Tylototriton hainanensis Fei, Ye and Yang, 1984
This species' range is limited to Hainan Island. Although it mostly occurs in national nature reserves, this species is threatened by habitat loss and degradation due to agriculture, clear-cutting and infrastructure development for tourist activities (IUCN, 2010). Tylototriton hainanensis is listed as Endangered. In Jianfengling National Nature Reserve, population density is around 30 individuals per square kilometer (Wang et al., 2008).
Skull much wider than length (width/length > 1.2), whereas skulls of the similar looking T. asperrimus and T. wenxianensis are roughly equal in width and length (width/length ca. 1). Boundary between dorsolateral warts is clear. When a forelimb is stretched forward, finger tips only reach the eye (whereas they reach the nostril in T. asperrimus and T. wenxianensis). Dorsal color dark brown; some individuals have orange-tinted dorsolateral warts.
Mitochondrial and nuclear sequence data are available from Weisrock et al. (2006) and Stuart et al. (2010).
Medium-sized Tylototriton. Slightly larger than T. asperrimus and T. wenxianensis. Head flat and wider than long, with weakly developed bony ridges. Rounded snout. Gular fold present. Body slender and flattened. Dorsal ridge distinct but low and segmented; 14–16 large dorsolateral warts prominent with clear boundary. Skin rough, with fine granules. Small transverse wrinkles on venter. Tail compressed laterally and ending in a rounded tip. Tail shorter than snout-vent. Dorsal color dark brown; ventral color greenish grey. Tips of digits, surroundings of cloaca and lower margin of tail orange-red. Some individuals have orange-tinted dorsolateral warts (Fei et al., 1984; Fei et al., 2006).
All measurements are from Fei et al. (1984).
Male (4 specimens). Total length: 137.4–148 mm; snout-vent length: 73.2–77 mm; head length: 16.2–17.3 mm; head width: 19–19.5 mm; forelimb length: 19.1–21.6 mm; hind-limb length: 20–22 mm.
Female (7 specimens). Total length: 125–139.6 mm; snout-vent length: 73.5–77.7 mm; head length: 15.3–17.2 mm; head width: 18.5–20 mm; forelimb length: 20.7–23.1 mm; hind-limb length: 20.2–23.2 mm.
In external characters Tylototriton hainanensis is similar to T. asperrimus; it was considered a population of the latter species when first discovered (Liu et al., 1973). Molecular phylogeny derived from mitochondrial DNA sequence data recognized T. hainanensis as the likely sister species to another newly described species, T. notialis (Stuart et al., 2010).
The species is known from Mount Wuzhi, Mount Diaoluo and Jianfengling in Hainan, China, from altitudes between 770 and 950 m (IUCN, 2010).
Tylototriton hainanensis lives under dead leaves or root holes in heavily shaded forest in the mountains. During the breeding season, it is mostly found near ponds in broadleaf and bamboo forest (Fei et al., 1984).
Breeding season is likely around May because egg clutches were found in mid May. Eggs are laid in clutches on land under dead leaves. A clutch contains 58–90 eggs (Fei et al., 1984).