Biology of the tropical bivalve Asaphis deflorata (Linné, 1758)

Asaphis deflorata in the Bahamas is found in dense concentrations among rocky gravel in the highest intertidal zone, where it is the only bivalve present. Sexes are separate and sexual maturity is reached after 2 to 3 years at a size of 25 mm or greater. Mass spawning occurs in late summer and larvae develop to the pediveliger stage within 10 to 13 days. This stage is very brief, lasting only 24 h. Estimates of long-term sustained growth rates are 10 to 15 mm/year and fit the von Bertalanffy growth equation using probit and computer analysis of size frequency distributions. Natural mortality relating to both size-dependent predation and size-independent catastrophic burial by sand is evident in empty shell assemblages.