansion of the dentary bones, laterally protruding quadrate regions, indistinct and small rib nodules, a well-segmented vertebral ridge, and rough dorsolateral bony ridges, which are steeper anterior, and curved medially at the posterior ends. The molecular data show that Tylototriton umphangensis sp. nov. differs from T. uyenoi sensu stricto by a 5% genetic sequence divergence of the mitochondrial NADH dehydrogenase subunit 2 region gene. The new species and T. uyenoi are both endemic to Thailand, distributed along the Northwest Thai (Dawna) Uplands of Indochina. To clarify the species boundary between Tylototriton umphangensis sp. nov. and T. uyenoi, additional field research is needed in adjacent areas. Tylototriton umphangensis sp. nov. is restricted to evergreen hill forests in Umphang Wildlife Sanctuary. We suggest that the new species should be classified as Endangered (EN) in the IUCN Red List.
... However, to understand evolutionary processes future studies especially on the ecology of the enigmatic crocodile newts are needed. Numerous species were just recently identified based on molecular data leading to an enormous increase in species numbers over the last decade (Stuart et al., 2010, Shen et al., 2012, Nishikawa et al., 2013a, Nishikawa et al., 2013b, Hou et al., 2014, Nishikawa et al., 2014, Khatiwada et al., 2015, Le et al., 2015, Phimmachak et al., 2015a, Qian et al., 2017, Grismer et al., 2018, Grismer et al., 2019, Zaw et al., 2019, Bernardes et al., 2020, Pomchote et al., 2020, Poyarkov et al., 2021. However morphological distinct characters are hard to identify and often appear somehow descriptive summarising differences of particular body part proportions based on a few specimens without any accounting for SD. ...
Sexual dimorphism (SD) is a main source of intraspecific morphological variation, however sexual shape dimorphism (SShD) was long time neglected in evolutionary research. Especially in cold-blooded animal groups only subtle shape differences are expressed between males and females and the selective forces behind it are poorly understood. Crocodile newts of the genera Echinotriton and Tylototriton are highly polymorphic in their reproductive ecology and hence, are a highly suitable model system to investigate potential evolutionary forces leading to SShD differences. We applied 3D geometric morphometrics to the cranial and humerus morphology of nine species of crocodile newts to investigate patterns of SShD in relation to the different mating modes. Trajectories of shape differences between males and females differ in both, cranium and humerus but mating mode does explain differences in SShD trajectories between species only in cranial morphology. Nevertheless, cranial morphology shape differed between the amplecting and circle dancing species. Hence, other selective forces must act here. Variable interspecific allometric trajectories are a potential source of shape differences whereas these trajectories are quite stable for the sexes irrespective of the species.
... Inle Lake has a unique geological history and rich biodiversity (Abell et al. 2008;UNDP 2015;Kano et al. 2016), and several new species have been described in the surrounding areas, even in recent years (e.g., Roberts 2007;Nishikawa et al. 2014). In the last few decades, populations of native fishes in Inle Lake have decreased due to environmental deterioration caused by water pollution and the introduction of exotic species (Toke et al. 2013;Kano et al. 2016). ...
... Tylototriton shanorum Nishikawa, Matsui and Rao, 2014 is a newt endemic to the Shan State, central Myanmar. The species was only known from Taunggyi and Nyaungshwe townships when it was described (Nishikawa et al., 2014). ...
... Tylototriton shanorum Nishikawa, Matsui and Rao, 2014 is a newt endemic to the Shan State, central Myanmar. The species was only known from Taunggyi and Nyaungshwe townships when it was described (Nishikawa et al., 2014). However, Pe (2018) later found the species in Kalaw (Baw Hseng in He Hoe, La-mine Village and Thar-mine-khem Dam in Aungpan) and Pindaya (Taung Paw Gyi Village and Lindley Inn Village) townships located north of Inle Lake (Fig. 1). ...
... Principal component analysis (PCA) was used to examine the relationships among specimens by all the morphometric characters. The vent length of the two DPKNP females were excluded from the morphological comparison because this parameter showed that males were much longer than females [e.g., male vs. female(s): 9.3 vs. 3.4 and 3.5 in T. shanorum; 7.0 vs. 2.9 in T. verrucosus verrucosus; 7.4 vs. 1.7 and 1.9 in T. uyenoi, data from Nishikawa et al. (2014); 10.5 vs. 4.0 and 3.4 in the DPKNP population from this study). All statistical analyses were performed using SPSS version 22 for Windows. ...
A new species of the genus Tylototriton, obtained from Doi Phu Kha National Park, Nan Province, northern Thailand, is described based on molecular and morphological evidence and named herein as Tylototriton phukhaensis sp. nov. The new species is morphologically distinct from the four known Thai Tylototriton species (T. panhai, T. uyenoi, T. anguliceps and T. verrucosus), in having a prominent, narrow, and straight sagittal ridge on the head that distinguishes it from the other Thai species. The molecular analysis also indicated that the new species is a distinct lineage and sister to T. anguliceps and T. uyenoi. The knowledge obtained in this study will greatly contribute to conducting the future conservation of Thai Tylototriton.
... Given the high demand of Tylototriton species in the international trade, and the persistent evidence of a high poaching rate (Gong and Mu 2008;Nishikawa et al. 2014;Phimmachak et al. 2015b;Rowley et al. 2016;Bernardes et al. 2017;Grismer et al. 2018) we decided to follow Hou et al. (2014) and cautiously omit the exact locations in this manuscript. ...
