W gele h (1 resultados)

The phylogenetic position of Corambidae has been subject to much speculation. Most of the confusion has arisen from insufficient anatomical knowledge and from interpretations which have not followed the rules of Hennigian phylogenetic systematics. In this study, as a model system, the poorly known Chilean species Corambe lucea Marcus, 1959 is redescribed in detail: digestive, reproductive, central nervous, circulatory, and excretory systems are examined anatomically and histologically. New biological data are also given. After critical comparison with congeners, C. lucea is confirmed to be a valid species. Major organ systems of C. lucea are discussed comparatively and used to resolve phylogenetic relationships. Gill structure and circulatory system of the Corambidae are homologous to that of the Anthobranchia bauplan but not to the secondary gills and circulatory system of the Phyllidiidae. The similar lateral position of respiratory organs and a posteroventral anus in some Corambidae and Phyllidiidae is clearly due to convergence; the two groups are true doridoidean nudibranchs but there is no indication for a sistergroup relationship. Corambids are shown to belong to the monophyletic group Suctoria which is characterized by the unique and complex autapomorphies ?possession of a dorsal buccal pump? and ?possession of a large first lateral tooth with a long, denticulated hook? 14 pp., 13 figs, 4.…