ABSTRACT
Molluscan biodiversity in the Grenadian and Surinamian Subprovinces Extending from Aruba in the west to Anguilla in the north, and encompassing the coral islands off Venezuela, northern Trinidad, and the Leeward and Windward Islands of the Lesser Antilles, the Grenadian Subprovince (Figure 9.1) is composed entirely of island archipelagos. Within the subprovincial boundaries, ve separate centers of speciation can be differentiated. These include: (1) the Dutch Islands of Aruba, Curaçao, and Bonaire (the ABC Islands); (2) the coralline islands and atolls off Venezuela; (3) the Lesser Antilles Islands from Tobago to Guadeloupe; (4) the Lesser Antilles Islands from Guadeloupe to Anguilla; and (5) the Barbados Seamount. Since most of the island chains, particularly those in the Windward Group, are separated by very deep water channels and trenches, many nonvagile mollusks have become genetically isolated and have undergone speciation or incipient speciation (subspeciation). Several groups of gastropods have evolved endemic species radiations along some of the island chains, with the conid genus Tenorioconus being one of the most prominent and characteristic having evolved at least seven species and subspecies in the area extending from Guadeloupe to Aruba (discussed later in this chapter). The Grenadian Subprovince also contains several endemic genera, including Roquesia (Muricidae; see Appendix 2), Globivasum (Turbinellidae), Aphera (Cancellariidae), and Arubaconus (Conidae; see Appendix 2), and endemic species radiations of the genera Oliva (Americoliva) (Olividae) and Dauciconus (Conidae).
