Bathydraconidae species have elongate, slender bodies and may be separated from the other notothenioid families by the lack of a spiny first dorsal fin. Their bodies may be stocky, nearly cylindrical or rather depressed at the front and compressed at the rear. There is a single dorsal fin which has a long base and lacks any spines. The anal fin is typically shorter based than the dorsal fin, again having no spines. The pectoral fins are well developed while the pelvic fins contain 1 spine and 5 branched fin rays, beginning to the front of the pectoral fins. The head is moderate to large in size, being depressed in some species. They have a long snout which is flattened or even slightly depressed and is typically short and pointed. They have large mouths which can extend as far as the level of the middle of the eye. The jaws normally have small, conical teeth and occasionally canines, there are usually no teeth elsewhere in the mouth. They have a single external nostril. The operculum may have a rearwards directed hooked or spine, it may be unarmed. The bodies may have scales, typically ctenoid, bony plates or be naked. They can have 1, 2, 3 or 5 lateral lines made up of tubular, pored or pitted scales, and these are occasionally interlinked.[9]
Distribution, habitat and biology
Bathydraconidae species are benthopelagic fishes found in Antarctic waters. They are not fished commercially and little is known about them.[10] The majority of species in this group occur over the continental shelf and slope of Antarctica, but some have been reported from the Antarctic and sub-Antarctic Islands. They inhabit from shallow, inshore waters, although some have been found as deep as 3,000 m (9,800 ft). One species, Gymnodraco acuticeps, has been found in McMurdo Sound living at shallow depths under sea ice, this species may even live under the Ross Ice Shelf.[9]
^N. Derome; W. J. Chen; A. Dettai; C. Bonillo; G. Lecointre (2002). "Phylogeny of Antarctic dragonfishes (Bathydraconidae, Notothenioidei, Teleostei) and related families based on their anatomy and two mitochondrial genes". Mol. Phylogenet. Evol. 24 (1): 139–152. doi:10.1016/S1055-7903(02)00223-3. PMID12128034.