The short-flowered, mesophyllous West Indian species of Exostema were first named E. parviflorum by L. C. Richard (1808), whose brief description, cited by Bonpland, gave only "the Antilles" for the species' locality. Krug and Urban (1899) named E. elegans to distinguish the Hispaniolan element, which differs in leaf shape and texture from most Cuban material. All subsequent authors have recognized the Cuban and Hispaniolan plants as separate species, yet confusion persists concerning the names, delimitation and distributions of these species. These taxonomic difficulties are due to uncertainty over the identity of Richard's type specimen, and to the great morphological variability of the Cuban element. Literature review, herbarium and field studies indicate that: 1) the E. parviflorum Rich. type represents the Hispaniolan species; 2) the name E. valenzuelae A. Rich. (used by Borhidi and Fernández, 1989) was retracted by its author so must be rejected; 3) the Cuban element's first valid name is Solenandra ixoroides Hook. f. (1876), named mistakenly as a new genus due to immature floral material. Accordingly, the new combination E. ixoroides (Hook. f.) T. McDowell is made to designate the Cuban species. Exostema ixoroides exhibits tremendous variability in pubescence and size of stems, leaves, flowers and fruits. Eight segregate Cuban species, named by Krug & Urban, Standley, and Borhidi & Fernández, are here considered to be ecotypic forms and are included in E. ixoroides. Two distinctive xerophyllous species are very closely related to E. ixoroides and E. parviflorum: E. myrtifolium Griseb., endemic to serpentine in N. E. Cuba, and E. selleanum Urb. & Ekman, endemic to rocky limestone in S.E. Cuba and S.W. Hispaniola. These four species, together with the Meso-American E. mexicanum A. Gray and Andean E. corymbosum (Ruiz & Pav.) Spreng., comprise Exostema section Brachyanthum D.C., which includes all the species with short flowers in terminal compound cymes (McDowell 1996). Morphological and DNA based cladistic analyses support an Andean origin for the section, with subsequent migration to Meso-America and ultimate diversification of endemic species in Cuba and Hispaniola.