Distribution:
Circumglobal.
Habitat:
Deep sea.
Remarks:
The ceratiid sea devils are the most widespread family of deep sea anglerfishes, and are found in all oceans. The family name Ceratiidae comes from the Greek keras, or "horn," which refers to these fishes' bioluminescent lure. This lure is a fleshy appendage (esca) at the end of an elongate dorsal spine (illicium), used for attracting prey.
Like most deep sea fishes, members of the family Ceratiidae are dark in color, with large mouths, small eyes, and no pelvic fins. The cleft of the mouth is vertical to strongly oblique. And there are low fleshy appendages, called caruncles, present before the soft dorsal fin in females.
It is difficult to recognize the male and female sea devils as members of the same species. The much larger females act as a host to the tiny parasitic males. Immature males are free-living, reaching lengths of only several centimeters. However, once mature, they use their sharp, beak-like jaws to bite onto the flanks of the female. They secrete a chemical to fuse themselves to the female's body, and from then onward, live parasitically attached. The organs of the male degenerate, and the circulatory system becomes continuous, rendering the males little more than gonads to supply sperm as needed. Females may be found with multiple males attached.
The maximum length in this family is achieved in the species Ceratias holboelli, reaching 1.2 m SL.
This family comprises 2 genera, Ceratias and Cryptopsaras, and 4 species.
References:
Nelson 2006