| Urothoe marina | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Malacostraca |
| Superorder: | Peracarida |
| Order: | Amphipoda |
| Family: | Urothoidae |
| Genus: | Urothoe |
| Species: | U. marina |
| Binomial name | |
| Urothoe marina | |
| Synonyms [1] | |
| |
Urothoe marina is a species of small marine amphipod crustaceans in the family Urothoidae. It is found on and burrowing in coarse sediments in shallow coastal waters off northwestern Europe.
Urothoe marina is about 8 millimetres (0.3 in) long, crescent-shaped and a yellowish-white colour. It is laterally compressed and normally lies on one side. The head is fused with the thorax and bears two unequal sized antennae. In the male, the lower antenna is as long as the body but in the female, it is only just longer than the upper one. The upper antenna has a short side branch. [2] The stalked eyes are black. Those of the male are very large while the female has smaller, oval eyes. The thorax consists of eight somites each with its own appendages and some setae. The posterior pereiopods are wider than they are long and have feathery setae. The uropods are densely hairy and the short telson has a single spine and a few setae. [3]
Urothoe marina occurs off the coasts of northwest Europe. Its range includes the North Sea, the English Channel and the Atlantic Ocean from the Shetland Isles southwards to the Bay of Biscay. It is usually found in the neritic zone and at depths of down to 200 metres (660 ft). [3]
Urothoe marina becomes sexually mature at about five months old and may live for a year. The sexes are distinct and breeding takes place between April and October. Fertilisation is internal and there are about fifteen eggs, with batches produced every fifteen days or so. The eggs are brooded rather than being liberated into the water column and the juveniles grow rapidly. Biological dispersal of this species is very limited. [4]
The back three legs of U. marina have flattened joints and are used for digging and it can quickly disappear into the substrate. [2] It is often found in association with the sea potato ( Echinocardium cordatum ), making use of its burrow as a refuge. [5] It also found in association with members of the sea cucumber family, Synaptidae. [3]
Malacostraca is the second largest of the six classes of pancrustaceans just behind hexapods, containing about 40,000 living species, divided among 16 orders. Its members, the malacostracans, display a great diversity of body forms and include crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, amphipods, mantis shrimp, tongue-eating lice and many other less familiar animals. They are abundant in all marine environments and have colonised freshwater and terrestrial habitats. They are segmented animals, united by a common body plan comprising 20 body segments, and divided into a head, thorax, and abdomen.
Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from 1 to 340 millimetres and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far described. They are mostly marine animals, but are found in almost all aquatic environments. Some 1,900 species live in fresh water, and the order also includes the terrestrial sandhoppers such as Talitrus saltator and Arcitalitrus sylvaticus.
Mysida is an order of small, shrimp-like crustaceans in the malacostracan superorder Peracarida. Their common name opossum shrimps stems from the presence of a brood pouch or "marsupium" in females. The fact that the larvae are reared in this pouch and are not free-swimming characterises the order. The mysid's head bears a pair of stalked eyes and two pairs of antennae. The thorax consists of eight segments each bearing branching limbs, the whole concealed beneath a protective carapace and the abdomen has six segments and usually further small limbs.
Ostracods, or ostracodes, are a class of the Crustacea, sometimes known as seed shrimp. Some 33,000 species have been identified, grouped into 7 valid orders. They are small crustaceans, typically around 1 mm (0.04 in) in size, but varying from 0.2 to 30 mm in the case of the marine Gigantocypris. The largest known freshwater species is Megalocypris princeps, which reach 8mm in length. In most cases, their bodies are flattened from side to side and protected by a bivalve-like valve or "shell" made of chitin, and often calcium carbonate. The family Entocytheridae and many planktonic forms do not have calcium carbonate. The hinge of the two valves is in the upper (dorsal) region of the body. Ostracods are grouped together based on shell and soft part morphology. While early work indicated the group may not be monophyletic and early molecular phylogeny was ambiguous on this front, recent combined analyses of molecular and morphological data suggested monophyly in analyses with broadest taxon sampling, but this monophyly had no or very little support. They have a wide range of diets, and the class includes carnivores, herbivores, scavengers and filter feeders, but most ostracods are deposit feeders.
Isopoda is an order of crustacean, which includes woodlice and their relatives. Members of this group are called Isopods and include both terrestrial and aquatic species. All have rigid, segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs on the thorax, and five pairs of branching appendages on the abdomen that are used in respiration. Females brood their young in a pouch under their thorax.
Squat lobsters are dorsoventrally flattened crustaceans with long tails held curled beneath the cephalothorax. They are found in the two superfamilies Galatheoidea and Chirostyloidea, which form part of the decapod infraorder Anomura, alongside groups including the hermit crabs and mole crabs. They are distributed worldwide in the oceans, and occur from near the surface to deep sea hydrothermal vents, with one species occupying caves above sea level. More than 900 species have been described, in around 60 genera. Some species form dense aggregations, either on the sea floor or in the water column, and a small number are commercially fished.
