Morphology of the first zoeal stage of Macrobrachium surinamicum Holthuis, 1948 (Malacostraca, Decapoda, Palaemonidae) hatched in the laboratory

The first zoeal stage of the freshwater shrimp Macrobrachium surinamicum Holthuis, 1948 is described and illustrated based on hatchlings from an ovigerous female, collected in Rio Campupema, Abaetetuba, in the northern Brazilian state of Para, and compared with the first zoeae of several other species of the genus occurring in Brazil. Although the first zoeae of the different species of Macrobrachium are morphologically very similar, they can still be separated by a combination of morphological characters but only M. surinamicum has one smooth seta on the maxillular endopod. Although a complete larval series of M. surinamicum presently remains unknown, as pereiopods 3-5 and pleopods are absent, the outcome of this study suggests that the larval development of this species is extended and includes at least seven larval stages.