PHYLLOSOMA LARVAE AND THE PHYLOGENY OF PALINUROIDEA (CRUSTACEA, DECAPODA) - A REVIEW

A review of larval morphology of some 50 species belonging to 15 of th e 16 existing genera of Palinuroidea is presented. The taxonomic value of larval characters of the group is discussed, and a phylogenetic sc heme of the whole group has been attempted. Phylogenetic and phenetic data obtained during this review show good agreement with a previously published evolutionary scheme for the Palinuridae based on adult char acters, although Palinurus seems to be a more primitive genus than Pal inustus and Justitia. From the point of view of larval morphology, Pal inurellus (Synaxidae) seems to be the most primitive genus. Data on ev olution of the Scyllaridae show three well differentiated groups: the more primitive (as typified by the larvae) Scyllarides-Arctides-Parrib acus and Ibacus-Evibacus groups and the more specialized Thenus-Scylla rus group. Larval morphology also suggests that Parribacus is closer t o Scyllarides and Arctides than to the Ibacus-Evibacus group. Evolutio n in Palinuroidea is seen as a process of radiation of the deep-water genera to coastal waters with a progressive shortening of larval life, although secondary trends towards shortening of larval life have also occurred in the more primitive deep-water genera (Puerulus, Linuparus and Palinurus).