Abstract Detail

Biogeography

Jestrow, Brett [1], Gutiérrez, Jorge [2], Francisco-Ortega, Javier [3].

Islands within Islands: a Radiation across the Serpentine Archipelago of Cuba.

The Caribbean Island Biodiversity Hotspot is the largest insular system of the New World and a priority for biodiversity conservation worldwide. The tribe Adeliae (Euphorbiaceae) has over 35 species endemic to this hotspot, representing one of the most extraordinary cases of speciation in the West Indies, involving taxa from Cuba, Hispaniola, Jamaica, and the Bahamas. These species form a monophyletic group and traditionally have been accommodated in two endemic genera: Lasiocroton and Leucocroton. A study based on: (1) scanning electron microscopy of pollen and trichomes, (2) macromorphology, and (3) molecular data, was conducted to reveal generic relationships within this group. Phylogenies were based on parsimony and Bayesian analyses of nucleotide sequences of the ITS regions of the nuclear ribosomal DNA and the non-coding chloroplast DNA spacers psbM-trnD and ycf6-pcbM. Three major monophyletic assemblages were revealed, one of them was restricted to Hispaniola and was sister to a clade with two monophyletic groups. The first of these two groups was restricted to Cuba and had those species confined to serpentine soils. The second group had species occurring in Cuba, Hispaniola, Jamaica, and the Bahamas. Morphological, biogeographical, and ecological data provided additional support for each of these three monophyletic assemblages. The Hispaniolan taxa were accommodated in a new genus with four species: Garciadelia. Leucocroton had those species from serpentine soils of Cuba, and the rest of the endemic species of the tribe were placed in Lasiocroton. The geographic history of the islands as well as the phylogenetic placement of the Leucocroton-alliance, allows the present study to include both the historical biogeography of the Leucocroton-alliance across the islands of the Caribbean based on a dispersal-vicariance analysis.

Broader Impacts:

1 - Florida International University, Deparment of Biological Sciences, 11200 SW 8th St., Miami, Florida, 33199, USA
2 - Jardín Botánico Nacional, Universidad de la Habana, Carretera del Rocío km 3 1/2, La Habana, Cuba
3 - Florida International Universsity & Fairchild Tropical Botanic Garden, Biological Sciences & Center for Tropical Plant Conservation, Miami, FL, 33199, USA

Keywords:
none specified

Presentation Type: Oral Paper:Papers for Topics
Session: 3
Location: 551A/Convention Center
Date: Monday, August 2nd, 2010
Time: 10:15 AM
Number: 3009
Abstract ID:202