''Eptatretus springeri'', the Gulf hagfish, is a bathy

demersal The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of ...

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...

which lives primarily in the northeastern

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of ...

. It has been observed feeding at and around brine pools: areas of high

salinity Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal ...

which resemble

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

s on the

ocean floor The seabed (also known as the seafloor, sea floor, ocean floor, and ocean bottom) is the bottom of the ocean. All floors of the ocean are known as 'seabeds'. The structure of the seabed of the global ocean is governed by plate tectonics. Most of ...

that do not mix with the surrounding water due to difference in

density Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematical ...

. The high salt content, approximately 200 ppt compared to 35 ppt for standard

seawater Seawater, or salt water, is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% (35 g/L, 35 ppt, 600 mM). This means that every kilogram (roughly one liter by volume) of seawater has appro ...

, creates a

buoyant Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the pr ...

surface which renders oceanic

submersible A submersible is a small watercraft designed to operate underwater. The term "submersible" is often used to differentiate from other underwater vessels known as submarines, in that a submarine is a fully self-sufficient craft, capable of ind ...

s unable to descend into the pool. It is believed that the inside of the pools only supports

microbial A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...

life, while the majority of macroscopic life, such as methane-utilizing mussels, exists on the edges.S. E. MacAvoy, E. Morgan, R. S. Carney, and S. A. Macko, "Chemoautotrophic Production Incorporated by Heterotrophs in Gulf of Mexico Hydrocarbon Seeps: An Examination of Mobile Benthic Predators and Seep Residents," Journal of Shellfish Research 27(1), 153-161, (1 March 2008). https://doi.org/10.2983/0730-8000(2008)27 53:CPIBHI.0.CO;2 The Gulf hagfish feeds on the

primary producers An autotroph or primary producer is an organism that produces complex organic compounds (such as carbohydrates, fats, and proteins) using carbon from simple substances such as carbon dioxide,Morris, J. et al. (2019). "Biology: How Life Works", ...

of these environments, as well as other

predators Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...

. Like other species of hagfish, the Gulf hagfish produces

slime Slime may refer to: Biology * Slime mold, a broad term often referring to roughly six groups of Eukaryotes * Biofilm, an aggregate of microorganisms in which cells adhere to each other and/or to a surface * Slimy (fish), also known as the pony ...

from glands in its skin. It also exhibits complex knotting behavior, in which the body of the hagfish is twisted into knots, believed to be related to the removal or management of slime. Hagfish of the genus ''

Eptatretus ''Eptatretus'' is a large genus of hagfish. Species There are currently 49 recognized species in this genus: * ''Eptatretus aceroi'' Polanco Fernández & Fernholm, 2014 (Acero's hagfish)Polanco Fernandez, A. & Fernholm, B. (2014): A New Specie ...

'' (including ''E.springeri'' and the more extensively studied '' E. stoutii''), are able to form more complex knots than those of genus ''

Myxine ''Myxine'' is a genus of hagfish, from the Greek μυξῖνος (''myxinos'', "slimy"). In 2021, three new species of ''Myxine'' were described from the Galápagos including '' M. phantasma'', the only species of ''Myxine'' to not have melan ...

'' due to the

anisotropic Anisotropy () is the property of a material which allows it to change or assume different properties in different directions, as opposed to isotropy. It can be defined as a difference, when measured along different axes, in a material's physic ...

nature of their skin.

References

* ;Specific

External links

* Fish described in 1952 Fish of the Gulf of Mexico Myxinidae {{jawless-fish-stub

See also

References

External links