Nephrops norvegicus, known variously as the Norway lobster, Dublin Bay prawn, shlobster (shrimp-lobster), langoustine or shrimp, is a slim, coral colored lobster that grows up to 25 cm (10 in) long, and is "the most important commercial crustacean in Europe". It is now the only extant species in the genus Nephrops, after several other species were moved to the closely related genus Metanephrops. It lives in the north-eastern Atlantic Ocean, and parts of the Mediterranean Sea, but is absent from the Baltic Sea and Black Sea. Adults emerge from their burrows at night to feed on worms and fish.
The large red damselfly is a species of damselflies belonging to the family Coenagrionidae. It is native to the western Palearctic.
The European plaice, commonly referred to as simply plaice, is a species of marine flatfish in the genus Pleuronectes of the family Pleuronectidae.
Cumacea is an order of small marine crustaceans of the superorder Peracarida, occasionally called hooded shrimp or comma shrimp. Their unique appearance and uniform body plan makes them easy to distinguish from other crustaceans. They live in soft-bottoms such as mud and sand, mostly in the marine environment. There are more than 1,500 species of cumaceans formally described. The species diversity of Cumacea increases with depth.
Palinurus elephas is a commonly caught species of spiny lobster from the East Atlantic Ocean and the Mediterranean Sea. Its common names include European spiny lobster, crayfish or cray, crawfish, common spiny lobster, Mediterranean lobster and red lobster.
Neomysis integer is a species of opossum shrimp found in shallow marine bays and estuaries of Europe, with a transparent greenish or brownish body and a large cephalothorax. It is found in very shallow water in both high and low-salinity habitats. It is a filter feeder and the female broods her eggs in a brood pouch beneath her cephalothorax.
Oratosquilla oratoria, the Japanese mantis shrimp, is a species of mantis shrimp found in the western Pacific. It is widely harvested in Japan and eaten as sushi. Like other members of its order it has a powerful spear, which it uses to hunt invertebrates and small fish. It grows to a length of 185 millimetres (7.3 in), and lives at depths of 10–100 metres (33–328 ft).
Echinocardium cordatum, also known as the common heart urchin or the sea potato, is a sea urchin in the family Loveniidae. It is found in sub-tidal regions in temperate seas throughout the world. It lives buried in the sandy sea floor.
Urothoe is a genus of very small marine amphipod crustaceans in the family Urothoidae. Members of the genus are found worldwide.
Nototropis falcatus is a species of amphipod crustacean. It is whitish in colour, with brown patches, and grows to a total length of around 7 mm (0.3 in). It lives on soft sediment such as fine sand at depths of 10 to 50 metres, from northern Norway to the west coast of Ireland, including the North Sea, and as far south as the southern Bay of Biscay.
Oregonia gracilis, commonly known as the graceful decorator crab, is a species of crab belonging to the family Oregoniidae. Like other decorator crabs it habitually attaches other organisms to its back. The sessile organisms are attached to hooked setae that act as a sort of velcro attachment. This decoration provides visual and chemical camouflage thus reducing predation risk. Pacific halibut are a major predator of O. gracilis. Other predators include octopus and sea otters. The main food source of O. gracilis is floating kelp and algae that they capture utilizing a waiting strategy in order to maintain cryptosis.
Caprella mutica, commonly known as the Japanese skeleton shrimp, is a species of skeleton shrimp. They are relatively large caprellids, reaching a maximum length of 50 mm (2.0 in). They are sexually dimorphic, with the males usually being much larger than the females. They are characterized by their "hairy" first and second thoracic segments and the rows of spines on their bodies. Body color ranges from green to red to blue, depending on the environment. They are omnivorous highly adaptable opportunistic feeders. In turn, they provide a valuable food source for fish, crabs, and other larger predators. They are usually found in dense colonies attached to submerged man-made structures, floating seaweed, and other organisms.
The gulf ghost crab, Hoplocypode occidentalis, is a species of ghost crabs native to the Pacific coast of the Americas, from the Gulf of California to Colombia. It is the only species in the genus Hoplocypode. Gulf ghost crabs are medium-sized, reaching a maximum overall body diameter of 6 in (15 cm). They are one of only two ghost crab species found in the eastern Pacific. However, gulf ghost crabs can easily be distinguished from painted ghost crabs by the absence of "horns" on their eyes.
Crangon allmani, also spelled Crangon allmanni, is a species of shrimp in the genus Crangon. It is at home in the northeast Atlantic Ocean. Its specific name, allmani, honours the Irish natural historian George J. Allman. According to J. A. Allen, the spelling allmanni is a writing error and the correct spelling is allmani.