A New Species of Lythrypnus (Pisces: Gobiidae) from the Tropical Western Atlantic

A new species of fish of the family Gobiidae, Lythrypnus minimus, is described based on material collected in coralline areas of the Colombian Caribbean. The species had been collected previously in the Bahamas, but confused with L. elasson. It is distinguished from its congeners from the Atlantic principally by its tiny size, low scale counts, and pigmentation. Marked sexual dimorphism in coloration and length of the dorsal filament, as well as wide variability in pigmentation, make identification difficult. L. minimus is the smallest species of the genus and one of the smallest vertebrates known. The archipelagos of Rosario and San Bernardo are the only places where important populations of the species are known.