A preliminary phylogeny of Caribbean Tabebuia based on the nrDNA ITS region

Abstract

Tabebuia Gomes ex DC. (Bignoniaceae) is an extremely diverse Neotropical genus of woody species with great economical value and wide distribution from Mexico to Argentina. Although ca 108 taxa have been described (Gentry, 1992), approximately 61 are distributed throughout the Caribbean with 88% endemicity to the region (Figure 1). The genus also exhibits great versatility in morphological variation (e.g., flower color, uni-foliolateto multi-foliolate), as well as adaptations to a wide range of ecological conditions (e.g., from cloud forest to arid zones, diverse geology, and high to low altitudes). However, the evolutionary relationships of the Caribbean species has still not been elucidated. The purpose of the study is to test the monophyly of the Caribbean group and evaluate the evolutionary relationships. In addition, the gathered information will help evaluate patterns of morphological evolution, adaptive-ecological diversification, as well as biogeographical patterns.