Cape lobster | |
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Herbst's 1792 illustration [Note 1] | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Subphylum: | Crustacea |
Class: | Malacostraca |
Order: | Decapoda |
Suborder: | Pleocyemata |
Family: | Nephropidae |
Genus: | Homarinus Kornfield, Williams & Steneck, 1995 [2] |
Species: | H. capensis |
Binomial name | |
Homarinus capensis | |
Synonyms [4] | |
The Cape lobster, Homarinus capensis, is a species of small lobster that lives off the coast of South Africa, from Dassen Island to Haga Haga. Only a few dozen specimens are known, mostly regurgitated by reef-dwelling fish. It lives in rocky reefs, and is thought to lay large eggs that have a short larval phase, or that hatch directly as a juvenile. The species grows to a total length of 10 cm (3.9 in), and resembles a small European or American lobster; it was previously included in the same genus, Homarus , although it is not very closely related to those species, and is now considered to form a separate, monotypic genus – Homarinus. Its closest relatives are the genera Thymops and Thymopides .
The Cape lobster is endemic to South Africa. It occurs from Dassen Island, Western Cape in the west to Haga Haga, Eastern Cape in the east, a range of 900 kilometres (560 mi). [5] Most of the known specimens were regurgitated by fish caught on reefs at depths of 20–40 metres (66–131 ft). [5] This suggests that the Cape lobster inhabits rocky substrates, and may explain its apparent rarity, since such areas are not amenable to dredging or trawling, and the species may be too small to be retained by lobster traps. [5]
Homarinus capensis is considerably smaller than the large northern lobsters of the Atlantic Ocean, Homarus gammarus (the European lobster) and Homarus americanus (the American lobster), at 8–10 centimetres (3.1–3.9 in) total length, or 4–5 cm (1.6–2.0 in) carapace length. [4] [6] Accounts of the colouration of H. capensis are very variable, from tawny, red or yellow to "a rather dark olive", similar to Homarus gammarus. [7]
Homarinus and Homarus are considered to be the most plesiomorphic genera in the family Nephropidae. [8] Nonetheless, the Cape lobster differs from Homarus in a number of characters. The rostrum of the Cape lobster is flattened, while that of Homarus is rounded in section, and curves upwards at the tip. [5] The three pairs of claws [Note 1] are covered with hairs in Homarinus, while those of Homarus are hairless. [4] The telson tapers along its length in Homarus, but has sides which are nearly parallel in Homarinus. [5] Although no egg-bearing females have been collected, the gonopores (openings of the oviducts) of female Cape lobsters are much larger than those of Homarus gammarus and Homarus americanus. [5] This is thought to indicate that Homarinus bears fewer, larger eggs than Homarus, and that either the larvae develop quickly into juveniles after hatching, or that the eggs hatch directly into juveniles. [5] [10]
Cape lobsters are elusive and rare, with only fourteen specimens having been collected between 1792 (the date of its first description) and 1992. [7] These include five males in the collections of the South African Museum (Cape Town), two in the Natural History Museum (London), one in each of the East London Museum, the Rijksmuseum van Natuurlijke Historie (Leiden) and the Albany Museum (Grahamstown), and one male and one female in the Muséum national d'histoire naturelle (Paris). [6] In 1992, a Cape lobster was discovered at Dassen Island, and the publicity the find generated resulted in more than 20 additional specimens being reported. [5]
The Cape lobster was first described by Johann Friedrich Wilhelm Herbst in 1792 as Cancer (Astacus) capensis. [9] [11] It was independently described in 1793 by Johan Christian Fabricius as Astacus flavus, possibly based on the same type specimen. [9] When Friedrich Weber erected the genus Homarus in 1795, he included Fabricius' species in it, but this placement was not followed by later authors. [9] The species reached its current classification in 1995, when the monotypic genus Homarinus was erected by Irv Kornfield, Austin B. Williams and Robert S. Steneck. [7]
While analyses of morphology suggest a close relationship between Homarinus and Homarus, molecular analyses using mitochondrial DNA reveal that they are not sister taxa. [8] Both genera lack ornamentation such as spines and carinae, but are thought to have reached that state independently, through convergent evolution. [8] The closest living relative of Homarus is Nephrops norvegicus , while the closest relatives of Homarinus are Thymops and Thymopides . [8]
Lobsters are a family of marine crustaceans. They have long bodies with muscular tails and live in crevices or burrows on the sea floor. Three of their five pairs of legs have claws, including the first pair, which are usually much larger than the others. Highly prized as seafood, lobsters are economically important and are often one of the most profitable commodities in the coastal areas they populate.
The American lobster is a species of lobster found on the Atlantic coast of North America, chiefly from Labrador to New Jersey. It is also known as Atlantic lobster, Canadian lobster, true lobster, northern lobster, Canadian Reds, or Maine lobster. It can reach a body length of 64 cm (25 in), and a mass of over 20 kilograms (44 lb), making it not only the heaviest crustacean in the world, but also the heaviest of all living arthropod species. Its closest relative is the European lobster Homarus gammarus, which can be distinguished by its coloration and the lack of spines on the underside of the rostrum. American lobsters are usually bluish green to brown with red spines, but several color variations have been observed.
Homarus is a genus of lobsters, which include the common and commercially significant species Homarus americanus and Homarus gammarus. The Cape lobster, which was formerly in this genus as H. capensis, was moved in 1995 to the new genus Homarinus.
