Phylobiogeography of two Caribbean ochyroceratid genera: Theotima and Ochyrocera

ABEL PÉREZ GONZÁLEZ; GRETA BINFORD; SASHA BISHOP; INGI AGNARSSON

Golden

Congreso; 20th International Congress of Arachnology; 2016

International Society of Arachnology

The Caribbean island system is a region of high biological diversity. The islands are home to much unknown arachnid diversity that has evolved in the context of complex biogeographical histories of the islands and associated land masses. This study analyzes patterns of diversity in the family Ochyroceratidae, a relatively uncharacterized group in the Caribbean. Sampling is centered on two genera: Theotima, a smaller, parthenogenic genus, and Ochyrocera, a nonparthenogenic genus. Though there is minimal documented evidence of their dispersal capabilities, both genera are small, leaf-litter dwelling spiders with biologies consistent with poor dispersers. We use phylogenetic analyses to comparatively assess genetic structure and biogeographic pattern of these two genera. Phylogenies use two mitochondrial genes (COI and 16s) and two nuclear genes (28s and H3) with representation of a total of 200 individuals collected from across the Caribbean islands and southern Mexico. Both genera display high levels of genetic depth, however patterns of relatedness in Ocherocera reflect more island-, and region-level genetic structure than Theotima. These patterns suggest the possibility of higher dispersal rates in Theotima relative to Ochyrocera. Genetic structure of COI suggests approximately 29 distinct genetic lineages within our sampled taxa, greatly expanding the sampling beyond 16 known species within the region.