Meeting Abstract

48.2  Tuesday, Jan. 5  Seastars across the oceans: Molecules help untangle biogeographic patterns for a species-rich genus, Henricia EERNISSE, D.J.*; CORSTORPHINE, E.; CLARK, R.N.; STRATHMANN, M.F.; Calif. State Univ., Fullerton; Univ. of Guelph; Santa Barbara Museum of Natural History; Friday Harbor Labs, Univ. of Washington deernisse@fullerton.edu

Over 100 recognized or newly discovered species of Henricia Gray, 1840 have a globally widespread anti-tropical distribution with especially impressive diversity in the northern temperate latitudes. Although Henricia has long been notorious for its taxonomic difficulty, we have made considerable progress by studying morphology while also sequencing portions of the mitochondrial 16S and COI gene regions. By collaborating to pool our separate regional molecular data sets, we have found that Henricia diversification extends across ocean basins. Besides our emphasis on both temperate coasts of North America, we have included representatives of Henricia from the Aleutian Islands, Japan, England, New Zealand, and South Africa. Some species were found to be widespread, for example along the entire Pacific coast between Baja California and southeastern Alaska, or with a trans-Arctic distribution. In contrast, the Pacific Northwest Henricia fauna is comprised of a surprisingly high proportion of co-occurring endemic species. Each of at least two species from New Zealand has a phylogenetic affinity with particular northern hemisphere counterparts, rather than with each other. Perhaps the cool deep-water habitat of the particular particular New Zealand species included has permitted historical dispersal across the tropics. Likewise, our analysis has revealed several intriguing phylogenetic connections across the Arctic with varying levels of genetic divergence.