Meeting Abstract
Glossodoris nudibranchs (Mollusca: Gastropoda: Opisthobranchia: Chromodorididae) are brightly colored sea slugs that derive their toxic chemical defenses from their sponge prey. Sesterterpenoid compounds exhibit a wide range of biological properties that aid in organism defense including cytotoxicity, anti-microbial, and ichthyotoxicity. Nudibranch tooth morphology has traditionally been used for taxonomic classification, but with recent advances in molecular systematics, many of these relationships have changed. A recent mitochondrial phylogeny of the Chromodorididae revealed the genus Glossodoris to be polyphyletic. In this study, 50 individuals comprising 18 taxa were used to build a more robust phylogenetic tree of Glossodoris. Molecular phylogenetic analyses were performed on three loci: mitochondrial COI (658 bases), mitochondrial 16S (edited: 465 bases), and nuclear 28S (edited: 851 bases). Maximum likelihood and Bayesian statistical analyses verify the previously hypothesized evolutionary relationships within Glossodoris. Morphological analysis of mantle dermal formations, radular structures, and reproductive systems were used to confirm the molecular phylogeny. Additionally, preexisting chemical data has been amassed and will be used to determine if more closely related Glossodoris share chemical profiles. These results provide insight into the evolution of chemical defense sequestering in nudibranchs and allow for a deeper understanding of coevolution and prey choice of Glossodoris nudibranchs.
