LIVING GENERA OF SEA PENS (COELENTERATA, OCTOCORALLIA, PENNATULACEA) - ILLUSTRATED KEY AND SYNOPSES

An illustrated dichotomous kev and synopses of the 32 genera of living pennatulacean octocorals are presented, which incorporate new morphol ogical and distributional data from the examination of recently collec ted material. In addition, a key to the 15 extant families, lists of v alid genera, synonyms, and a table of comparative characters are also included. Lastly, a revised classification and phylogenetic considerat ions are presented. Preliminary investigations indicate that the tradi tional higher classification scheme of the Pennatulacea is inadequate for reasons of paraphyly and intermediate taxa, that tend to negate pr ecise distinctions between some of the nominal higher taxa. Of the app roximately 436 described species of sea pens worldwide, only 186 (or 4 3%) are estimated to be valid. In addition, several undescribed specie s have recently been discovered, and others will no doubt be discovere d in the future. It is therefore estimated that tile extant pennatulac ean fauna of the world comprises approximately 200 species in 32 gener a.