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An unidentified final-stage scyllarine phyllosoma larva possessing a unique red-spotted pattern of chromatophores was found in sublittoral waters off Yamaguchi Prefecture, Japan. The phyllosoma was reared in the laboratory, metamorphosed into a nisto, and then first juvenile stage. DNA barcoding analysis using 16S rRNA gene identified these stages as the scyllarid (slipper) lobster Petrarctus brevicornis (Holthuis, 1946). As these stages were previously unknown, the morphology of the final-stage phyllosoma, nisto, and first stage juvenile are described and illustrated.

In the marine realm, it is important to understand the connectivity and population dynamics of commercially exploited species; this information promotes sustainable fishing practices. The large slipper lobster, Scyllarides latus (Latreille, 1803), is a commercially valuable crustacean that has been over-exploited in many areas throughout its distribution range in the northeastern (hereafter NE) Atlantic and the Mediterranean. Here, we report the first molecular population genetic study of S. latus based on 9 nuclear microsatellite loci. A total of 128 specimens of S. latus were collected in the Western Mediterranean (2 locations) and four regions (13 locations) in the NE Atlantic, including Southern Portugal and the Macaronesian archipelagos of Azores, Canary Islands and Cape Verde. Maximum number of alleles per locus ranged from 4 to 14, and observed heterozygosity per locus ranged from 0.143 to 0.795 (0.539 ± 0.087, mean ± SE). Pairwise region estimates of FST, RST and Dest were very low (

The morphology of the final phyllosoma larval stage of the slipper lobster Scyllarus pygmaeus is described and illustrated based on larvae captured from Mediterranean waters and compared with those described in other Scyllaridae. These larvae were always found in deep waters (>200 m). Nucleotide sequence analysis of a region of the nuclear 28S rDNA gene identified these larvae as S. pygmaeus, the morphology of which had been previously un-described. An intensive review revealed a misidentification of Scyllarus arctus larvae in the literature during the last 180 years, since the identification of S. pygmaeus larvae as Chrysoma mediterraneum. Detailed examination indicated that the final-stage larvae examined belonged to a clearly defined phyllosoma larval group within the genus Scyllarus, morphologically very similar to some phyllosoma larvae collected from Japan, Hawaiian Islands, New Zealand or Juan Fernandez Islands. This constitutes the first complete description of a phyllosoma stage of a member of the family Scyllaridae, with the specific identity of the larva being validated with molecular techniques, This work was supported by a pre-doctoral fellowship awarded by the Autonomous Government of Catalonia to F.P. (2006FIC-00082). Research was funded by project CGL2006-13423 from the Ministerio de Educación y Ciencia. The authors are part of the research groups 2005SGR-00191 and 2005SGR-00995 of the Generalitat de Catalunya

Digestive capabilities of the commercially important slipper lobster Thenus orientalis were determined by comparing the range and concentration of digestive enzymes produced with the preferred diet of this and other slipper lobster species. Thenus orientalis is a specialized predator of bivalve molluscs, which are located by probing and digging the substratum. The edible flesh is removed by wedging, a progressive prying the shell valves apart, using the sharp keratinized pereiopod dactyls. The range and concentration of digestive enzymes produced reflects the carnivorous diet of T. orientalis. The proteases trypsin and chymotrypsin are produced in high concentrations, the former representing a considerable proportion (up to 13%) of digestive gland protein. Detection of a-amylase and a-glucosidase indicates that T. orientalis is capable of hydrolyzing glycogen, the major storage polysaccharide in bivalve adductor muscle. These features indicate a digestive capability specialized for the hydrolysis of flesh. Significant N-acetyl β-D-glucosaminidase activity revealed an ability by T. orientalis to hydrolyze chito-oligosaccharides and suggested that it can digest chitin from crustacean exoskeletons that have been found in the diet of other scyllarids. Digestive fluid pH (5.9) is consistent with the acid pH optima of carbohydrases, verifying that they are well adapted for extracellular digestion.

Of 565 individuals of Scyllarides latus (Latreille, 1803) from landings on Pico Island, Azores, during the summer of 1982, 55% were males, and 45% females, of which 75% were ovigerous. The mean carapace length for males and females was 92.4 mm and 94.8 mm, respectively. The weight/length relationship for males is expressed by W = 0.0020L2.825 and for females W = 0.0065L2.580. The number of eggs per brood varied from 151-356,000. The egg-bearing period lasted for approximately 6-8 weeks, with spawning starting in late June. Eggs hatched into naupliosoma larvae. The naupliosoma stage observed in an aquarium lasted approximately 40–60 min. The larvae swam with the help of their antennae. The main diet of S. latus in summer consists of limpets (Patella spp.). The principal predator of the commercial stock is the dusky grouper (Epinephelus guaza). The lobsters migrate to deeper water at the beginning of October and return to the coast in May. Molting takes place in winter. In aquaria, 7 individuals molted between 28 November and 28 February. After results of this study were known, the Secretariat of Agriculture and Fisheries of the Regional Government of the Azores changed the closed season for catching this species from 1 August-30 April to 1 May-31 August.