Prolixicheilus, Zheng, Lan-Ping, Chen, Xiao-Yong & Yang, Jun-Xing, 2016

Zheng, Lan-Ping, Chen, Xiao-Yong & Yang, Jun-Xing, 2016, Molecular systematics of the Labeonini inhabiting the karst regions in southwest China (Teleostei, Cypriniformes), ZooKeys 612, pp. 133-148 : 139-140

Taxon classification Animalia Cypriniformes Cyprinidae

Prolixicheilus gen. n.

Type species.

Pseudogyrinocheilus longisulcus Zheng, Chen & Yang, 2010 (Fig. 2A).

Etymology.

From the Latin adjective prolixus, meaning broad, stretched far out, and the Greek noun cheilos meaning lip, an allusion to the broad lips of the type species. Gender masculine.

Diagnosis.

Prolixicheilus can be distinguished from all other genera of labeonins by its peculiar morphology: papillate rostral fold and lower lip, evaginating and triangular; rostral fold pendulous, expanded ventrally, posterior margin non-fimbriate; lower lip with a straight posterior margin; upper lip vestigial; postlabial grooves prolonged, and extended anteromedially close to anterior end of middle lower lip, but not meeting with its counterpart; posterior margin of lower lip free; lateral-line scales 40-42; a longitudinal dark stripe along lateral line on flank; body laterally compressed.

Remarks.

Prolixicheilus can be easily distinguished from Pseudogyrinocheilus by the following combination of characteristics: postlabial grooves prolonged, and extended anteromedially close to anterior end of middle lower lip, but not meeting with its counterpart (only restricted at corners of mouth); posterior margin of lower lip free (vs. connected with chin); lateral-line scales 40-42 (vs. 45-49); a longitudinal dark stripe along lateral line on flank (vs. absent); body laterally compressed (vs. cylindrical). In addition, although Pseudogyrinocheilus longisulcus and Cophecheilus bamen are genetically closely related, Pseudogyrinocheilus longisulcus is readily distinguished from the species of Cophecheilus by the following combination of characteristics: rostral fold and lower lip evaginating (vs. not evaginating); rostral fold pendulous, expanded ventrally (vs. not pendulous, rostral cap with a shallow, arched, subdistal depression extending nearly the full length of its ventral edge); rostral fold and lower lip broad and fully papillated (vs. only margin papillated); posterior margin of lower lip free (vs. connected with chin); lateral-line scales 40-42 (vs. 43-48).

Distribution.

Prolixicheilus longisulcus has been only recorded in an unnamed stream in Lutong Village, Jingxi Co., Guangxi. The stream belongs to Zuojiang River, a tributary of Pearl River.