Elacatinus

[[Genus Elacatinus]]

The western North Atlantic coral reef fishes of the genus Elacatinus generally live associated with stony corals or sponges. Böhlke and Robins (1968) published the first review of the group, describing 9 new species, in addition to 3 previously known, for a total of 12 recognized species. While they reduced Elacatinus to a subgenus of Gobiosoma, Eschmeyer and Bailey (1990) assigned generic status to Elacatinus and I follow their designation. Sazima et al. (1996) described a thirteenth species, Elacatinus figaro, from Brazilian waters.

In addition to their specialist associations, each species has a limited geographic range across the western Atlantic reef tract. Within nominal species there is often consistent geographic variation in the color of the lateral body stripe or head markings without other apparent morphological differences (Colin, 1975). These populations are considered color forms of a single morphologically identifiable species with each color form having its own distinct geographic distribution within the total range of the species. It is usually impossible to distinguish between color forms once preserved (Colin, 1975; Böhlke and Robins, 1968).