How many species of sea urchin are there?
Sea urchin
Sea urchins or urchins () are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to . Their tests (hard shells) are round and spiny, typically from across. Sea urchins move slowly, crawling with their tube feet, and sometimes pushing themselves with their spines. They feed primarily on algae but also eat slow-moving or sessile animals. Their predators include sea otters, starfish, wolf eels, and triggerfish.
Strongylocentrotus purpuratus
The purple sea urchin, Strongylocentrotus purpuratus, lives along the eastern edge of the Pacific Ocean extending from Ensenada, Mexico to British Columbia, Canada. This sea urchin species is deep purple in color, eggs are orange when secreted in water, and lives in lower inter-tidal and nearshore sub-tidal communities. January, February, and March function as the typical active reproductive months for the species. Sexual maturity is reached around two years.
Sea urchin
Sea urchins are members of the phylum Echinodermata, which also includes sea stars, sea cucumbers, brittle stars, and crinoids. Like other echinoderms, they have five-fold symmetry (called pentamerism) and move by means of hundreds of tiny, transparent, adhesive "tube feet". The symmetry is not obvious in the living animal, but is easily visible in the dried test.
Sea snake
Sea snakes were at first regarded as a unified and separate family, the Hydrophiidae, that later came to comprise two subfamilies: the Hydrophiinae, or true/aquatic sea snakes (now 16 genera with 57 species), and the more primitive Laticaudinae, or sea kraits (one genus, "Laticauda", with five species). Eventually, as just how closely related the sea snakes are to the elapids became clear, the taxonomic situation became less well-defined. Some taxonomists responded by moving the sea snakes to the Elapidae, thereby creating the subfamilies Elapinae, Hydrophiinae, and Laticaudinae, although the latter may be omitted if "Laticauda" is included in the Hydrophiinae. No one has yet been able to convincingly work out the phylogenetic relationships between the various elapid subgroups, and the situation is still unclear. Therefore, others opted to either continue to work with the older traditional arrangements, if only for practical reasons, or to lump all of the genera together in the Elapidae, with no taxonomic subdivisions, to reflect the work that remains to be done.
"*) Not including the nominate subspecies"
Coral Sea
There are at least 30 species of whales, dolphins, and porpoises, including the dwarf minke whale, Indo-Pacific humpback dolphin, humpback whale and dugongs. Six species of sea turtles breed on the GBR – the green sea turtle, leatherback sea turtle, hawksbill turtle, loggerhead sea turtle, flatback turtle and the Olive Ridley.
Araeosoma splendens
Araeosoma splendens is a species of sea urchin of the family Echinothuriidae. Their armour is covered with spines. It is placed in the genus Araeosoma and lives in the sea. Araeosoma splendens was first scientifically described in 1934 by Ole Theodor Jensen Mortensen.
Pseudocentrotus depressus
Pseudocentrotus depressus, commonly known as the pink sea urchin, is a species of sea urchin, one of only two species in the genus "Pseudocentrotus". It was first described in 1864 by the American marine zoologist Alexander Agassiz as "Toxocidaris depressus", having been collected during the North Pacific Exploring and Surveying Expedition undertaken by Captain Cadwalader Ringgold and later Captain John Rodgers.
Psammechinus miliaris
Psammechinus miliaris is a species of sea urchin in the family Parechinidae. It is sometimes known as the green sea urchin or shore sea urchin. It is found in shallow areas of the eastern Atlantic Ocean and the North Sea.
Araeosoma coriaceum
Araeosoma coriaceum is a species of sea urchin of the family Echinothuriidae. Their armour is covered with spines. It is placed in the genus Araeosoma and lives in the sea. Araeosoma coriaceum was first scientifically described in 1879 by Alexander Emanuel Agassiz, an American scientist.
Peter Pritchard
Pritchard's most important and innovative work has been along the Atlantic coast of Guyana, the South American country that is home to four of the world's seven known sea turtle species: the leatherback, green, hawksbill and the olive ridley. By the 1960s, overhunting by local Arawak Indians — themselves an endangered group — had ravaged the turtle population.
Sphaerechinus granularis
Sphaerechinus granularis is a species of sea urchin in the family Toxopneustidae, commonly known as the purple sea urchin. Its range includes the Mediterranean Sea and eastern Atlantic Ocean.
Spawn (biology)
Sea urchins are spiky echinoderms with spherical bodies which usually contain five gonads. They move slowly, feed mostly on seaweed, and are important for the diet of sea otters. Sea urchins are dioecious, having separate male and female sexes, although there is generally no easy way to distinguish the two. The gonads are lined with muscles underneath the peritoneum, and these allow the animal to squeeze its gametes through the duct and into the surrounding sea water, where fertilization takes place. Their roe (male and female gonads) is soft and melting, with a colour ranging from orange to pale yellow, and is sought after as a human delicacy in many parts of the world.
Diadema setosum
Diadema setosum is a species of long-spined sea urchin belonging to the family Diadematidae. It is a typical sea urchin, with extremely long, hollow spines that are mildly venomous. "D. setosum" can be distinguished from other "Diadema" by the characteristic five white dots that can be found on its body. The species is found throughout the Indo-Pacific region, from Australia to Japan and from Africa to the Red Sea. Despite being capable of causing painful stings when stepped upon, the urchin is only slightly venomous and does not pose a serious threat to humans.
