Cynops orientalis (David, 1873)
Chinese Fire-bellied Newt
The Chinese Fire-bellied Newt is the smallest species of the East Asian salamandrid genus Cynops. In its morphological features this species is distinctly different from other taxa in this genus. Head relatively large, a little longer than broad; snout rounded. Palatine teeth in two longitudinal series, commencing from front of choanae meeting anteriorly, gradually diverging posteriorly. Tongue small, practically free at the sides. Paratoids moderately developed, their posterior borders demarcating head from neck. Faint vertebral ridge. Tail rather short, approximately the length of the body. Margins of dorsal and ventral tail fins nearly parallel in breeding male, ending rather abruptly in a rounded, blunt tip. Skin rather smooth, especially in aquatic individuals (Chang, 1933). Lateral line organs clearly discernible in water.
Male smaller than female, especially the tail is shorter in the male than in the female. In the reproductive season, males have well developed dorsal and ventral tail fins, and a swollen cloaca.
Colour is dark-brown to black above, occasionally greyish. Colour of belly and throat lively red or orange with many rounded black spots. The base of each limb, anterior part of the cloaca and ventral tail fin are orange, posterior part of cloaca is black (Fei et al., 2006).
Total maximum length 7 to 9 cm.
Eggs are laid individually, under and between leaves, folded in a leaf, in floating roots and grasses. Size of oval-shaped jelly mass 4 to 2.5 mm, egg rounded, 2 mm in diameter. A female can lay a little over 100 eggs per season on average (Kung et al., 1960; Yang & Shen, 1993), from March to mid-June. Optimal water temperature for egg deposition is 15 to 23° C. Eggs laid in water of 18-25° hatch in 11 to 17 days, at lower temperatures hatching takes considerably longer (Kung et al., 1960; Yang & Shen, 1993).
One insemination is sufficient for a female to lay fertilized eggs during two months; in this and other features of oviposition and early development there are differences between C. orientalis and C. cyanurus (Yang & Shen, 1993).
Hatching larvae are 10-12 mm. Larvae are uniformly dark-brown to black, a little lighter on the ventral side, and take approximately 50 to 80 days to metamorphose. After metamorphosis at a length of 30-35 mm (Yang & Shen, 1993; Bogaerts, 1999), juveniles live on land.
C. orientalis is widely distributed at the lower reach of the Yangtze River and adjacent areas, in the hilly plains of central and southeastern China at 30 to 1,500 m altitude (the provinces of Henan, southern Hubei, southern Anhui, Jiangsu, Zhejiang, Guangxi, Fujian, and Hunan, Zhao & Hu, 1988; Fei et al., 2006).
The habitat is described as consisting of all suitable water bodies at various altitudes, mountain ponds, seepages and paddy fields in hilly areas, small brooks, flooded fields in mountain valleys, in forests and degraded areas. Locally it may be very abundant. “Always the water is cold and quiet, in the shade of grass, with a mud bottom free from stones” (Chang & Boring, 1936). For egg deposition C. orientalis often chooses lentic water bodies such as ponds, wells and farmland ditches (Yang & Shen, 1993).
There are no studies in western languages on natural history and ecology of this species. Although the newts are often aquatic, they also live on land outside the breeding season. In Zhejiang where winters are mild, C. orientalis does not hibernate and can be found all year round (Fei et al., 2006). According to observations by Yang & Shen in Hunan (1993), males enter the breeding pond first in January and February, resulting in an initial sex-ratio eschewed towards males. Fei et al. (2006) refer to a peak in the breeding season from late April to mid May. Males and females leave the breeding water from July to September.
Reproduction and courtship behaviour is similar to that of other Cynops species, but shows temporal differences. The male identifies a female by sniffing her body. He positions himself in front of her, and rapidly vibrates the distal part of his tail, fanning towards her snout. If the female is responsive, she stays still or moves towards the male. The male then turns round, creeping ahead of the female. He deposits a spermatophore on the substrate and the female picks it up with her cloaca. The male’s tail-fanning courtship display and creep movements ahead of the female are of relatively short duration and one spermatophore is deposited a few seconds after the male starts to creep ahead of the female. The female looses interest in the male soon after the first spermatophore deposition. The male may bite and hold on to the female for a short while afterwards (Sparreboom & Faria, 1997).
