DORIDS: GNATHODORIDOIDEA | PHANEROBRANCHIA | CRYPTOBRANCHIA

Dorid nudibranchs constitute the most diverse clade of opistobranch gastropods. Although members of this taxon are important in the study of biochemical compounds, and ecological and behavioral studies, their alpha toxonomy, higher classification, phylogenetic relationships and biogeography remain poorly known. More than one-third of the 6,000 species of opistobranchs are dorids. Of the approximately 2,000 species of dorids, 25-50% of the species within different genera are presently undescribed. The higher classification of dorid nudibranchs requires significant re-examination within the context of contemporary phylogenetic morphology. Many genera are based on taxa that lack apomorphic features and are probably paraphyletic. Opistobranchs have presented difficulties for phylogenetic studies owing to high levels of homoplasy. For this reason molecular and morphological data will be collected and analyzed to supplement known morphological information.