| Ligia exotica | |
|---|---|
 | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Malacostraca |
| Order: | Isopoda |
| Suborder: | Oniscidea |
| Family: | Ligiidae |
| Genus: | Ligia |
| Species: | L. exotica |
| Binomial name | |
| Ligia exotica Roux, 1828 [1] | |
Ligia exotica, also called sea roach [2] or wharf roach, [3] is a woodlouse-like isopod, a sea slater in the family Ligiidae. It is found in various parts of the world living on rocky coasts and harbour walls just above high water mark.
Ligia exotica can grow to 4 centimetres (1.6 inches) in length, with the males being rather bigger than the females. The general colour is dark grey, sometimes with brown flecks, and the appendages are pale brown. The head has a pair of long antennae which exceed the length of the body, and two unstalked, bulging eyes. The body is flattened dorsally and has seven thoracic segments, each with a pair of legs, and six abdominal segments. The first five of these bear flat, membranous gills and the sixth bears a pair of long, forked uropods. [3] [4]
Ligia exotica is believed to be native to the coasts of Western Europe and the Mediterranean Sea. Other authorities suggest it originated in the Pacific and Indian Oceans. [5] The fact that Roux gave it the specific name "exotica" when he first described the species in 1828 from near Marseilles, may indicate that it was not previously known in that locality. It has spread to many other temperate and subtropical parts of the world including the Red Sea, the eastern seaboard of the United States and Hawaii. It is thought that the spread occurred unintentionally via shipping, [6] either in ballast or between the planks of timber ships. [3] Its natural habitat is rocks and cliffs in the splash zone just above high water mark where it lives in damp crevices. It is also found, sometimes in large numbers, on jetties and harbour walls. [3]
Ligia exotica is both a grazer on microalgae and diatoms [3] and a scavenger on plant remains and detritus. [6] In the eastern United States, where it is considered to be invasive, it seems to be the dominant invertebrate in its habitat. The impact of this on competing organisms and its contribution to the diet of predators has not been properly evaluated, however the NEMESIS database suggests it is not likely to be of much significance. [7]
Individual Ligia exotica are either male or female. Fertilization is internal and eggs are laid in batches of about eighty in moist cracks and fissures. Females often carry their eggs around with them using specially adapted appendages. The larvae develop into juveniles which go through a number of moults before becoming adult. [3]
Ligia exotica has a passive water transportation system through open capillaries in its legs. [8]
Sea spiders are marine arthropods of the order Pantopoda, belonging to the class Pycnogonida, hence they are also called pycnogonids. They are cosmopolitan, found in oceans around the world. The over 1,300 known species have leg spans ranging from 1 mm (0.04 in) to over 70 cm (2.3 ft). Most are toward the smaller end of this range in relatively shallow depths; however, they can grow to be quite large in Antarctic and deep waters.
Isopoda is an order of crustaceans. Members of this group are called isopods and include both aquatic species, and terrestrial species such as woodlice. 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.
The superorder Peracarida is a large group of malacostracan crustaceans, having members in marine, freshwater, and terrestrial habitats. They are chiefly defined by the presence of a brood pouch, or marsupium, formed from thin flattened plates (oostegites) borne on the basalmost segments of the legs. Peracarida is one of the largest crustacean taxa and includes about 12,000 species. Most members are less than 2 cm (0.8 in) in length, but the largest is probably the giant isopod which can reach 76 cm (30 in). The earliest known perecaridian was Oxyuropoda ligioides, a fossil of which has been found dating to the Late Devonian of Ireland.
Ligia oceanica, the sea slater, common sea slater, or sea roach, is a woodlouse, living in the littoral zone—rocky seashores of the European North Sea and Atlantic coastlines.
Sabellidae, or feather duster worms, are a family of marine polychaete tube worms characterized by protruding feathery branchiae. Sabellids build tubes out of a tough, parchment-like exudate, strengthened with sand and bits of shell. Unlike the other sabellids, the genus Glomerula secretes a tube of calcium carbonate instead. Sabellidae can be found in subtidal habitats around the world. Their oldest fossils are known from the Early Jurassic.
