Listed on CITES Appendix I. Class II state major protected wildlife species in China. Critically endangered under IUCN (2010). The wild populations were harvested heavily in the 1980s for their meat, which is considered a valuable delicacy. Deforestation also destroyed natural habitat at the upper reaches of rivers. Population size in the wild shrinks tremendously. Although many natural reserves have been established to protect this species, wild animals are rarely seen now. On the other hand, salamander farms are increasing in numbers and succeed in artificial breeding. But the purpose of farming is to supply the market and not to restock wild populations.
Adult total length exceeds 100 cm. Head and body are flat. Tail is laterally compressed. Eyes are very small, on the dorsolateral side of the head. Eyelid is absent. Thick skin folds are present at the lateral side of the body. Tubercles are in pairs and arranged in rows.
2n=60, 1M, 2M, 3M, 4T, 5T, 6T, 7T, 8T, 9SM, 10T, 11SM, 12ST, 13T, 14T, 15T, 16T, 17M, m (18–30), from Moreacalchi et al. (1982)
2n=60, 1M, 2M, 3M, 4T, 5T, 6T, 7T, 8T, 9M, 10M, 11T, 12ST, 13T, 14T/ST, 15T, 16T, 17M, m (18–30), from Sessions et al. (1982).
M: metacentric; SM: submetacentric; T: telocentric; ST: subtelocentric
The mitochondrial genome has been sequenced by Zhang et al. (2003).
The Chinese giant salamander is morphologically similar to its sister species, the Japanese giant salamander. The Chinese species has paired tubercles on its head and throat, which are arranged in rows. The Japanese species has single and scattered tubercles.
A large, stout and flat salamander. Head is wide and flat, reaching 1/5–1/4 of the snout-vent length. Paired tubercles are arranged in rows on the head and neck. Snout is rounded with small nostrils near the snout tip. Eyes are small and without eyelid. Mouth is very big. Labial fold is prominent at the posterior of the upper jaw. Tongue adheres to the mouth floor with free lateral margins. Gular fold is present. Thick skin folds are present at the lateral side of the body. There are 12–15 costal grooves. All four limbs are short and stout with skin folds. The salamander has four fingers and five toes with not very prominent interdigital webbing. Tail length is between 59 and 80% of the snout-vent length (Liu, 1950). Dorsal fin of the tail is prominent, whereas ventral fin is only conspicuous near the vent. Females have smooth, non-swollen vent and males have tubercles around their swollen vent (Fei et al., 2006).
Coloration exhibits great variation. Most specimens are dark brown, but individuals can be black, dark red, light brown or earth-toned. There are large irregular dark flecks or blotches on the dorsal and ventral side. Juveniles often have lighter coloration with small black flecks. Albinos (white or golden) have been recorded (Fei et al., 2006).
Electrical stimulation of the midbrain evokes calls and secretion of skin glands, which produce milky white, foul-smelling mucus. Other responses include gaping, locomotion and tail lashing (Lan et al., 1990).
All measurements are from Fei et al. (2006).
Male (2 specimens). Total length: 760–900 mm; snout-vent length: 480–585 mm; Head length: 125–158 mm; Head width: 112–146 mm; forelimb length: 81–93 mm; hind-limb length: 100–125 mm; weight: 2600–4100 g.
Female (8 specimens). Total length: 470–875 mm; snout-vent length: 310–585 mm; Head length: 72–125 mm; Head width: 58–118 mm; forelimb length: 49–85 mm; hind-limb length: 62–113 mm; weight: 400–2800 g.
Cryptobranchid salamanders and the hynobiids form the sister clade (Cryptobranchoidea) to all other extant salamanders excluding the Sirenidae based on complete mitochondrial genome data (Zhang & Wake, 2009).
Murphy et al. (2000) sampled 19 Chinese giant salamanders across their distribution range and found moderate divergence among populations using isozyme electrophoresis and mitochondrial DNA sequences. They did not find phylogeographic patterns that correspond to the three Chinese major river systems.
Central China, the lower reaches of the Yangtze River, the Yellow River and the Pearl River.
Chinese giant salamanders live in cool (under 23 °C) and rapid streams at elevations of 100–1,200 m, but have been found at 4,200 m altitude in Qinghai. They prefer cavities along the riverbanks or under water. Adults live individually in deep water; larvae stay together in crevices at shallower depths. They are mostly nocturnal and feed on aquatic invertebrates (such as crawfish and crabs), fish and frogs (Fei et al., 2006).
Reproductive season is from May to September. Eggs are laid from July to September. After mating, the male cleans the nest in the underwater cavity and the female follows and lays the eggs, which are individually enclosed in the capsule. The egg sac is like a slender string. Egg diameter is 5–8 mm and capsule diameter is 15–17 mm. Clutch size depends on body weight. Females that weigh 0.5–3 kg can lay 300–600 eggs or more. The male guards the eggs until they hatch. Incubation takes 38–40 days under water temperatures of 14–21°C. Hatchlings are 25–31.5 mm in length. External gills disappear when total length reaches 170–220 mm (Fei et al., 2006).
The meat is considered a delicacy and is sold for high prices. It is used as a traditional Chinese medicine and supposedly helps to reduce anemia. The skin can be tanned to leather (Fei et al., 2006).