Psychrolutidae

Psychrolutidae
The fish family Psychrolutidae (commonly known as blobfishes, toadfishes, flathead sculpins, tadpole sculpins) contains over 35 recognized species in 8 genera. This family consists of bottom-dwelling marine sculpins shaped like tadpoles, with large heads and bodies that taper back into small, flat tails. The skin is loosely attached and movable, and the layer underneath it is gelatinous. The eyes are placed high on the head, focused forward closer to the tip of the snout. Members of the family generally have large, leaf-like pectoral fins and lack scales, although some species are covered with soft spines. This is important to the species as the depths in which they live are highly pressurized and they are ambush/opportunistic/foraging predators that do not expend energy unless they are forced to.
The blobfish has a short, broad tongue and conical teeth that are slightly recurved and are arranged in bands in irregular rows along the premaxillaries; canines are completely absent. Teeth are nonexistent on the palatines and vomer; which make up the hard palate. The blobfish also has a set of specialized pharyngeal teeth that are well developed and paired evenly along the upper and lower portions of the pharyngeal arch. These specialized teeth may aid in the breakdown of food due to the very strategic dependency on whatever food falls from above.
They are found in the Atlantic and Pacific Ocean. Psychrolutes phrictus have been reported near the Mexican Pacific coast, which extends the southern range by 1,733 km. Myoxocephalus thompsonii, deepwater sculpin, have even been reported in Lake Ontario which were once thought to be extirpated. Psychrolutidae species tend to habituate the northern most region of the Pacific ocean due to lower temperatures, and Indian Oceans. They are found in depths ranging from 300–1,700 meters. The adults live on the sea floor, between deep, The intense biological pressure to conserve energy within deep sea fish seems to be true across many species; most of them are long lived, have a slow rate of reproduction, growth, and aging. In this case the blobfish can live to be roughly 130 years old. Categorized as the predator of the deep sea they have no real predatory issues; a big help to aid in their energy saving. Their diet also helps in their energy saving abilities. They feed on small crustaceans, sea pens, sea worms, and any other small organisms that swim right in front of them. Their name is derived from the Greek psychrolouteo, meaning "to have a cold bath". They tend to live in colder waters, although some range into warm-temperate seas.
The blob sculpin, Psychrolutes phrictus, exhibits complex nesting behaviors complete with egg guarding. Reproductively the blobfish have been seen gathering in large numbers to lay their pinkish eggs in a single surrounding nesting area. The number of eggs laid within one nest can range from 9,000 to 108,000. Another observation of the parental care of the blobfish is that their eggs resemble being cleaned. It is believed that as the female blobfish hover around the nests they also clean them and remove any sand or dirt.
Subfamilies and genera
Psychrolutidae is divided into two subfamilies in the 5th edition of Fishes of the World as follows:
subfamily Cottunculinae Regan, 1913
Ambophthalmos K. L. Jackson & J. S. Nelson, 1998
Cottunculus Collett, 1876
Dasycottus T.H. Bean, 1890
Eurymen Gilbert & Burke, 1912
Malacocottus T.H. Bean, 1890
subfamily Psychrolutinae Günther, 1861
Ebinania Sakamoto, 1932
Gilbertidia Berg, 1898
Neophrynichthys Günther, 1876
Psychrolutes Günther, 1861
Other authorities include many of the genera of marine sculpins from the family Cottidae in the Psychrolutidae, leaving the Cottidae as a largely freshwater family. For example, the Catalog of Fishes classifies the family as follows:
subfamily Psychrolutinae Günther, 1861
Alcichthys Jordan & Starks, 1904
Ambophthalmos Jackson & Nelson, 1998
Andriashevicottus Fedorov, 1990
Antipodocottus Bolin, 1952
Archistes Jordan & Gilbert, 1898
Artediellichthys Fedorov, 1973
Artediellina Taranetz 1941
Artedielloides Soldatov, 1922
Artediellus Jordan, 1885
Ascelichthys Jordan & Gilbert, 1880
Astrocottus Bolin, 1936
Atopocottus Bolin, 1936
Bero Jordan & Starks, 1904
Bolinia Yabe, 1991
Chitonotus Lockington, 1879
Cottiusculus Jordan & Starks, 1904
Cottunculus Collett, 1875
Daruma Jordan & Starks, 1904
Dasycottus T.H. Bean, 1890
Ebinania Sakamoto, 1932
Eurymen Gilbert & Burke, 1912
Gilbertidia Berg, 1898
Leiocottus Girard, 1856
Lepidobero K. J. Qin & X. B. Jin, 1992
Malacocottus T.H. Bean, 1890
Micrenophrys Andriashev, 1954
Neophrynichthys Günther, 1876
Ocynectes Jordan & Starks, 1904
Phallocottus Schultz, 1938
Phasmatocottus Bolin, 1936
Pseudoblennius Temminck & Schlegel, 1850
Psychrolutes Günther, 1861
Radulinopsis Soldatov & Lindberg , 1930
Ricuzenius Jordan & Starks, 1904
Ruscarius Jordan & Starks, 1895
Sigmistes Rutter, 1898
Stelgistrum Jordan & Gilbert, 1898
Synchirus T.H. Bean, 1890
Taurocottus Soldatov & Pavlenko, 1915
Thyriscus Gilbert & Burke, 1912
Trichocottus Soldatov & Pavlenko, 1915
Triglops Reinhardt, 1830
Vellitor Jordan & Starks, 1904
Zesticelus Jordan & Evermann, 1896
subfamily Myoxocephalinae Gill, 1908
Argyrocottus Herzenstein, 1892
Enophrys Swainson, 1839
Megalocottus Gill, 1861
Microcottus Schmidt, 1940
Myoxocephalus Tilesius, 1811
Porocottus Gill, 1859
Taurulus Gratzianov, 1907
subfamily Oligocottinae Hubbs, 1926
Artedius Girard, 1856
Clinocottus Gill, 1861
Furcina Jordan & Starks, 1904
Icelinus Jordan, 1885
Oligocottus Girard 1856
Orthonopias Starks & Mann, 1911
Stlengis Jordan & Starks, 1904
subfamily Icelinae Jordan, 1923
Chitonotus Lockington, 1879
Gymnocanthus Swainson, 1839
Icelus Krøyer, 1845
Rastrinus Jordan & Evermann, 1896
subfamily Radulinae Taranetz, 1941
Asemichthys Gilbert, 1912
Radulinus Gilbert, 1890
References
Glubokov, A.I., Glubokovskii, M.K. & Kovacheva, N.P. New Data on Soft Sculpin Malacocottus zonurus (Psychrolutidae) from the Northwestern Bering Sea. J. Ichthyol. 59, 435–438 (2019). Retrieved 23 March, 2021.
External links
Photo of a Fathead trawled near New Zealand
Cottoidea
Ray-finned fish families