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Description: Body somewhat thick, very long and narrow with a small head and round medium-sized eye and mouth with a blunt, hooked, and protruding lower jaw. Pectoral fins short and pelvic fins separate and short. Dorsal and anal fin bases very long, caudal peduncle very short and relatively wide. The caudal fin has a distinct vertical row and three lateral rows of caudal fin neuromasts (sensory papillae) and there are 5-7 procurrent caudal fin rays (5-6 spindly). Very lightly marked, mostly along the ventral midline: a melanophore at the pelvic fin base (often missing), followed by a pair of short rows of melanophores diverging from the pelvic fin base along the side of the abdominal gut strip. There is a row of melanophores along the base of the anal fin rays after the first three (paired and one per ray), becoming more disassociated from the anal fin base and more variable in number and depth at the last several rays and continuing into the ventral caudal peduncle ending at the start of the lower procurrent caudal fin rays. A few scattered melanophores sometimes extend out along the lower segmented caudal fin rays. A rare individual has a surface melanophore on the lateral aspect of the caudal peduncle (a characteristic of larval Microdesmus spp.), although it is off-center from the lateral midline. Dorsal markings consist of a few off-center and variably-paired melanophores at the base of some posterior dorsal fin rays continuing onto the dorsal caudal peduncle ending at the start of the upper procurrent caudal fin rays. Some larvae have a melanophore at the angle of the jaw. Internal melanophores occur around the saccule and along the dorsal surface of the swim bladder (not at the vent).