| Rhincalanus nasutus | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Copepoda |
| Order: | Calanoida |
| Family: | Rhincalanidae |
| Genus: | Rhincalanus |
| Species: | R. nasutus |
| Binomial name | |
| Rhincalanus nasutus Giesbrecht, 1888 | |
Rhincalanus nasutus is a copepod in the family Rhincalanidae.
Rhincalanus nasutus is a species complex, composed of at least two cryptic species: one species consisting of, at the very least, individuals off of Peru, in the Sulu Sea, and in the California Current, in addition to another species composed of specimens from the Kuroshio Current, the southwest Pacific, and the northern Atlantic. In its genus, it is sister to R. gigas . [1]
The female of R. nasutus ranges anywhere from about 2.8 to 6.1 millimetres (0.11 to 0.24 in) in length, and the male is generally between about 2.7 and 4.5 millimetres (0.11 and 0.18 in). [2]
Rhincalanus nasutus is found in waters across the globe, [2] primarily in the open ocean [3] and continental shelf and slope waters. [4]
Rhincalanus nasutus is seasonal in terms of the timing of reproduction. Off of the waters of southern California, it generally reproduces from February to April, and it also can reproduce in late summer, as late as June. This reproduction is likely to be limited by food, as evidenced by this copepod failing to breed in the absence of food. [5] Copepodite stages I through IV are usually found in the surface waters (from sea level to 200 metres (660 ft) in depth). The abundance of individuals in the surface, however, varies seasonally: they are most abundant during the spring, and are not present during summer and autumn. Stage V copepodites and adults are generally distributed below 200 metres (660 ft) in depth, and especially below 500 metres (1,600 ft). [6] In seasonal waters, such as the Gulf of Aqaba, stage V copepodites go into diapause to moult into females. During this time, they also rapidly accumulate wax esters, possibly for future reproduction. [3]
Meroplankton are a wide variety of aquatic organisms which have both planktonic and benthic stages in their life cycles. Much of the meroplankton consists of larval stages of larger organism. Meroplankton can be contrasted with holoplankton, which are planktonic organisms that stay in the pelagic zone as plankton throughout their entire life cycle.
Thysanoessa is a genus of the krill that play critical roles in the marine food web. They're abundant in Arctic and Antarctic areas, feeding on zooplankton and detritus to obtain energy. Thysanoessa are responsible for the transportation of carbon and nutrients from surface waters to deeper trophic levels. This genus serves as prey for various fish and provide energy to marine ecosystems as they are at a low trophic level. Most travel through vertical migration, meaning they travel up and down in the water column, providing food for predators at the surface during the night, and at deeper levels during the day.
Diel vertical migration (DVM), also known as diurnal vertical migration, is a pattern of movement used by some organisms, such as copepods, living in the ocean and in lakes. The word "diel" comes from Latin: diēs, lit. 'day', and means a 24-hour period. The migration occurs when organisms move up to the uppermost layer of the sea at night and return to the bottom of the daylight zone of the oceans or to the dense, bottom layer of lakes during the day. It is important to the functioning of deep-sea food webs and the biologically driven sequestration of carbon.
Oxyrrhis is a genus of heterotrophic dinoflagellate, the only genus in the family Oxyrrhinaceae. It inhabits a range of marine environments worldwide and is important in the food web dynamics of these ecosystems. It has the potential to be considered a model organism for the study of other protists. Oxyrrhis is an early-branching lineage and has long been described in literature as a monospecific genus, containing only Oxyrrhis marina. Some recent molecular phylogenetic studies argue that Oxyrrhis comprises O. marina and O. maritima as distinct species, while other publications state that the two are genetically diverse lineages of the same species. The genus has previously been suggested to contain O. parasitica as a separate species, however the current consensus appears to exclude this, with Oxyrrhis being monospecific and containing O. marina and O. maritima as separate lineages of the type species. The genus is characterised by its elongated body which is anteriorly prolonged to a point, its complex flagellar apparatuses which attach to the ventral side of the cell, and the unique features of its nucleus.
Calanus hyperboreus is a copepod found in the Arctic and northern Atlantic. It occurs from the surface to depths of 5,000 metres (16,000 ft).
Calanus propinquus is a copepod found in Antarctica, and the surrounding waters.
Calanoides acutus is a copepod found in Antarctica and the surrounding waters.
Metridia longa is a copepod found in the Arctic, the north Atlantic, the Pacific, and surrounding waters. The female has an average length of about 4.2 millimetres (0.17 in), and the males have an average length of about 3.5 millimetres (0.14 in).
Neocalanus plumchrus is a large species of copepod found in the Pacific and Arctic Oceans. It was described in 1921 H. by Marukawa. N. flemingeri was formerly considered as conspecific, likely as a form, until it was split in 1988 by Charles B. Miller.
Neocalanus cristatus is a species of copepod found primarily in the northern Pacific.
Metridia pacifica is a copepod found in the north Pacific and surrounding waters.
Eucalanus bungii is a copepod found in the north Pacific and surrounding waters.
Pseudocalanus newmani is a copepod found in Arctic and northern Pacific waters. It was described by Frost in 1989. It is found in the Arctic and surrounding waters. There are multiple generations. Unlike some copepods, P. newmani undergoes reverse diel vertical migration, descending during the night, and ascending during the day, although it may undergo normal or no migration at all depending on predation. This copepod is primarily herbivorous.
Calanus sinicus is a copepod found in the northwest Pacific.
Rhincalanus gigas is a large Antarctic copepod.
Temora stylifera is a copepod primarily found in the Atlantic and surrounding waters.
Pseudocalanus elongatus is a copepod found primarily in the Atlantic Ocean.
The lipid pump sequesters carbon from the ocean's surface to deeper waters via lipids associated with overwintering vertically migratory zooplankton. Lipids are a class of hydrocarbon rich, nitrogen and phosphorus deficient compounds essential for cellular structures. This lipid carbon enters the deep ocean as carbon dioxide produced by respiration of lipid reserves and as organic matter from the mortality of zooplankton.
Metridia gerlachei is a copepod found primarily in Antarctic and sub-Antarctic waters.
Pseudocalanus minutus is a small copepod found in the Arctic Ocean and surrounding waters.