The oocyte development in Macrobrachium amazonicum (Heller, 1862), a freshwater palaemonid shrimp from Central Amazonia is described. This process is similar to thatof Macrobrachium acanthurus (Wiegmann, 1836). The earliest phases occupy the inner ovarian region, while the vitellogenic and the mature phases are found in the outer one. Both post-ovu-latory follicles and follicular cells morphologies are also described and illustrated.
Freshwater shrimp; Palaemonidae; Macrobrachium; Oocyte development; Amazon Region