Friday, May 26, 2023

[Herpetology • 2023] Hynobius bambusicolus • An Isolated and Deeply Divergent Hynobius Species (Caudata: Hynobiidae) from Fujian, China

Hynobius bambusicolus  Wang, Othman, Qiu & Borzée, 

in Wang, Othman, Qiu, Lu, Prasad, Dong, Lu et Borzée, 2023.
虚竹小鲵  ||  DOI: 10.3390/ani13101661 

It is important to describe lineages before they go extinct, as we can only protect what we know. This is especially important in the case of microendemic species likely to be relict populations, such as Hynobius salamanders in southern China. Here, we unexpectedly sampled Hynobius individuals in Fujian province, China, and then worked on determining their taxonomic status. We describe Hynobius bambusicolus sp. nov. based on molecular and morphological data. The lineage is deeply divergent and clusters with the other southern Chinese Hynobius species based on the concatenated mtDNA gene fragments (>1500 bp), being the sister group to H. amjiensis based on the COI gene fragment, despite their geographic distance. In terms of morphology, the species can be identified through discrete characters enabling identification in the field by eye, an unusual convenience in Hynobius species. In addition, we noted some interesting life history traits in the species, such as vocalization and cannibalism. The species is likely to be incredibly rare, over a massively restricted distribution, fitting the definition of Critically Endangered following several lines of criteria and categories of the IUCN Red List of Threatened Species.

Keywords: Hynobidae; species description; bamboo forest

Natural habitat and oviposition site for Hynobius bambusicolus sp. nov.
The site is in Quxi village, Liancheng county, People’s Republic of China.

Hynobius bambusicolus sp. nov. Wang, Othman, Qiu and Borzée

Identity, diagnosis, and distribution:  To date, the species is known from its type locality only, Quxi village, Liancheng county (Figure 5). Larvae are typical of Hynobius larvae in shape and color and do not differ from other Hynobius species in the region in their development (Figure 10). The embryos develop in egg sacs (Figure 10A), larvae first swimming freely with balancers (Figure 10B; shown at day 16), then develop non-functional hind limbs (Figure 10C; shown at day 69), which slowly become functional (Figure 10D,E; shown at day 74 and 77), and the gills regress before metamorphosis (Figure 10F; shown at day 84). Juveniles are brown, darkening with age, with a large variation in blue speckles on their dorsum, which disappears as they age (Figure 9). Adults of the species are uniform dark chocolate, with light grey and bluish speckles on the venter (Figure 11). Identification is best assessed based on location, although discrete morphological characters include the combination of 10 or fewer costal grooves with a total length > 180 mm (Figure 6). To facilitate the identification and further study, the OBJ file of this model can be downloaded (Supplementary File S1). The visual representation of the model is provided in Appendix A (Figure A1).

Etymology: The species was first found in Quxi village, Liancheng county, in the west of Fujian province in China. The name H. bambusicolus sp. nov. comes from the habitat of the holotype and the only known habitat type for the species: bamboo forests
The vernacular name of the species, Fujian Bamboo Salamander, reflects the scientific name of the species, as does its Chinese name: 虚竹小鲵 (pronounced: Xū Zhú Xiǎo Ní). This salamander is named after a main character from Jin Yong’s swordsman fiction “The semi gods and semi devils”, with Xuzhu (虚竹) as the main character and where “虚” [xū] means humble, and “竹” [zhú] means bamboo. This character, Xuzhu, was an unknown Shaolin monk, but he inherited the powers of the leader of the Carefree by coincidence and started its legendary journey.
กิมย้ง: แปดเทพอสูรมังกรฟ้า - 天龙八部 - Semi-Gods and Semi-Devils 
(พ.ศ. 2506-2509)

 Zhenqi Wang, Siti N. Othman, Zhixin Qiu, Yiqiu Lu, Vishal Kumar Prasad, Yuran Dong, Chang-Hu Lu and Amaël Borzée. 2023. An Isolated and Deeply Divergent Hynobius Species from Fujian, China. Animals. 13(10); 1661. DOI: 10.3390/ani13101661
(This article belongs to the Special Issue Salamanders: Distribution, Diversity, and Conservation)
New salamander species from Southern China! 中国南方小鲵新种
Simple Summary: What does not have a name is difficult to understand and protect. Upon the unexpected discovery of an Hynobius salamander in Fujian province, China, we worked on understanding its relationship with other species and ultimately describing it. Please welcome the Fujian Bamboo Salamander to science, a segregated species based on genetics and morphology. While it is related to other southern mainland Chinese species, it may have diverged earlier and share some similarities with morphology and behavior with the Anji salamander. The Fujian Bamboo Salamander is special as it produces vocalization when under threat. The species is, however, incredibly rare, fitting the definition of Critically Endangered in the IUCN Red List of Threatened Species.