Threats and conservation
Given the local abundance of this species and its large distribution, the Chinese Fire-bellied Newt is not immediately endangered. Habitat destruction and degradation are major threats to this species, as well as the use of herbicides and insecticides on rice terraces (IUCN, 2009). The animals are sold by the thousands in pet-markets in China and Europe.
Observations in captivity
This species has been successfully kept and bred in captivity. It can be kept aquatic all year round. Most observations on its behaviour were made in aquariums (Koepernik & Herrmann, 1991; Bachhausen, 1998; Sparreboom, 1998; Bogaerts, 1999; Miller, 2005). It prefers dense vegetation and still water and takes all sorts of living and dead food items. In captivity juveniles can be persuaded to live in water, where they grow faster than on land (Bogaerts, 1999).
Given the broad distribution and common occurrence of this species, it is surprising that so little is known about its natural history.
Bachhausen, P., (1998). ‘Der Chinesische Zwergmolch – ein dankbarer Pflegling für vollaquatische Urodelenhaltung.’ elaphe, 6: 13-16.
Bogaerts, S., (1999). ‘Houden en kweken van de Chinese Vuurbuiksalamander, Cynops orientalis.’ Lacerta, 57: 151-160.
Chang, M.L.Y., 1933. ‘On the Salamanders of Chekiang.’ Contr. Biol. Lab. Sci. Soc. China, 9: 305-328.
Chang, T.K. & Boring, A.M., (1936). ‘Studies in Variation among the Chinese Amphibia I. Salamandridae.’ Peking Nat. Hist. Bull., 9: 327-361.
Fei, L., Hu, S., Ye, C. & Huang, Y., (2006). Fauna Sinica, Amphibia, Vol. I. Beijing, Science Press (in Chinese).
IUCN, (2009). IUCN Red List of Threatened Species. Version 2009.2. http://www.iucnredlist.org/ Downloaded on 9 February 2010.
Koepernik, U. & Herrmann, H.-J., (1991). ‘Haltung und Vermehrung von Cynops orientalis (David 1873).’ In: Amphibienforschung und Vivarium, pp. 55-56. Herrmann, H.-J., Ed., Naturhistorisches Museum Schloss Bertholdsburg, Schleusingen.
Kung, C.-C., Chang, C.-M. & Tsai, B., (1960). ‘Observations on the Early Development of Cynops orientalis (David).’ Acta zool. Sinica, 6: 175-184, 2 plates (in Chinese with English summary).
Miller, J.J., (2005). ‘Cynops (Tschudi, 1839) Fire Belly Newts.’ Living Underworld Species Database. Livingunderworld.org. http://www.livingunderworld.org/. Accessed May 2005.
Sparreboom, M., (1998). ‘Maintenance and Breeding of Newts of the Genus Cynops.’ British Herpetol. Soc. Bull., 63: 3-12.
Sparreboom, M. & Faria, M.M., (1997). ‘Sexual Behaviour of the Chinese Fire-bellied Newt, Cynops orientalis.’ Amphibia-Reptilia, 18: 27-38.
Wu, Y., Wang, Y., Jiang, K. & Hanken J., (2010). ‘A New Newt of the Genus Cynops (Caudata: Salamandridae) from Fujian Province, southeastern China.’ Zootaxa, 2346: 42-52.
Yang, D.-D. & Shen, Y.-H., (1993). ‘Study on the Reproductive Ecology of the Salamander (Cynops orientalis).’ Zoological Research, 14: 215-220 (in Chinese).
Zhao, E. & Hu, Q., (1988). ‘Studies on Chinese Tailed Amphibians.’ Pp. 1-48 in: Zhao, E., Hu, Q., Jiang, Y. & Yang, Y. Studies on Chinese Salamanders. Society for the Study of Amphibians and Reptiles.
Friday, June 10, 2011