Woodlice are terrestrial isopods in the suborder Oniscidea. Their name is derived from being often found in old wood, and from louse, a parasitic insect, although woodlice are neither parasitic nor insects.
A giant isopod is any of the almost 20 species of large isopods in the genus Bathynomus. They are abundant in the cold, deep waters of the Atlantic, Pacific, and Indian Oceans. Bathynomus giganteus, the species upon which the generitype is based, is often considered the largest isopod in the world, though other comparably poorly known species of Bathynomus may reach a similar size. The giant isopods are noted for their resemblance to the much smaller common woodlouse, to which they are related.
Crustaceans may pass through a number of larval and immature stages between hatching from their eggs and reaching their adult form. Each of the stages is separated by a moult, in which the hard exoskeleton is shed to allow the animal to grow. The larvae of crustaceans often bear little resemblance to the adult, and there are still cases where it is not known what larvae will grow into what adults. This is especially true of crustaceans which live as benthic adults, more-so than where the larvae are planktonic, and thereby easily caught.
Chirocephalus diaphanus is a widely distributed European species of fairy shrimp that lives as far north as Great Britain, where it is the only surviving species of fairy shrimp and is protected under the Wildlife and Countryside Act 1981. It is a translucent animal, about 0.5 in (13 mm) long, with reddened tips to the abdomen and appendages. The body comprises a head, a thorax bearing 11 pairs of appendages, and a seven-segmented abdomen. In males, the antennae are enlarged to form "frontal appendages", while females have an egg pouch at the end of the thorax.
Idotea balthica is a species of marine isopod which lives on seaweed and seagrass in the subtidal zone of rocky shores and sandy lagoons.
Hemioniscus balani, a species of isopod crustacean, is a widespread parasitic castrator of barnacles in the northern Atlantic Ocean. Its range extends from Norway to the Atlantic coast of France, and as far west as Massachusetts. It is also commonly found on the Pacific coast of North America; it is not known if the Pacific and Atlantic populations are the same species, or if the Pacific population exists following human-assisted introduction.
Sphaeroma terebrans is a mangrove-boring isopod, first described by Spence Bate in 1866. It is 8–10 millimetres (0.31–0.39 in) long, and is thought to have been introduced to North America by wooden-hulled ships. The isopod is found throughout the Gulf of Mexico mainly in mangrove swamps of Louisiana and Florida. S. terebrans will also bore into boats, wooden pilings and other wooden structures.
Ligia is a genus of isopods, commonly known as rock lice or sea slaters. Most Ligia species live in tidal zone cliffs and rocky beaches, but there are several fully terrestrial species which occur in high-humidity environments.
Ligia cinerascens is a woodlouse in the family Ligiidae.
Pennella balaenopterae is a large ectoparasitic copepod specialising in parasitising marine mammals. It is the largest member of the genus Pennella, the other species of which are parasites of larger marine fish.
Aega antarctica is a species of isopod crustacean. It is a temporary ectoparasite of fish, feeding on the fish's blood and then dropping to the seabed to digest its meal over a period of several months. It is found in the seas around Antarctica.
Crustaceans are invertebrate animals that constitute one group of arthropods that are a part of the subphylum Crustacea, a large, diverse group of mainly aquatic arthropods including decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, opossum shrimps, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed pan-group referred to as Pancrustacea. The three classes Cephalocarida, Branchiopoda and Remipedia are more closely related to the hexapods than they are to any of the other crustaceans.
Panulirus guttatus, the spotted spiny lobster or Guinea chick lobster, is a species of spiny lobster that lives on shallow rocky reefs in the tropical West Atlantic and Caribbean Sea.
Deto echinata, the horned isopod, is a species of air-breathing isopod, or woodlouse, in the family Detonidae. It inhabits seashores in southern Africa and on some oceanic islands.
Ligia platycephala is a species of isopod from the genus Ligia.
Data related to Ligia exotica at Wikispecies