Sinocyclocheilus xingrenensis (Cypriniformes, Cyprinidae), a new underground fish from Guizhou Province, Southeastern China

Abstract

This study describes a new species, Sinocyclocheilus xingrenensis sp. nov., collected from a cave near Xingren City, Guizhou Province, China. Morphologically, the new species can be distinguished from the 80 species currently assigned to the genus Sinocyclocheilus by a combination of the following characteristics: absence of horn-like structures and indistinct elevation at the head-dorsal junction; body scaleless, with irregular black markings scattered above the lateral line; tip of pectoral fin not reaching the pelvic fin origin; tip of pelvic fin not reaching the anus; lateral line complete and curved, with pores 65–77; tip of maxillary barbel reaching the anterior margin of the operculum; and six rakers on the first gill arch. Phylogenetic trees constructed based on mitochondrial genes indicate that the new species represents an independent evolutionary lineage with relatively large genetic differences of 2.8–9.0% for the mitochondrial Cyt b and 2.7–8.5% for ND4.