AmphibiaChina 中国两栖类.

Conservation Status (definitions)

IUCN Red List Status Account Critically Endangered (CR) - Provisional CITES Appendix I National Status None Regional Status None

Description
Andrias sligoi is one of the largest amphibians in the world. It has a squat, depressed body with thick cutaneous folds along both sides. There are a few small tubercles found on its body, but none on its head. It has a large, depressed head. It has a rounded snout with small, widely separated nostrils. It has small but prominent eyes. The distance between its eye and labial border is 3.5 times the distance between its nostrils. It has short and stout limbs with depressed fingers and toes. Its fingers, toes, and fibula are bordered by membranes. It has a short, compressed, and finned tail, the end of which is rounded (Boulenger 1924).

DIAGNOSIS:

This species was first described as Megalobatrachus sligoi by Boulenger (1924). The holotype specimen was found in the Hong Kong Botanical Gardens, but it was soon evident that it originated from the mainland and had been transported over. Boulenger suggested that this was a separate species because it differed significantly in morphology from other giant salamanders in China and Japan, which he grouped all under a single taxon, Megalobatachus muximus, and which he believed had no morphological distinctions. Those species are now known as Andrias davidanus and A. japonicus, respectively. However a third, unnamed Andrias has also been identified from Huangshan in the Anhui Province of China (Yan et al. 2018, Turvey et al. 2019). Boulenger (1924) suggested that A. sligoi differed from other Andrias species in that the former has a longer, flatter, and smoother head (vs. covered in tubercles), nostrils that were much more widely separated and had a larger distance between its eye and labial border - 3.5 times greater than the distance between its nostrils compared to a 1.5 times difference in other species (Boulenger 1924). However, these supposed morphological differences should be considered with caution, in light of Boulenger’s mistaken belief that all other giant salamanders could be grouped into a single species; the other specimens he examined probably did not represent the full phylogenetic and biogeographic spectrum that is now known to exist. Megalobatrachus sligoi eventually became synonymized with A. davidianus (Thorn 1968), a situation that was overturned in 2019 (Turvey et al. 2019).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: China

View distribution map in BerkeleyMapper.

Andrias sligoi was historically found in fast-flowing streams in parts of the Nanling mountains of China, which separate the Yangtze and Pearl River drainage basins, and in tributaries of the Pearl River drainage (Turvey et al. 2019). However, beginning in 1922, Andrias individuals were moved across China, and many individuals in the wild are likely hybrids now (Yan et al. 2018, Turvey et al. 2018, 2019).

Life History, Abundance, Activity, and Special Behaviors
It can be assumed that, along with other Andrias clades, A. silgoi is a top predator in the montane freshwater ecosystems it inhabits. It can also be assumed that it is long-living with delayed sexual maturity (Turvey et al. 2019). There is no available information as to how its life history traits and behavior differs from other Andrias clades.

Trends and Threats
Andrias sligoi has been exploited by humans for centuries, for local subsistence and traditional medicine. However, it was only from the 1950s, and especially the late 1970s on, when China began its transition to a capitalist market economy, that A. sligoi and other Andrias species began to come under serious threat. Southern Chinese people, who had traditionally consumed them, were allowed to translocate them around the country. This resulted in the salamanders becoming increasingly traded and transported across great distances to supply a ballooning domestic luxury food market. A salamander farming industry started developing in the early 2000s. This in turn led to further poaching, in addition to threats from genetically-mixed escapees and transplants, and the potential spread of disease from salamander farm effluent and transplanted salamanders. Further threats include chemical runoff from farms; hydroengineering schemes that have altered and drowned formerly suitable habitat; and climate change, which will have particularly strong impacts on their high-elevation habitats. An extensive, years-long survey of giant salamanders across China found that giant salamanders are extremely depleted or functionally extinct across their range. The few individuals detected in the Pearl River watershed had a Yellow River matriline, indicating that they were either farm releases or escapes (Turvey et al. 2018).

