Seasonal changes in gonadosomatic index, hepatosomatic index and condition factor of the female Geno tooth-carp, Aphanius ginaonis

A dearth of basic biological information, especially about reproductive traits for the Geno tooth-carp, Aphanius ginaonis, currently hinders the proper management efforts for this valuable species. This fish is an endemic cyprinodont that exclusively lives in the Geno hot spring. In this study, reproductive biology of female A. ginaonis was studied, based upon the annual changes in gonadosomatic index (GSI), hepatosomatic index (HSI) as well as condition factor (K). A total of 84 females were captured monthly between November 2012 and October 2013. Results demonstrated that GSI was the lowest value in summer with average of 7.24 ± 0.30. In other seasons there were no significant differences. The average of HSI in spring (4.56 ± 0.17) was significantly higher than summer (3.69 ± 0.12) and autumn (3.84 ± 0.13) whereas it did not show any differences with winter (4.12 ± 0.19). Condition factor with average of 1.50 ± 0.01 demonstrated a uniform trend throughout the year. Considering all these results revealed that A. ginaonis is active reproductively in all seasons and this fish is a batch spawner. All these findings represent an important basis for further investigation on the reproductive biology of this fish and may assist to improve proper management to protect this valuable species.