Island–to–Island Vicariance, Founder–Events and within–Area Speciation: The Biogeographic History of the Antillattus Clade (Salticidae: Euophryini)

Abstract

The Caribbean Archipelago is a biodiversity hotspot that plays a key role in developing our understanding of how dispersal ability affects species formation. In island systems, species with intermediate dispersal abilities tend to exhibit greater diversity, as may be the case for many of the salticid lineages of the insular Caribbean. Here, we use molecular phylogenetic analyses to infer patterns of relationships and biogeographic history of the Caribbean endemic Antillattus clade (Antillattus, Truncattus, and Petemethis). We test if the timing of origin of the Antillatus clade in the Greater Antilles is congruent with GAARlandia and infer patterns of diversification within the Antillattus clade among Cuba, Hispaniola, and Puerto Rico. Specifically, we evaluate the relative roles of dispersal over land connections, and overwater dispersal events in diversification within the Greater Antilles. Time tree analysis and model-based inference of ancestral ranges estimated the ancestor of the Antillattus clade to be c. 25 Mya, and the best model suggests dispersal via GAARlandia from northern South America to Hispaniola. Hispaniola seems to be the nucleus from which ancestral populations dispersed into Cuba and Puerto Rico via land connections prior to the opening of the Mona Passage and the Windward Passage. Divergences between taxa of the Antillattus clade from Cuban, Hispaniolan, and Puerto Rican populations appear to have originated by vicariance, founder-events and within-island speciation, while multiple dispersal events (founderevents) between Cuba and Hispaniola during the Middle Miocene and the Late Miocene best explain diversity patterns in the genera Antillattus and Truncattus.