| Family | Scientific Name | Author | Year | Common Name |
| Bythitidae | Thalassobathia pelagica | Cohen | 1963 | Pelagic Brotula |
Family Bythitidae — Scales present in all but a few species; skin firm. Precaudal vertebrae 9-22. Swim bladder present. Developed rakers on anterior arch fewer than 6 in most species but in some as many as 18. No median basibranchiall tooth patch. Pelvic fin with a single ray or absent in a few.
Thalassobathia pelagica
Unique Characters: Pelagic Brotula Thalassobathia pelagica. Pelvic fin with 2 short, fleshy rays in each. Anterior nostril non-tubular and placed high in snout; maxilla narrow posteriorly. Gill rakers on first arch reduced to a few small fleshy flap and protruberances. Skin thick; scales absent for head and absent or scattered on body. In association with scyphomedusan Stygiomedusa gigantea jellyfish.
Similar Species:
Black Brotula Stygnobrotula latebricola
Twospine Brotula Diplacanthopoma brachysoma
Fivepore Brotula
Bythites gerdae
Black Brotula Stygnobrotula latebricola. Body brownish black to black. Fins black. Head and body notably compresses; snout blunt. Snout equals diameter of eye. Pelvic fins absent or with a single filamentous ray in each Palatine teeth absent.
Twospine Brotula Diplacanthopoma brachysoma. Prominent skin flap bearing large pore above the upper angle of the opercle. Body tapers to a slender tail. Pelvic fins absent or with a single filamentous ray in each Palatine teeth present. Scales absent from head and bases or dorsal and anal fins.
Fivepore Brotula Bythites gerdae. Pelvic fins absent or with a single filamentous ray in each. Palatine teeth present. No prominent skin flap with pore above opercle. Head without scales. Upper jaws end well behind eye. Opercular spine strong.
Reference:
FAO. 1999. Species catalogue. Volume 18. Ophidiiform fishes of the world (Order Ophidiiformes). An annotated and illustrated catalogue of pearlfishes, cusk-eels, brotulas and other ophidiiform fishes known to date. FAO Fisheries Synopsis. No. 125, Vol. 18. 178p., 136 figs. Rome, Italy.
Gallery