C. X. Xie

Threatened fishes of the world: Gobiocypris rarus Ye and Fu, 1983 (Cypinidae)

Conservation status: Endangered, China Red Data book of endangered animals (Yue and Chen 1998). Identification: A small freshwater Cypinidae (maximum 83 mm), slightly compressed body, round belly, short snout, incomplete lateral line. Lateral line scales 31–34, D: iii, 7–8; A: iii, 6–7; P: i, 11–12; V: ii, 7–8, C: 17, two rows pharyngeal teeth, barbel absent, small forked caudal fin, no keel on abdomen (Ye and Fu 1983). Gray dorsum, white belly, a longitudinal lateral yellowish zone. This zone becomes brighter, and small nuptial organs on operculum and pectoral fins in spawning males (Wang 1992). Distribution: Endemic to southwest China, in Liushahe River and some rivulets in Hanyuan county and Chengdu city of Sichuan province. Habitat and ecology: Gregarious in small water systems with a half-mud, half-stone bottom such as paddyfields, ditches, and rivulets, especially in weedy areas with low water flow. The species eats some small invertebrates, such as the aquatic earthworms (Oligochaeta). It is eurythermal, tolerates 1 to 35°C, and 0.50 mg·l oxygen and 70 mg·l carbon dioxide at 25°C (Wang 1995). Easy to be fed and reproduced, so it is a good experimental animal in China. Reproduction: Minimum age of sexual maturity 4 months. Females spawn between March and November, when water temperature above 14°C (Wang 1999). Fertilized eggs are ball, transparent, sticky, heavier than water and 1.25–1.70 mm in diameter (Wang 1992). Threats: Narrow habitat range and limited natural population, pesticides and ecological instability have caused rapid declines (Yue and Chen 1998). Conservation action: No specific action has been taken, not IUCN listed. Conservation recommendation: On-site conservation and restriction of fishing during its spawning season. Studies to estimate population size and structure, life history and genetic diversity, are needed for management and protection. Environ Biol Fish (2009) 86:107–108 DOI 10.1007/s10641-007-9284-8