Relation to Humans
Andrias silgoi has been eaten and used for traditional medicine for centuries. The salamanders were historically sold to other cities from the trading center of Guangzhou, which is located in the Pearl River Delta. It is unclear how much they were exploited for local use rather than the market in the distant past. In more recent times, however, they have become increasingly exploited for sale on the luxury food market. This has, since the early 2000s, fed a giant salamander farming industry, which is without precedent in Chinese history (Turvey et al. 2019).

Possible reasons for amphibian decline

General habitat alteration and loss
Intensified agriculture or grazing
Habitat fragmentation
Local pesticides, fertilizers, and pollutants
Disease
Intentional mortality (over-harvesting, pet trade or collecting)
Climate change, increased UVB or increased sensitivity to it, etc.

Comments

PHYLOGENETIC RELATIONSHIPS:

Prior to 2018, it was believed that there were only two species of Andrias: A. davidianus, found in China, and A. japonicus, found in Japan (Turvey et al. 2019). However, using Bayesian Inference of partial cytb, COI, and D-loop mtDNA and nuclear SNPs of modern, wild-caught samples Yan et al. (2018) identified at least five cryptic species of giant salamanders throughout China. Turvey et al. (2019) followed up on this study with Bayesian analyses of mitogenomic sequences using Boulenger’s specimen as well as other Chinese giant salamander museum specimens and tissues collected before widespread transplanting occurred, in order to further clarify Andrias phylogenetic relationships and historical biogeography. They identified at least three separate Andrias lineages in China and determined that the holotype of M. sligoi, along with another specimen, represents a clade native to the Nanling Mountain/Pearl River Basin ecoregion. They resurrected the species epithet, sligoi, from Boulenger (1924) and suggested “South China giant salamander” as a common name.

Turvey et al. (2019) estimated the divergence of A. silgoi, the basal group, to date back to ~3.1 mya, while the other two clades diverged ~2.5 mya. Yan et al. (2018) and Turvey et al. (2019) both identified a unique clade from Huangshan in the Anhui Province, however neither study named the lineage.

The results from Turvey et al. (2019) indicate that speciation occurred as a result of mountain formation.

References

Boulenger, EG. (1924). “On a new giant salamander, living in the Society’s Gardens.” Proceedings of the Zoological Society of London, 1924, 173–174.

Thorn, Robert (1968). Les Salamandres d'Europe, d'Asie et d'Afrique du nord. Lechevalier, Paris.

Turvey, S.T., Chen, S., Tapley, B., Wei, G., Xie, F., Yan, F., Yang, J., Liang, Z., Tian, H., Wu, M., Okada, S., Wang, J., Lü, J., Zhou, F., Papworth, S.K., Redbond, J., Brown, T., Che, J., Cunningham, A.A. (2018). “Imminent extinction in the wild of the world’s largest amphibian.” Current Biology, 28(10), R581–R598. [link]

Turvey, S.T., Marr, M.M., Barnes, I., Brace, S., Tapley, B., Murphy, R.W., Zhao, E., Cunningham, A.A. (2019). “Historical museum collections clarify the evolutionary history of cryptic species radiation in the world’s largest amphibians.” Ecology and Evolution, 9(18), 10070-10084. [link]

Yan, F., Lü, J., Zhang, B., Yuan, Z., Zhao, H., Huang, S., Wei, G., Mi, X., Zou, D. Xu, W., Chen, S., Wang, J., Xie, F., Wu, M., Xiao, H., Liang, Z., Jin, J., Wu., S., Xu, C., Tapley, B., Turvey, S., Papenfuss, T.J., Cunningham, A.A., Murphy, R.W., Zhang, Y., Che, J. (2018). "The Chinese giant salamander exemplifies the hidden extinction of cryptic species." Current Biology, 28(10), R590–R592. [link]

Species Account Citation: AmphibiaWeb 2022 Andrias sligoi: South China Giant Salamander <https://amphibiaweb.org/species/9090> University of California, Berkeley, CA, USA. Accessed Nov 23, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 23 Nov 2024.

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