''Boreomysis'' (from Greek ''
Boreas'', the god of the northern winds, and the genus name ''
Mysis'') is a
mysid crustacean genus, the type of the subfamily
Boreomysinae
Boreomysinae is a subfamily of large, mostly deep-water oceanic mysid crustaceans from the family Mysidae. The name, which can be translated as "northern mysids", comes from the genus '' Boreomysis'' G.O. Sars, 1869, established for '' Boreomys ...
of the family
Mysidae
Mysidae is the largest family of crustaceans in the order Mysida, with over 1000 species in around 170 genera.
Characteristics
Members of the family Mysidae are distinguished from other mysids by the fact that the first pereopod (walking leg) h ...
. Majority of the species are found in the ocean deep water. Cosmopolitan. 38 species.
Description
Compared to another genus of the subfamily, ''
Neobirsteiniamysis'', the members of the genus ''Boreomysis'' have narrower
telson
The telson () is the hindmost division of the body of an arthropod. Depending on the definition, the telson is either considered to be the final segment (biology), segment of the arthropod body, or an additional division that is not a true segm ...
, not expanded in the central part, being always narrower than in the anterior part. Also the eyes are mostly normally developed. Although in certain species the eyes may be reduced to certain extent, they still always possess
cornea
The cornea is the transparency (optics), transparent front part of the eyeball which covers the Iris (anatomy), iris, pupil, and Anterior chamber of eyeball, anterior chamber. Along with the anterior chamber and Lens (anatomy), lens, the cornea ...
, unlike in ''
Neobirsteiniamysis''.
[
]
Taxonomy
The originally designated type species is '' Mysis arctica'' Krøyer, 1861.[
''Boreomysis'' is one of the most difficult mysid genera, mostly due to considerable variation with age.]
Classification
The species of ''Boreomysis'' are distributed among two subgenera:
*''Boreomysis'' sensu stricto, 34 species, and
*''Petryashovia'' Daneliya, 2023, 4 species
Subgenus ''Boreomysis'' sensu stricto
The nominate subgenus combines most of the species of ''Boreomysis'' sensu lato, found in epi-bathypelagic waters, which have pointed rostrum
Rostrum may refer to:
* Any kind of a platform for a speaker:
**dais
**pulpit
** podium
* Rostrum (anatomy), a beak, or anatomical structure resembling a beak, as in the mouthparts of many sucking insects
* Rostrum (ship), a form of bow on naval ...
and large ventrolateral projections of the carapace
A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the unde ...
. Nearly all its species have 2-segmented propodus of pereopods (the exception is '' Boreomysis dubia'', which has only one segment).[
]
Subgenus ''Petryashovia''
Subgenus ''Petryashovia'', with the type species '' Boreomysis megalops'' G. O. Sars, 1872, includes epi-mesopelagic species with somewhat less developed carapace projections (no rostrum and rather short ventrolateral lobes) and undevided propodus of pereopods.
The name is dedicated to a carcinologist
This is a list of notable carcinologists. A carcinologist is a scientist who studies crustaceans or is otherwise involved in carcinology (the science of crustaceans).
References
{{Reflist, 24em
Carcinologists, .
Lists of zoologists, Carcino ...
Victor Vladimirovich Petryashov (1956–2018).[
]
Distribution
Members of the genus are found in all oceans, and ''Boreomysis'' can be considered cosmopolitan.[
]
Habitat
Most of the species are oceanic deep-water. Some, however, penetrate deep parts of inland seas. The depth is from surface or subsurface waters (epipelagic
The photic zone (or euphotic zone, epipelagic zone, or sunlight zone) is the uppermost layer of a body of water that receives sunlight, allowing phytoplankton to perform photosynthesis. It undergoes a series of physical, chemical, and biological ...
) down to 6000 m (bathypelagic
The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of below the ocean surface. It lies between the mesopelagic above and the abyssopelagic below. The bathypela ...
).[
]
References
{{Taxonbar, from=Q10433080
Mysida
Malacostraca genera