Study of abundant and some reproduction traits of two species crabs Matuta victor (Fabricius, 1781) and Matuta planipes (Fabricius, 1798) in Gehrdo coast, Oman Sea

This study was done to investigate of abundance and some reproduction traits of Matuta victor and Matuta planipes on Gehrdo coast, the Oman Sea from December 2019 to November 2020. Overall, 310 crabs of M. victor and 297 crabs of M. planipes were collected. Sex ratio (M/F) was observed as 1.4:1 for M. victor and 1.7: 1 for M. planipes (p <0.05). Based on the results, the average carapace width and weight of male crabs were obtained more than female crabs for two studied species. In this study, the highest and lowest fecundity were 43423 eggs (carapace width of 26.7 mm and weight of 6.25 g) and 11635 eggs (carapace width of 28.55 mm and weight of 8.79 g) for M. victor and 45353 eggs (carapace width of 24.6 mm and weight of 6.35 g) and 14365 eggs (carapace width of 31.9 mm and weight of 10.29 g) for M. planipes. In two studied species, the result showed inversely relationship between egg number with carapace width and body weight. The results showed that there is an inverse relationship between temperature and gonadosomatic index for two studied species. The highest GSI was in February (10.71±6.44) and in October (5.41±2.13) for M. planipes and M. victor respectively. According to the results, abundance of M. planipes was more in autumn and winter while, abundance of M. victor was more in spring and summer.