Growth pattern variability in invasive non-indigenous mosquitofish Gambusia holbrooki(Girard, 1859) from southern Caspian basin, Iran

The study was conducted to determine the allometry variability of mosquitofish based on 10987 specimens collected from 11 localities in thesouthern Caspian Sea basin in summer 2021. The estimated b-values range from 2.414 for males from thecoastal lagoon of Gorgan Bay to 3.911 for the population from theSorkhroud River. In the basin, theoverall mean of the b coefficient was 3.190±0.413. Thegrowth patterns of most considered groups were positive allometric. The form factor a3.0indicated that body shapes were different between the areas