Size at onset of sexual maturity and onset of spawning in female Panulirus homarus (Crustacea: Decapoda: Palinuridae) in Sri Lanka

Abstract

The average length at which female spiny lobsters Panulirus homarus attain sexual maturity was determined in Sri Lanka from 1986 to 1988 by observing changes in length of the tail, which later provides the substratum for attachment of fertilized eggs. Results were confirmed by observing the presence of spermatophores on the females' sternum. The size at onset of oviposition (spawning) was estimated by considering the '50% ovigerous' level. Results indicate that female P. homarus attain sexual (gonad) maturity afr\ter a rostral carapace length (RCL) of between 38 and 47 mm is reached. The size at onset of oviposition (spawning) was estimated as 59.5 mm RCL.