Study on the sexual maturation of male mud crab, with special focus on scylla olivacea

Abstract

Mud crab genus Scylla is a commercially important species that are widely distributed throughout the Indo-Pacific region, including Malaysia (Ikhwanuddin et al., 2011). Currently, four species of mud crabs within the genus Scylla are recognized worldwide (Keenan et al., 1998). However, only three species are officially reported in Malaysian waters (i.e. S. paramamosain, S. tranquebarica and S. olivacea) (Ikhwanuddin et al., 2011). Out of these three species, S. olivacea is the most dominating species and can be found in almost all coastal areas of Malaysia. Also known as orange mud crab or locally known as ‘ketam sepit merah’ due to its noticeable vibrant red-orange colour on its front chela, S. olivacea is smaller in size but hardier compared to the other species within the same genus (Waiho et al., 2015). Predominantly inhabits intertidal mangrove forests with fluctuating salinity, S. olivacea are commonly found along mangrove banks and seek shelter among the branches of mangroves.