Genus: Trichiurus, Cutlassfishes, Hairtails
body a long, compressed ribbon
D: low, very long base
tail slender, pointed, no C
lower jaw projecting
A = tiny, imbedded spines
Very elongate, strongly compressed, ribbon-like, tapering to slender, pointed hair-like tail; long snout; large eye; a large mouth with protruding lower jaw with large fangs; lower edge of gill cover concave; dorsal and anal fins are extremely long-based and low; dorsal fin origin over gill cover, with very long base, III, 115-135, no notch between spines and rays; anal fin inconspicuous, 95-115 minute spines mostly buried in skin; pectoral fins pointed up, I, 11; no pelvic fins; without tail fin; lateral line complete; no scales.
A genus found worldwide in tropical and temperate areas; contains 9 species; with one circumglobal tropical to subtropical species found in our region.