Jellynose fish

Fish World | Jellynose fish | The Jellynose fish or tadpole fish, the small order Ateleopodiformes. This group of ray-finned fish is monotypic with a single family Ateleopodidae. It has about a dozen species in four genera, but these enigmatic fishes in need of taxonomic revision.
The scientific name means "Ateleopus-shaped", from Ateleopus (type genus) + standard fish order suffix "-formes". Jellynoses its deep water, bottom-dwelling marine fish. They are known from the Caribbean Sea, eastern Atlantic, western and central Indo-Pacific and the Pacific coast of Central America.

Their skeletons are largely cartilage (hence "jelly nose"), although they are true teleosts and not related to Chondrichthyes. The heads are large, with a bulbous nose, and (usually) elongated body tapers towards the tail. Their tail fins are very small, and except Guentherus it is merged with the long anal fin (which has 70 rays or more). The ventral fins of young people to have 10 rays, but in adults is reduced to a single elongated jet at the throat.
Again, Guentherus is an exception, while retaining some fins and pelvic fins as adults, who are behind (not under) the pectoral fins. Dorsal fins often high, with a relatively short base (9-13 rays, but some as little as 3), they are placed just behind the head. They have seven branchiostegal rays. The species have a range of sizes, the longest reach 2 m (6.6 ft).

Most of the species are poorly known, but the Highfin Tadpole Fish (Guentherus altivelis) is of potential interest for commercial fishing.

Together with their family, Stomiiformes, the jellynoses often placed in the teleost super Stenopterygii order. Whether it was justified to accept such a small group, the question may well be that the closest living relatives of the "Stenopterygii" are found among the super Protacanthopterygii order, and that the first should be merged into the latter. In some classifications, the "Stenopterygii" aside, but when Protacanthopterygii and monotypic super Cyclosquamata order in unranked clade called Euteleostei. That probably would split two additional orders from the monotypic super Protacanthopterygii, and is probably not ideal because of the abundance of very small taxa would create. In fact, in some treatments, the nose jelly fish, even put in another super monotypic order, Ateleopodomorpha.

The Ateleopodidae are also placed in the Lampriformes Myctophiformes or which otherwise are extra super orders. The relationships of these taxa to the above is still not solved at all, and whether they are called or Euteleostei Protacanthopterygii sensu lato, the phylogeny of this group of moderately advanced Teleostei is a need for further research.

Scientific classification
Kingdom: Animalia
Tribe: Chordata
Subphylum: Vertebrata
Division: Neopterygii
Infra Class: Teleostei
Super Order: Stenopterygii (disputed)
Order: Ateleopodiformes
Family: Ateleopodidae