The Tylototriton asperrimus complex from northern Vietnam is reviewed based on morphological comparisons and analysis of the mitochondrial marker NADH dehydrogenase subunit 2 (ND2). Based on molecular divergences, which were revealed to be higher than in other congeners, in concert with morphological differences, two new species and one subspecies are described herein: Tylototriton pasmansisp. nov. differs from T. asperrimussensu stricto by 3.2 to 3.6 % genetic divergence and a combination of distinct morphological characters, such as head slightly longer than wide, distinct mid-dorsal ridge, relatively wide distance between the eyes, tips of fingers reaching the eye when foreleg is laid forward, labial and gular folds present, central belly skin with tubercles shaped like transverse wrinkles and distinct, pointy to round rib nodules. The population of T. pasmansisp. nov. consists of two subclades, the nominotypic one occurring on the eastern side of the Da River (or Black River, including Hoa Binh and Phu Tho provinces), and another occurring on the western side (including Son La and Thanh Hoa provinces). These two subclades differ by 2.5 to 3.1 % genetic divergence and distinct morphological characters. The western subclade is herein described as Tylototriton pasmansi obstissp. nov. , which differs from the nominotypic form by a wider head, longer and narrower snout, shorter femur length, and an overall less granulose skin, without an increased concentration of warts on the body sides.
A second new species, Tylototriton sparreboomisp. nov. is described from Lai Chau Province. It differs from T. asperrimussensu stricto by 4.1 to 4.2 % and from Tylototriton pasmansisp. nov. by 3.6 to 4.5 % genetic divergences as well as by a combination of distinct morphological characters, such as head longer than wide, tips of fingers reaching nostril when foreleg adpressed along head, rib nodules distinct, round and relatively enlarged, and wide distance between the eyes.
... It is also near the type locality for the bent-toed gecko Cyrtodactylus aequalis Bauer (Bauer 2003) and is the same type locality of a new species of Hemiphyllodactylus gecko (Grismer et al. in prep). Around Myanmar, many new amphibian species have also been discovered in recent years (Kӧhler et al. 2019;Poyarkov et al. 2019;Zaw et al. 2019) and a number of these have been around the Shan Plateau (Grismer et al. 2018d(Grismer et al. , 2019bNishikawa et al. 2014). Based on what is known about the natural history of Ansonia in general, they are often found close to streams which they use for breeding (Chan et al. 2014;Davis et al. 2016;Inger 1960;Inger et al. 2017;Quah et al. 2011;Waser et al. 2017;Wilkinson et al. 2012). ...
A new species of Ansonia is described from the Shan Plateau of Myanmar based on an integrative taxonomic analysis that differentiates it from all other congeners. Molecular phylogenetic analyses based on the mitochondrial genes 12S and 16S rRNA and tRNA-val recover A. kyaiktiyoensis sp. nov. as the sister species to A. inthanon from Thailand but differs from it and other congeners by at least a 5.0% sequence divergence. It is further differentiated by the following combination of morphological characters: (1) maximum SVL 24 mm in males and females; (2) first finger shorter than second; (3) absence of interorbital and tarsal ridges; (4) presence of light-coloured interscapular spot; (5) presence of yellow rictal tubercle; (6) absence of wide, light-coloured patch below eye; (7) presence of large, discrete, bright-yellow submandibular spots along the underside of lower jaw; (8) iris yellow-gold; (9) presence of markings on the snout consisting of streaks below the eye to the lip, and on the canthus rostralis to the nostril; (10) dorsum grey-brown with orange-beige spots, a dark-brown X-shaped marking on the back surrounding the interscapular spot, and dark-coloured markings on rump; (11) fore- and hind limbs with orange-beige cross-bars; and (12) venter light-gray with yellow spotting, especially near flanks and underside of hind limbs. Ansonia kyaiktiyoensis sp. nov. is the westernmost known record for the genus and the only species west of the Salween Basin. Its discovery echoes the increasing number of herpetological discoveries being made in upland regions fringing the Ayeyarwady and Salween Basins.
... Like the Salween Basin (see Grismer et al. 2018a,e), the Shan Plateau is rapidly emerging as a herpetologically diverse hot-spot in Myanmar, owing largely to its vast amount of karstic landscapes. More recently, its riparian areas are now proving to be sources of herpetological diversity as borne out by the newly described species of newts, Tylototriton shanorum Nishikawa, Matsui, & Rao, T. ngarsuensis Grismer, Wood, Quah, Thura, Espinoza, Grismer, Murdoch & Lin from Shan State (Grismer et al. 2018f;Nishikawa et al. 2014) and T. panwaensis Grismer, Wood, Quah, Thura, Espinoza, & Murdoch. Additionally, we are currently describing a new species of Stream Toad (Ansonia) from the extreme southwestern section of the plateau (Quah et al. submitted). ...
An integrative taxonomic analysis of the Cyrtodactylus linnwayensis group of the Shan Plateau recovered two new populations from isolated karst habitats near Pinlaung Town, Shan State as a new species, C. pinlaungensis sp. nov. Cyrtodactylus pinlaungensis sp. nov. is most closely related to a clade comprising C. linnwayensis and C. ywanganensis from the western edge of the Shan Plateau approximately 90 km to the northwest. Cyrtodactylus pinlaungensis sp. nov. can be distinguished from all members of the C. linnwayensis group by a number of statistically different morphological characters, discrete color pattern differences, and its heavy tuberculation. It also bears an uncorrected pairwise sequence divergence of 5.0–7.6% from all other species combined based on the mitochondrial gene ND2 and its flanking tRNAs. The discovery of this new species on the Shan Plateau continues to underscore the fact that this region is rapidly emerging as a herpetological diversity hot-spot for Myanmar.
