Biofluorescence as a tool to resolve crypsis in two bonefish species, Albula goreensis and Albula vulpes, with comments on other external morphology.

Abstract

Bonefish Albula spp. in the Western Atlantic have historically been morphometrically and phenotypically indiscernible. We used biofluorescence in two sympatric, cryptic bonefish species, Albula goreensis and Albula vulpes, to develop a rapid and inexpensive in situ survey for species identification that can be used by managers and recreational anglers. Under ultraviolet (379-387 nm) and royal blue (440-457 nm) lights, the two species expressed differing biofluorescence on the iris, axil of the pectoral fins, the vent and the axil of the pelvic fins. Green biofluorescent patterns were most easily discernible under royal blue light while viewing through a Tiffen Yellow #12 longpass filter, although the use of an ultraviolet light with no visual filter was the most cost-effective. We recommend the adoption of biofluorescent field surveys for bonefish using ultraviolet light on the axil of the pectoral fins and the vent for managers and anglers to differentiate A. goreensis and A. vulpes in real time. The application of this survey will allow for both fisheries' independent and dependent data to be appropriately attributed at the species level, allowing for more effective management of the economically important western Atlantic bonefish fishery.