These prawns can reach remarkable sizes, with males growing up to 33 cm and females up to 29 cm. The difference in size between males and females is largely due to the social structure and dominance hierarchies present in the species. Males grow larger and develop more robust physical features, such as the enlarged claws, to assert dominance within the group. They typically exhibit a brownish color, but younger and smaller individuals may display a greenish hue with subtle vertical stripes, a trait linked to camouflage in their natural habitats.
A distinctive feature of M. rosenbergii is its long rostrum, which has 11 to 14 dorsal teeth and 8 to 11 ventral teeth. These prawns possess an elongated first pair of walking legs that are delicate and end in claws primarily used for feeding. In contrast, the second pair of walking legs, especially in males, is far more developed, covered in dense bristles, and often appears velvety. These large claws serve not only as tools for defense but also as a signal of dominance, with their color changing based on the prawn’s social rank.
The species’ life cycle is also notable, as M. rosenbergii requires brackish water during its larval stage before transitioning to freshwater as juveniles. This adaptability makes it easier to rear them in a controlled aquaculture environment, contributing significantly to the species’ success in commercial farming.
Macrobrachium rosenbergii: A Key Species in Aquaculture
