"Exolysosomes," enzyme-containing vesicles in the ecdysial space of molting crabs.

Free vesicle-like bodies (VLBs) present in the ecdysial space of cuticle regions undergoing degradation during preecdysis of the Atlantic shore crab Carcinus maenas have been interpreted either as infectious organisms or as secretion structures associated with degradation of the old cuticle. Ultrastructural, cytochemical, and immunocytological investigations were performed to test these hypotheses and to see whether VLBs are peculiar to this crab species. Similar VLBs were systematically found in two other preecdysial crabs, Cancer pagurus and Macropipus puber.