First description of the megalopa stage of the portunid crab Monomia argentata (A. Milne-Edwards, 1861) (Crustacea: Brachyura: Portunidae)

Megalopae of the portunid crab, Monomia argentata (A. Milne-Edwards, 1861), were collected from Taiwan waters and their identification was confirmed by DNA barcoding technique. The morphology of this megalopa is described and illustrated. The megalopa has more setae on the appendages and exhibits a spine on the cheliped carpus as compared to the known description of M. rubromarginata (Lanchester, 1900). Furthermore, the megalopae of Monomia and Portunus Weber, 1795 are remarkably similar.