Phylogeography, Generic Allies, and Nomenclature of Caribbean Endemic Genus Neolaugeria (Rubiaceae) Based on Internal Transcribed Spacer Sequences

Neolaugeria (Rubiaceae) comprises three species of woody shrubs and trees that are endemic to the West Indies. A molecular phylogeny was constructed using nucleotide sequences of the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA to elucidate the evolutionary history of the genus. The data support the monophyly of Neolaugeria and a relatively distant relationship to Stenostomum, a genus that Neolaugeria has variously been merged into as a section. Constraint analyses indicate that Neolaugeria resinosa may occupy a more basal position, supporting a pattern of speciation and colonization in a northwesterly direction from the Lesser Antilles to the Greater Antilles and the Bahamas.