Meeting Abstract

26.6  Wednesday, Jan. 5  Phylogeny and divergence times of Pancrustacea based concatenated analysis of 200 genes and morphology OAKLEY, Todd H.*; LINDGREN, Annie R.; WOLFE, Joanna M.; ZAHAROFF, Alexander K.; JUAREZ, Bryan; Univ. of California, Santa Barbara; Univ. of California, Santa Barbara; Yale University; Univ. of California, Santa Barbara; Univ. of California, Santa Barbara oakley@lifesci.ucsb.edu

The Pancrustacea (crustaceans plus hexapods) are a riotously speciose, morphologically disparate, and ancient clade of animals. Furthermore, some pancrustaceans, like the Ostracoda, have an outstanding stratigraphic record. Understanding how and when these important animals and their morphologies evolved is a long-standing goal in evolutionary biology, yet their phylogenetic relationships remain controversial. We added new pyrosequencing transcriptome data from 8 disparate ostracod crustaceans to existing EST and mitochondrial genome data, resulting in over 200 gene families analyzed. In addition, we coded more than 150 morphological characters (most previously published), for extant and extinct pancrustaceans. We concatenated all data together for maximum likelihood phylogenetic analyses. Notable preliminary results indicate support for Branchiopoda over Xenocarida as the sister group to Hexapoda; monophyly of Ostracoda (a result never obtained previously with molecular data); monophyly of Oligostraca as the sister group to all other Pancrustacea; and the ancient (Cambrian or earlier) origins of multiple major Pancrustacean groups. The phylogeny of Pancrustacea is likely to remain controversial for some time, but high throughput sequencing technologies are allowing the rapid accumulation of data, which should promote progress toward consensus.