Metadata

Troglonectes jiarongensis

(Lin, Li and Song 2012) Huang, Yang, Wu and Zhao 2019

ORDERSUB-ORDERFAMILY
CypriniformesCobitoidei Nemacheilidae

Synonyms

Triplophysa jiarongensis   Lin, Li and Song 2012

Country

China

Types

Holotype: SOU 10111801 49.2mm SL, 57.9mm TL. Paratypes: SOU 10111802, 10111803.

Distribution

Type locality: Shuijingwan Cave, Jiarong Town, Libo County, Guizhou Province, China. 25°28'12.89”N, 108°06'34.35”E, altitude 634m. Also recorded from Menshui Cave, Limingguan Village, Banzhai Township, Maolan Town, Libo County, Guizhou Province (25o12'14.79"N, 108o01'21.58"E). These two locations are reported to be hydrologically linked (Liu et al 2019). Zhang et al (2000) reported that these caves were initiated c. 91000-163300 years ago.

Systematics

The original description placed this species in Triplophya and this is followed in the authoritative summary of world loaches by Kottelat (2012:127) and by Zhang and Zhao (2016:138). Xu, Deng and Zhou (2017) place it in Oreonectes but without explanation. In a fuller examination using both morphological and molecular approaches Liu et al. (2019) showed conclusively that the species belongs in the genus Oreonectes. Liu et al. (2019) showed that O. jiarongensis is in a monophyletic group with O. daqikongenis, O. shuilongensis and another species they call O. furcocaudalis. However the last species was transfered to the genus Troglonectes by Zhang and Zhou (2016). This work suggests that Troglonectes and Oreonectes are sister genera but this will require confirmation from further molecular studies.

There are 19 described species in the genus Troglonectes (Eschmeyer 2022), all expect one are hypogean fishes with reduced eyes, reduced pigment and reduced scales. The only epigean member of the genus is Troglonectes hechiensis Zhao, Liu, Du and Luo 2021. The epigean species is a member of a monophyletic group which also contains T. furcocaudalis, T. daqikongensis, T. jiarongensis and T. shuilongensis (Zhao, Liu, Du and Luo 2021).

Biological Notes

Xu et al. (2017) examined the response of the species to light and showed that it took only 14 days to generate dark melanin-pigmented regions on the body. Their explantion for this response was that the caves they are found in are relatively young (see Systematics, above) and therefore that this species developed its troglomorphy only recently and has not yet received mutations in the melanin-sythesis path that are found in other, longer-evolved, species such as Astyanax jordani. Clearly this is an early observation and more work is required to substantiate this reasoning.

Conservation Status

MuG [NE]

Museum Holdings

As above plus: GZNU20090820001, GZNU 20090820010, GZNU 20160803001, GZNU 20160803015.

Internet Resources

Oreonectes jiarongensis cytochrome b (cytb) gene, mitochondrial

Key References

Zhang, M., Liu, Y. and Ran, J. Journal Article 2000 The characteristics of karst caves development in Libo, Guizhou
Kottelat, M. Journal Article 2012 Conspectus cobitidum: An inventory of the loaches of the world (Teleostei: Cypriniformes: Cobitoidei)
Lin, Y., Li, C. and Song, J.K Journal Article 2012 A new species of troglobitc loach (Cypriniformes, Balitoridae), Triplophysa Jiarongensis, From Guizhou, China.
Zhang, C.G. and Zhou, Y.H. Book 2016 Species diversity and distribution of inland fishes in China
Li, J., Lan, J.H., Chen, X.Y. and Du, L.N. Journal Article 2017 Description of Triplophysa luochengensis sp.nov. (Teleostei: Nemacheilidae) from a karst cave in Guangxi, China
Xu, T, Deng, H. and Zhou, J. Journal Article 2017 The cavefish Oreonectes jiarongensis can be induced to differentiate and recover under the light condition
Zhang, Y., Wang, Z., Zhang, Z., Wu, M.. Chen, J. and Zhao, Y. Journal Article 2018 The complete mitochondrial genome of Triplophysa brevibarba with phylogenetic consideration
Wu, W.J., He, A.Y., Yang, J.X. and Du, L.N. Journal Article 2018 Description of a new species of Triplophysa (Teleostei: Nemacheilidae) from Guizhou Province, China
Liu, X., Deng, H., Liu, Z. and Jiang, Z. Journal Article 2019 Reassignment of 'Triplophysa' jiarongensis (Cypriniformes: Nemacheilidae) to Oreonectes Günther, 1868
Huang, J.Q., Yang, J., Wu, Z.Q. and Zhao, Y.H. Journal Article 2019 Oreonectes guilinensis (Teleostei, Cypriniformes, Nemacheilidae), a new loach species from Guangxi, China
Zhao, L.-X., Liu, J.-H., Du, L.N. and Luo, F.G. Journal Article 2021 A new loach species of Troglonectes (Teleostei: Nemacheilidae) from Guangxi, China
Zhang, J.H., Long, R., Jing, Y.Y., Zhang, P., Xu, Y., Xiong, W., Zhu, Y.Q. and Luo, Y.P. Journal Article 2023 Loss of behavioral stress response in blind cavefish reduces energy expenditure