Homarus gammarus, known as the European lobster or common lobster, is a species of clawed lobster from the eastern Atlantic Ocean, Mediterranean Sea and parts of the Black Sea. It is closely related to the American lobster, H. americanus. It may grow to a length of 60 cm (24 in) and a mass of 6 kilograms (13 lb), and bears a conspicuous pair of claws. In life the lobsters are blue, only becoming "lobster red" on cooking. Mating occurs in the summer, producing eggs which are carried by the females for up to a year before hatching into planktonic larvae. Homarus gammarus is a highly esteemed food, and is widely caught using lobster pots, mostly around the British Isles.
Lobsters are widely fished around the world for their meat. They are often hard to catch in large numbers, but their large size can make them a profitable catch. Although the majority of the targeted species are tropical, the majority of the global catch is in temperate waters.
Nephrops is a genus of lobsters comprising a single extant species, Nephrops norvegicus, and several fossil species. It was erected by William Elford Leach in 1814, to accommodate N. norvegicus alone, which had previously been placed in genera such as Cancer, Astacus or Homarus. Nephrops means "kidney eye" and refers to the shape of the animal's compound eye.
Metanephrops challengeri is a species of slim, pink lobster that lives around the coast of New Zealand. It is typically 13–18 cm (5–7 in) long and weighs around 100 g (3.5 oz). The carapace and abdomen are smooth, and adults are white with pink and brown markings and a conspicuous pair of long, slim claws. M. challengeri lives in burrows at depths of 140–640 m (460–2,100 ft) in a variety of sediments. Although individuals can live for up to 15 years, the species shows low fecundity, where small numbers of larvae hatch at an advanced stage.
Reef lobsters, Enoplometopus, are a genus of small lobsters that live on reefs in the Indo-Pacific, Caribbean and warmer parts of the Atlantic Ocean.
Astacidae is a family of freshwater crayfish native to Europe and western North America. The family is made up of four extant (living) genera: The genera Astacus, Pontastacus, and Austropotamobius are all found throughout Europe and parts of western Asia, while Pacifastacus is found on the Pacific coast of the United States and British Columbia and includes the signal crayfish and the Shasta crayfish.
The family Thaumastochelidae contains five known species of deep-sea lobsters, three in the genus Thaumastocheles, and two in the genus Thaumastochelopsis. The fifth species was discovered in the ten–year Census of Marine Life. These creatures are distinguished from other clawed lobsters by their blindness, and by their single elongated, spiny chela.
Metanephrops is a genus of lobsters, commonly known as scampi. Important species for fishery include Metanephrops australiensis and Metanephrops challengeri. It differs from other lobsters such as Homarus and Nephrops norvegicus in that its two main claws are of equal size, rather than being differentiated into a crusher and a pincher. There are 18 extant species recognised in the genus:
Justitia is a genus of spiny lobsters. Following the recognition of Nupalirus as a separate genus, Justitia comprises one extant species and two fossil species:
Thymops birsteini, the Patagonian lobsterette, is a species of lobster found around the coasts of South America, particularly the South Atlantic. It belongs to the monotypic genus Thymops.
Scyllarides latus, the Mediterranean slipper lobster, is a species of slipper lobster found in the Mediterranean Sea and in the eastern Atlantic Ocean. It is edible and highly regarded as food, but is now rare over much of its range due to overfishing. Adults may grow to 1 foot (30 cm) long, are camouflaged, and have no claws. They are nocturnal, emerging from caves and other shelters during the night to feed on molluscs. As well as being eaten by humans, S. latus is also preyed upon by a variety of bony fish. Its closest relative is S. herklotsii, which occurs off the Atlantic coast of West Africa; other species of Scyllarides occur in the western Atlantic Ocean and the Indo-Pacific. The larvae and young animals are largely unknown.
Panulirus homarus is a species of spiny lobster that lives along the coasts of the Indian and Pacific Oceans. It lives in shallow water, and feeds on the brown mussel Perna perna. It typically grows to a length of 20–25 cm (7.9–9.8 in). Alongside the dark green nominate subspecies, two red subspecies are recognised, one around the Arabian Peninsula, and one around southern Africa. It is the subject of small-scale fishery.
Scyllarus pygmaeus is a species of slipper lobster that lives in shallow water in the Mediterranean Sea and eastern Atlantic Ocean. It grows to a length of 55 mm (2.2 in), which is too small for it to be fished for food. The juvenile form was first described in 1885, with the description of the adult following in 1888 as a result of the Challenger expedition.
Nicothoe tumulosa is a species of copepod parasitic on the gills of the glypheoid lobster Neoglyphea inopinata. It was described as a new species in 1976 by Roger F. Cressey. It can be differentiated from related species by the setal formula, and the trunk's covering of small bumps, which give the species its name.
Thymopides is a genus of deep-water lobsters, comprising the two species Thymopides grobovi and Thymopides laurentae.
Nephropides caribaeus is a species of lobster, the only species in the genus Nephropides. It is found in western parts of the Caribbean Sea, from Belize to Colombia. It grows to a total length of around 170 mm (6.7 in), and is covered in conspicuous tubercles.
Geryon trispinosus is a species of crab that lives in deep water in the north-eastern Atlantic Ocean.
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