Comprehensive DescriptionRead full entry
The body of metamorphosed females is short, its depth at the base of the pectoral fin 55–70% SL. The length of the head is 50–60% SL. The sphenotics, frontals, and preopercles all bear strong prominent spines. The preopercular spine is compressed, its distal one-half normally divided into 2–5 short broad cusps (in one specimen the spine is undivided on the left side), the upper- and lowermost spine more-or-less strongly curved. The lower jaw bears a symphysial spine. The ventral edge of the articulars is straight.
The nostrils of females are set on elongate papilla. The lateral-line organs are stalked and unpigmented. The pterygiophore of the illicium is short, completely embedded in the skin of the head. The escal bulb is sessile and spherical or distally flattened, with a diameter of about 10% SL, and completely unpigmented except for the inner wall of the photophores. There is a single short posterior escal appendage, divided distally into 2–6 short branches, simple in some juveniles.
The teeth of females are slender, recurved, and depressible, the longest about 5% SL. There are 50–80 teeth on each side of the upper and lower jaws in 40–60 mm specimens, arranged in several diagonal series, 6 to at least 10 oblique longitudinal series, and a greater number of oblique transverse series, increasing with the size of specimens.
The skin of females is totally unpigmented, the peritoneum black. Secondary subdermal pigmentation spreads posteriorly with increasing size of specimens from an anterior concentration on the dorsal surface of the trunk. It also spreads anteriorly from the base of the caudal fin, gradually obscuring the pattern of larval melanophores, and completely covering the body musculature of adults, except for the myosepta. The skin of free-living and parasitic males is also unpigmented.
The body of free-living and parasitic males is elongate. The roof of the skull is not strongly arched. Sphenotic spines are absent or represented only by a small blunt knob. The dorsal contour of the body is straight to slightly convex. The teeth are recurved and depressible. There are 20–24 on each side of the upper and lower jaws, arranged in four very distinct oblique longitudinal series, each with the length of teeth increasing posteriorly. The longest teeth are 3–4% SL and 2–4 times the length of the denticular teeth. Some jaw teeth are lost in larger parasitic males.
The eyes of males are directed anteriorly; they are slightly tubular, with diameters of 6–7% SL. The olfactory organs are situated on the sides of the blunt snout, well separated from the eyes and inflated, their greatest diameter about 6% SL. The anterior nostrils are directed anteriorly, about one-half the size of the posterior nostrils. The olfactory organs and eyes are degenerated in the largest parasitic males.
The skin of free-living and parasitic males is unpigmented. Subdermal pigment is present on the peritoneum and in two series of melanophores along the sides of the body: a dorsal series frequently consisting of a single row of melanophores, but sometimes two or three melanophores in width; and a ventral series of melanophores two to several melanophores in width. The dorsal and ventral series fuse to form a single group of melanophores at the base of the caudal fin.
The body shape and patterns of jaw-teeth and subdermal pigmentation of the larvae are as described for free-living males. The numbers of teeth and melanophores increase with the size of specimens. Except for metamorphic stages, the larvae are inseparable from those of the Linophryne subgenus Rhizophryne.
Fin-ray counts are shared by females and males: the dorsal and anal fins each contain 3 rays, the pectoral-fin 15 or 16 rays. The caudal-fin contains 9 rays, the ninth ray about one-half the length of the eighth.
Females reach a maximum known length of 159 mm (NMNZ P.21248); free-living males, 16 mm (MCZ 32308); and parasitic males, 15 mm (AMS I.21365-8).