Mechanisms of crustacean egg hatching: Evidence for enzyme release by crab embryos


Journal Article

During the summer of 1989, we examined mechanisms of egg hatching in three species of brachyurans that occupy different habitats as adults near Beaufort, North Carolina, USA:Neopanope sayi (Smith) (subtidal), Uca pugilator (Bosc) (intertidal) and Sesarma cinereum (Bosc) (supratidal). Results of casein assays indicated that embryos of all species release proteolytic enzymes near the time of egg hatching. Species differences in specific enzyme activity were suggested, with increased activity in the more terrestrial crabs. Embryos of N. sayi released enzymes several hours before larval release by the female, while U. pugilator and S. cinereum released enzymes closer to the time of larval release; enzyme release coincided roughly with time of egg-membrane breakage in all species. Direct observations of hatching showed a sequence of outer-membrane breakage apparently followed by inner-membrane breakage and emergence of the larva. Egg volumes increased most during early and/or mid-stages of development, with a marked slowing of the increase during the several days before hatching. Thus, a gradual osmotically-driven increase in water content may also be involved in egg hatching. © 1991 Springer-Verlag.

Full Text

Duke Authors

Cited Authors

  • De Vries, MC; Forward, RB

Published Date

  • June 1, 1991

Published In

Volume / Issue

  • 110 / 2

Start / End Page

  • 281 - 291

Electronic International Standard Serial Number (EISSN)

  • 1432-1793

International Standard Serial Number (ISSN)

  • 0025-3162

Digital Object Identifier (DOI)

  • 10.1007/BF01313715

Citation Source

  • Scopus