Photocorynus spiniceps Regan 1925

Metamorphosed females distinguished by the following characteristics: have spine on epiotic, pair of spines on postemporal and 5-6 spines on preopercle; frontals meet on midline, each with well-developed anterodorsal spine; moderately strong maxillae, jaws with numerous short teeth arranged in several series; absence of vomerine teeth; presence of first pharyngobranchial; ceratohyal lacking anterodorsal process; posterior margin of hypural plate is entire; extremely short ninth caudal fin ray, length of illicium less than 10%SL; esca nearly sessile on snout, without appendages; absence of hyoid barbell; second and third pectoral radials are subequal; darkly pigmented skin. Free-living juvenile males characterized by: lacking cranial and preopercular spines; preopercle not strongly curved; epiotic region of skull highly elevated; 8-9 teeth on each side of upper and lower jaws, all shorter than the denticular teeth; small denticular bones, placed slightly behind tip of jaws; slender denticular teeth, 3 on upper denticular and 3-4 on lower denticular; slightly tubular eyes, diameter 8-9% SL; moderately enlarged and inflated olfactory organs, nearly as large as eyes; 3 olfactory lamellae; skin unpigmented. Adult males characterized by: having skin that is very faintly pigmented; olfactory organs and to a lesser extent the eyes are degenerated; jaw teeth lost except in the lower jaw of one known specimen (Ref. 86949).

Also mesopelagic. Males dwarfed, becoming parasitic on females (Ref. 10762).