Common names: specter-goby (English), Gobio-espectro (Espanol)
Akko rossi Van Tassell & Baldwin, 2004
Very elongate; very small eyes; head without pores; vertical and horizontal rows of small papilla on head and operculum; mouth large, almost vertical; upper jaw slightly extendible, ends before center of eye; teeth elongate, large, depressible, lower teeth overlapping the upper jaw when closed; upper jaw with one row of long, well separated canine teeth, lower with two rows, the outer row enlarged; gill opening from a little below top of pectoral base to a little above pelvic base, lower rear edge curved back; gill arches with simple to complex papillae rather than rakers; dorsal, anal and tail fins with serially branched rays; dorsal fins connected, VII, 15; anal fin I, 15; dorsal and anal fins joined to tail fin; pectoral fins short; pelvics fused in a deeply cupped, circular disc on a stalk, fin rays multiply branched; scales small, rounded, smooth, imbedded, not overlapping; head and pectoral base scaleless; no lateral line.
Body translucent, paler below; speckled with black on upper half of head and body; all fins black except the pelvics.
Size: 12 cm.
Habitat: mud bottoms, estuaries.
Depth: 5-10 m.
Known only from the Gulf of Fonseca, El Salvador.