The beetle fauna of Dominica, Lesser Antilles (Insecta: Coleoptera): Diversity and distribution

Abstract

The beetle fauna of the island of Dominica is summarized. It is presently known to contain 269 genera, and 361 species (in 42 families), of which 347 are named at a species level. Of these, 62 species are endemic to the island. The other naturally occurring species number 262, and another 23 species are of such wide distribution that they have probably been accidentally introduced and distributed, at least in part, by human activities. Undoubtedly, the actual numbers of species on Dominica are many times higher than now reported. This highlights the poor level of knowledge of the beetles of Dominica and the Lesser Antilles in general. Of the species known to occur elsewhere, the largest numbers are shared with neighboring Guadeloupe (201), and then with South America (126), Puerto Rico (113), Cuba (107), and Mexico-Central America (108). The Antillean island chain probably represents the main avenue of natural overwater dispersal via intermediate stepping-stone islands. The distributional patterns of the species shared with Dominica and elsewhere in the Caribbean suggest stages in a dynamic taxon cycle of species origin, range expansion, distribution contraction, and re-speciation.