Meeting Abstract
120.1 Monday, Jan. 7 Morphology, molecules, molluscs, and modern monographs: A revisionary systematics case study KOHN, AJ; Univ. of Washington kohn@uw.edu
Taxonomy, classification and phylogenetic interpretation of shelled marine molluscs have traditionally relied primarily on shell characters, the most durable and often the only ones available for study. However, recent advances in molecular genetics have drastically altered this tradition. In the hyperdiverse neogastropod genus Conus of >,700 extant species, DNA sequences provided the first species-level phylogenetic hypotheses in1999. Inconsistencies between molecular data and shell morphology-based taxonomy soon became apparent both in Conus and elsewhere in the superfamily Conoidea. Concurrently, increasing attention to other morphological characters, particularly of the hypodermic needle-like radular teeth, indicates greater congruence with molecular data than the latter have with shell characters. Here I report on a systematic revision of the extant species of western Atlantic Conus north of Brazil, applying shell, radular, and molecular characters as far as possible to the 263 nominal species described from 1758 to 2011. For the 53 species whose validity the results support, the study estimates infraspecific variation and differentiates each species as clearly as possible from its most similar congeners. It describes shell and radular tooth characters quantitatively and analyzes key mitochondrial genes both as taxonomic characters and to evaluate phylogenetic relatedness among species. I summarize the current species-level phylogeny of western Atlantic Conus, but molecular genetic information is presently limited to small sample sizes and fewer than half the species. Molecular data have revealed the existence of cryptic species with indistinguishable shell morphologies in other regions, and future work will most likely increase the number of known valid western Atlantic species.
