Characteristics of palinurids (Decapoda; Crustacea) in larval culture

Abstract

Complete development of phyllosomas was accomplished in Palinurus elephas, Panulirus japonicus, Jasus edwardsii and J. verreauxi. Larval development differs between species in duration and moult frequency as well as morphology. The highest percent survival was obtained during the phyllosoma stage for J. verreauxi. Phyllosomas of P. elephas were the most difficult to culture regardless of the fact that they hatch at a relatively advanced stage. Culture experiments were carried out to improve the percent survival of P. elephas. First instars of P. elephas exhibited vigorous predation upon the larvae of Japanese sandfish Arctoscopus japonicus. Duration of the first instar was shorter at 12.8 days when reared at 18 °C and percent survival was approximately 30%. Better results were obtained for first instars cultured in water inoculated with Chaetoceros sp. and fed enriched Artemia nauplii. Phyllosomas of J. edwardsii and P. japonicus were cultured without particular difficulty. Most distinguishing features of P. elephas is the heavily setose six or seven long spines on the distal edges of the scaphognathite of the second maxillae while only four long spines are found in other species. These facts suggest that phyllosomas of P. elephas are initially plankton feeders and from first instar become rapacious predators.