Meeting Abstract

P3.198  Tuesday, Jan. 6  A phylogenetic examination of social monogamy in stomatopod crustaceans WRIGHT, M.L.*; SWINSTROM, K.; CALDWELL, R.L.; Univ. of California, Berkeley; Santa Rosa Junior College; Univ. of California, Berkeley

The Lysiosquilloidea, a super-family of stomatopod crustaceans, includes several socially monogamous genera, providing an unique system to study the evolution of monogamy. Social monogamy is maintained by different mechanisms within these genera. In the family Lysiosquillidae, energetic costs of making burrows, predation risks, and spousal feeding behaviors all likely contribute to the maintenance of monogamy. In contrast, selection for biparental care maintains monogamy in some species in the Nannosquillidae. Using comparative phylogenetic methods, I examined the evolution of social monogamy in the Lysiosquilloidea. To test the monophyly of the Lysiosquilloidea and provide more internal resolution of the clade for future studies, I used the mitochondrial loci 16S and 12S, as well as a morphological matrix (Ahyong 2000), to create phylogenies using maximum parsimony and Bayesian tree-building methods. The monophyly of Lyiosquilloidea was well-supported in the analyses. The internal branching of the four families was consistent in both analyses, indicating that Nannosquillidae and Tetrasquillidae are sister clades, and that Lysiosquillidae is sister to all other Lysiosquilloidea. I then reconstructed the evolution of social monogamy on the Bayesian tree (MK1) and the parsimony trees (MP). Social monogamy has originated at least three times in stomatopod crustaceans, suggesting that further phylogenetic comparative studies on the correlations between monogamy, environment, and biparental care in this group will be fruitful. The relationships between superfamilies, as classified by Ahyong (2000, 2001), were not stable in this analysis and should be re-examined using more characters, especially molecular and genomic data.