''Dahlella'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

leptostraca Leptostraca (from the Greek words for ''thin'' and ''shell'') is an order of small, marine crustaceans. Its members, including the well-studied '' Nebalia'', occur throughout the world's oceans and are usually considered to be filter-feeders. It ...

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

which lives on

hydrothermal vent Hydrothermal vents are fissures on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hot ...

s in the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

. The only species is ''Dahlella caldariensis''.

Description

''Dahlella'' may reach a length of from the base of the

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 ...

to the end of the

abdomen The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...

. Much of the animal is covered by a large, hinged

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 ...

. ''Dahlella'' can be distinguished from other animals in the same family by the presence of a row of denticles (small teeth) on the

eyestalk In anatomy, an eyestalk (sometimes spelled eye stalk and also known as an ommatophore) is a protrusion that extends an eye away from the body, giving the eye a better field of view. It is a common feature in nature and frequently appears in fict ...

s, which it is believed are used to scrape surfaces for food. A similar character is found in '' Paranebalia'' (

Paranebaliidae Paranebaliidae is a family of crustaceans belonging to the order Leptostraca Leptostraca (from the Greek words for ''thin'' and ''shell'') is an order of small, marine crustaceans. Its members, including the well-studied '' Nebalia'', occur th ...

), but the form of the eyestalk is very different in the two taxa.

Distribution

''Dahlella caldariensis'' has been recorded from a small number of sites around

s in the eastern

near the

Galápagos Islands The Galápagos Islands () are an archipelago of volcanic islands in the Eastern Pacific, located around the equator, west of the mainland of South America. They form the Galápagos Province of the Republic of Ecuador, with a population of sli ...

and on the

East Pacific Rise The East Pacific Rise (EPR) is a mid-ocean rise (usually termed an oceanic rise and not a mid-ocean ridge due to its higher rate of spreading that results in less elevation increase and more regular terrain), at a divergent tectonic plate bound ...

. It is one of the deepest-living species of Leptostraca, having been found at depths of over .

Etymology

The generic name ''Dahlella'' commemorates the biologist Erik Dahl of the

University of Lund Lund University () is a public research university in Sweden and one of Northern Europe's oldest universities. The university is located in the city of Lund in the Swedish province of Scania. The university was officially founded in 1666 on the ...

. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

comes from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

word ' meaning

hot bath Hot commonly refers refer to: *Heat, a hot temperature *Pungency, in food, a spicy or hot quality Hot or HOT may also refer to: Places *Hot district, a district of Chiang Mai province, Thailand ** Hot subdistrict, a sub-district of Hot Distric ...

, and is a reference to the natural habitat of ''D. caldariensis''.

References

{{Taxonbar, from1=Q18594975, from2=Q5208882 Leptostraca Monotypic Malacostraca genera Organisms living on hydrothermal vents Animals living on hydrothermal vents Crustaceans described in 1984