Meeting Abstract
116.4 Tuesday, Jan. 7 11:00 A life-history approach to describing species diversity of nemerteans in the NE Pacific HIEBERT, T.C.*; MASLAKOVA, S.A.; Oregon Institute of Marine Biology, Univ. of Oregon; Oregon Institute of Marine Biology, Univ. of Oregon terrah@uoregon.edu
Recent estimates suggest that between one third and nine tenths of marine eukaryotic diversity is undescribed. Although most marine invertebrates have biphasic life cycles with planktonic larvae and benthic adults, larval stages are rarely part of biodiversity assessments. We have evaluated the nemertean diversity of the Oregon coast based on regular surveys of both the adults and larvae since 2008, connecting the two life history stages with DNA sequence data. About 65 intertidal species are reported from central California to Oregon, and the nemertean fauna of this region is thought to be well characterized. Surprisingly, our results suggest that the local diversity of this phylum is at least double what is currently known. We found many species new to science, and detected (mostly as larvae in the plankton) species previously known only from other parts of the world. About half of all larval types we have collected remain unidentified because we have not yet encountered their adults. This illustrates an important point for biodiversity studies of other groups of marine invertebrates worldwide: certain species are likelier to be encountered as larvae in the plankton than as adults. Sampling both adults and larvae may reveal a much greater diversity than if only one of the life history stages is surveyed. Additionally, we discovered several new types of nemertean larvae, which is relevant to our understanding of larval evolution. Finally, while nemertean larvae often have species-specific morphology, the general morphotypes appear to characterize clades of closely related species. This means that larval identification not only reveals hidden diversity, but may also help to revitalize the systematics of the group by infusing larval characters into an adult-centric taxonomy.
