Species: Microdesmus affinis, Olivaceous goby, Short-tail worm-goby

Microdesmus affinis Meek & Hildebrand, 1928

Olivaceous goby, Short-tail worm-goby

Slender, wormlike, body height 3-9% of SL; tail (without fin) 48% of SL; eyes small but not tiny, not skin covered, on side of head; snout and lower jaw with well defined ridges; mouth small, oblique; lower jaw strongly projecting, with small fleshy lump at chin, lips thin, with small side flanges; teeth small, close-set, in 2 rows; gill opening large (not tubular), about length of base of pectoral; dorsal fin spines evenly spaced, 69 elements, origin over rear 1/3 of pectoral; anal II, 41; pectoral 12 rays; pelvics I, 3, shorter than pectorals; tail fin rounded, short; dorsal and anal fins confluent with tail fin; scales small, non-overlapping, well separated; scales with 19 radiating lines; snout and lower jaw scaleless.