The animal is rare. Habitat destruction and degradation form the main threats. It is considered vulnerable (Stuart et al., 2008; IUCN, 2010).
Vomerine teeth series relatively long with 12–17 teeth on each side. Lungs long, reaching the 8th or 9th costal groove posteriorly. No labial folds; no cornified coverings on palms and soles. 11–12 costal grooves. Distinct dorsal coloration: dark purple with irregular yellow blotches. During breeding season, males develop small white spines on head, dorsum and the dorsal side of limbs (Fei et al., 2006).
2n=52, 1M, 2M, 3SM, 4ST, 5ST, 6M, 7M, 8SM, 9M, 10T, 11M, 12M, 13M, m (14–26), from Ikebe et al. (2000).
M: metacentric; SM: submetacentric; T: telocentric; ST: subtelocentric; m: micro-chromosome
The mitochondrial genome has been sequenced by Peng et al. (2010).
This species resembles Pseudohynobius kuankuoshuiensis, P. guizhouensis and P. jinfo due to the presence of numerous dorsal yellow spots. But these spots are large and irregularly shaped in P. flavomaculatus; all other three species have small and oval-shaped spots (Wei et al., 2009; Li et al., 2010).
Head slightly flattened, slightly longer than width (length/width < 1.55, Xu et al., 2007). No labial fold. Long vomerine teeth rows with 12-17 teeth in each row. On the head, a thin groove runs from the back of the eye to the gular fold, and another groove runs dorsally from the back of the head to the tail base. Tail length similar to snout-vent length. 11 (few 12) costal grooves (Fei & Ye, 1982). When limbs are adpressed, fingers and toes slightly overlap. Four fingers, five toes. A noticeable but short tailfin fold is present. Skin smooth. The male has a longer and higher tail than the female. During the reproductive period, head, back and external surface of limbs in the male have tiny white spines (Fei & Ye, 1983a, 1983b; 2001; Kuzmin & Thiesmeier, 2001). Upper side purple-brown, marked unevenly with yellow or dark yellow, irregular blotches. The amount, size and shape of yellow blotches may vary individually. Generally, yellow markings are smaller on the head, larger on dorsal trunk, and tiny or no markings are present on the tail. Under side light purple.
All measurements are from Fei & Ye (1982).
Male (10 specimens). Snout-vent length: 80.4–92 mm; tail length: 77.6–97.3 mm; Head length: 18.2–22.2 mm; Head width: 13.9–16.3 mm; forelimb length: 22.3–22.4 mm; hind-limb length: 22.4–24.5 mm.
Female (10 specimens). Snout-vent length: 76.7–93.5 mm; tail length: 58.4–85.8 mm; Head length: 18.9–22.3 mm; Head width: 12.3–14.3 mm; forelimb length: 20.2–22.4 mm; hind-limb length: 23–27 mm.
This species was initially described as a new species in the genus Hynobius (Hu et al., 1978; Fei & Ye, 1982), but was later elevated to the new genus Pseudohynobius, containing P. flavomaculatus and P. tsinpaensis (Fei & Ye, 1983). However, Zhao & Wu (1995) considered P. flavomaculatus as a synonym of P. tsinpaensis and Pseudohynobius as a synonym of Ranodon. All those studies are based on morphology and osteology. Recently mitochondrial and allozyme data from Zeng et al. (2006) suggest the validity of Pseudohynobius and a sister-relationship between Pseudohynobius and Liua (Ranodon tsinpaensis was transferred to Liua). So P. flavomaculatus is the not a synonym of Liua tsinpaensis.
This species occurs in Lichuan County, Hubei Province and Sangzhi County, Hunan Province, China (Zeng et al., 2006). Populations from Nanchuan County, Chongqing and Suiyang County, Guizhou have been designated to two new species: Pseudohynobius jinfo and P. kuankuoshuiensis, respectively.
This species occurs in montane areas where bushes, bamboo forest and streams are abundant (elevation 1,100–1,845 m). The upper streams often become swamps. Near the source of the stream are many small springs. Adults are terrestrial, hiding under bamboo roots or mosses or in crevices or burrows during daytime. These salamanders are difficult to find. At night, they come out and prey on insects and millipedes or enter the stream to catch aquatic arthropods (Fei et al., 2006).
Breeding season is from mid April to May. Egg sacs were found in a small pool near a tiny spring (water temperature 8 °C), which came out from a small burrow (the opening only 5 cm wide). More egg sacs were found inside the burrow that expanded in diameter with clay ceiling and rocky floor. One end of the egg sac was attached to the ceiling. Adults were found near egg sacs. There were many branches inside the burrow. Thirty-six adults were dug out in an area of 6 square meters (Fei et al., 2006). The pair of egg sacs is coiled in a C-shape, the distal end tapering. The egg sacs are similar to those of Liua tsinpaensis. Length 130-270 mm. 16-26 eggs per egg sac (Kuzmin & Thiesmeier, 2001). Eggs are round, 5.5 mm in diameter, and pale or light gray in coloration. Larvae hatched in one month. They are light brown, with upper labial folds. Tailfin fold is wide, extending to the midpoint of the body (Fei & Ye, 2001; Kuzmin & Thiesmeier, 2001). Larvae feed on insects and small crustaceans, and take 1.5 to 2 years to metamorphose (AmphibiaWeb, 2010).