Tylototriton wenxianensis Fei, Ye and Yang, 1984
This species is listed as Vulnerable by IUCN (2010). The major threat is habitat loss and degradation due to development of montane green tea gardens, which are converted from old growth forest (Li et al., 2008). The range of tea gardens is increasing by 3% per year. To make green tea, firewood is collected in large quantities, which leads to damage of forest structure and drought. Some breeding ponds have dried out. Population fragmentation is another threat, making Tylototriton wenxianensis more vulnerable to human activities. The estimated population density is around 16 newts per square kilometer; total population size is around 30,000. Conservation measures were suggested in Li et al. (2008).
Medium-sized black Tylototriton, dorsolateral warts are connected into dorsolateral ridges. Boundaries between those warts are indistinct. Ventral warts are as big as dorsal ones. Cloacal region black in most specimens (Fei et al., 2006).
Karyotype:
2n=24, 1M, 2M, 3M, 4M, 5M, 6SM, 7M, 8SM, 9M, 10M, 11M, 12ST, from Gu and Tian (2000). M: metacentric; SM: submetacentric; T: telocentric; ST: subtelocentric
The mitochondrial genome has been sequenced by Zhang et al. (2008).
This species resembles Tylototriton asperrimus but differs from the latter species by an indistinct boundary between dorsolateral warts (forming dorsolateral ridges) and a black cloaca.
Medium-sized Tylototriton. Head flat and oval, with prominent bony ridges. Head width equals to head length. Rounded snout. No labial fold. Gular fold conspicuous. When forelimb is stretched forward, digits reach nostril. When limbs are adpressed, digits meet or slightly overlap. Bony ridge conspicuous on head. Dorsal ridge distinct. Dorsolateral warts connect into dorsolateral ridge; boundary between individual warts indistinct. Skin rough, size of warts nearly uniform on dorsum and venter. Tail compressed laterally and ending in a pointed tip. Tail shorter than snout-vent length. Dorsal color black; ventral color brownish black. Orange red only at digit tips and underside of tail. Cloaca region is black in most specimens; only a few have yellow cloacal lips (Fei et al., 2006). Some specimens have an orange tint on vertebral ridge and bony ridge on the head (Gong et al., 2008).
All measurements are from Fei et al. (1984).
Male (7 specimens). Snout-vent length: 70.2–73.6 mm; tail length: 55.1–67.4 mm; head length: 15.2–16.8 mm; head width: 15.1–16.9 mm; forelimb length: 21–22.6 mm; hind-limb length: 21.3–22.8 mm.
Tylototriton wenxianensis was first described as a subspecies of T. asperrimus (Fei et al., 1984). Fei et al. (1990) stated that the two species can be distinguished by the morphology of dorsolateral warts (separated vs. connected) and elevated T. wenxianensis to full species rank. Molecular phylogeny found that the two species are sister species and that genetic divergence is moderate (Zhang et al., 2008; Stuart et al., 2010). Recently, a subspecies of T. wenxianensis was described from Mount Dabie, T. wenxianensis dabienicus (Chen et al., 2010). This subspecies has a distinct long head (head length much larger than head width) which is in contrast with that of all Chinese species in the asperrimus species group (but is more similar to species from Southeast Asia).
The species has a disjunct distribution. It is found in Wenxian in southern Gansu, Pingwu and Qingchuan in northern Sichuan, Leishan in eastern Guizhou, Zhongxian, Yunyang, Fengjie counties of Chongqing, Mount Dabie of Henan, Shangzhi and Liuyang of Hunan and Yuexi in Anhui, from 650 to 2,500 m altitude (Fei et al., 2006; IUCN, 2010).
This species hides under big rocks near small ponds in well-preserved forest. Pond substrate is silt. Water is less than 1 m deep. Dense grasses grow around the pond (Li et al., 2008).
Breeding season appears to be from May to June. There is a report of courtship behavior observed in the wild (Gong et al., 2008), but it is unclear what observation methods have been used. Some parts appear to have been copied uncritically from existing literature, especially that on Echinotriton chinhaiensis, raising doubts about the value of the report.