Abstract

Rovers, rubyfishes, and bonnetmouths (Emmelichthyidae) comprise a small family of fishes that can be distinguished from other perch-like fishes by their generally red, fusiform bodies, highly protrusible mouths, and large rostral cartilage. Their highly protrusible upper jaws have led ichthyologists to group morphologically similar but distantly related taxa within the Emmelichthyidae and is one of the stunning examples of morphological convergence within perch-like fishes. In 2014, the first and only emmelichthyid from the Red Sea, Emmelichthys marisrubri, was described. This species is diagnosed by 80–83 lateral-line scales, 8 dorsal-fin rays, and 4–5 isolated dorsal spines that are separated from membrane-bound dorsal-fin elements, among other features. While examining the osteology of E. marisrubri, I discovered several differences in the oral jaws, suspensorium, neurocranium, and dorsal fin when compared to other species of rovers. Based on these differences and the results of a phylogenetic analysis, I transfer this taxon to the genus Dipterygonotus within the Lutjanidae and among the fusiliers (formerly Caesionidae), an Indo-Pacific group of fishes that also have highly protrusible upper jaws.