Euechinoidea
The subclass Euechinoidea includes almost all living species of sea urchin, and fossil forms going back as far as the Triassic.
Sphaerechinus granularis
"S. granularis" is a large sea urchin, somewhat flattened dorsally and growing to fifteen centimetres in diameter. There are two distinct colour forms. The test is purple in both but one has purple spines and the other white. The spines are short and blunt, all the same length, and arranged neatly in rows.
"S. granularis" is found in the Mediterranean Sea and the eastern Atlantic Ocean, from the Channel Islands south to Cape Verde and the Gulf of Guinea. It favours sheltered locations and lives on rocks covered with seaweed or gravelly substrates. It is usually found in the neritic zone down to about thirty metres but occasionally down to a hundred metres in more exposed locations. It is also found in meadows of the seagrass "Posidonia oceanica".
Phyllacanthus imperialis
Phyllacanthus imperialis, also known as the Sputnik urchin, imperial lance urchin, imperial sea urchin, imperial urchin, pencil sea urchin, lance urchin, knobby sputnik sea urchin, mine urchin, and land mine sea urchin, is a species of sea urchins in the family Cidaridae.
Toxopneustes pileolus
Nevertheless, flower urchins are still considered highly dangerous. The severe debilitating pain of the flower urchin sting compounded by muscular paralysis, breathing problems, numbness, and disorientation can result in accidental drowning among divers and swimmers. The flower urchin was named the "most dangerous sea urchin" in the 2014 "Guinness World Records".
Sea urchins of the Gulf of California
A study from 2005 adds the following species : "Lytechinus anamesus", "Toxopneustes roseus", "Cassidulus pacificus", "Mellita kanakoffi", "Encope wetmorei", "Brissus latecarinatus", "Metalia spatagus", "Brisaster townsendi", "Moira clotho".
Arbacia
Arbacia is a genus of sea urchins, widespread in the Atlantic and east pacific oceans.
Echinus melo
The melon sea urchin is found in the Mediterranean Sea and the eastern Atlantic Ocean between the Azores and the Bay of Biscay, and occasionally as far north as Ireland and Cornwall.
Gracilechinus acutus
The white sea urchin is found in the eastern Atlantic Ocean, the Mediterranean Sea, the North Sea and the English Channel at depths of up to 100 metres on coarse substrates with mud and gravel.
Araeosoma paucispinum
Araeosoma paucispinum is a species of sea urchin of the family Echinothuriidae. Their armour is covered with spines. It is placed in the genus Araeosoma and lives in the sea. Araeosoma paucispinum was first scientifically described in 1924 by Hubert Lyman Clark, an American zoologist.
Turtling (hunting)
While there are several turtle species at risk, the loggerhead sea turtle ("Caretta caretta"), which made the IUCU endangered animals list in 1996, and the leatherback sea turtle ("Dermochelys coriacea") which has been experiencing a decline in numbers, are both still being hunted or killed due to human impact. Another turtle species that can be hunted (not commercially) while considered as special concern at the Canadian and Ontarian level is the snapping turtle ("Chelydra serpentin"). Hawksbill sea turtles have been hunted for their shells primarily to make jewelry. Tourists will often buy items without being informed of the source of the material. Green sea turtles eggs are poached and eaten in many countries; this is also a tourist attraction and taking sea turtle shots, consuming raw turtle egg with whiskey or beer is popular in places like Costa Rica.
Pedinoida
Pedinoida is an order of sea urchins, containing the single living genus "Caenopedina". The group was much more diverse during the Mesozoic, and represents the oldest surviving order of euechinoid sea urchins.
Sea urchin
Like other echinoderms, sea urchin early larvae have bilateral symmetry, but they develop five-fold symmetry as they mature. This is most apparent in the "regular" sea urchins, which have roughly spherical bodies with five equally sized parts radiating out from their central axes. The mouth is at the base of the animal and the anus at the top; the lower surface is described as "oral" and the upper surface as "aboral".
Strongylocentrotus droebachiensis
Sea urchins are dioecious, meaning they either contain male or female reproductive organs. They contain five gonads tucked under the test. These are located close to the anus and are protected by genital plates. One of these plates is perforated, and also acts as the madreporite. Sea urchins all release their eggs or sperm directly into the water column at the same time to ensure fertilization. It is not understood what causes "S. droebachiensis" to release their sperm or eggs, but it may have to do with temperature, because they usually reproduce in early spring.
Aporocidaris incerta
Aporocidaris incerta is a species of sea urchin of the family Ctenocidaridae. It is placed in the genus Aporocidaris and lives in the deep sea. "Aporocidaris incerta" was first scientifically described in 1902 by Koehler. This species lives around the Antarctic continent at depths down to about .
Green sea turtle
The range of the green sea turtle extends throughout tropical and subtropical oceans worldwide. The two major subpopulations are the Atlantic and the eastern Pacific subpopulations. Each population is genetically distinct, with its own set of nesting and feeding grounds within the population's known range. One of the genetic differences between the two subpopulations is the type of mitochondrial DNA found in individual's cells. Individuals from rookeries in the Atlantic Ocean and Mediterranean Sea have a similar type of mitochondrial DNA, and individuals from the Pacific and Indian Oceans have another type of Mitochondrial DNA. Their native range includes tropical to subtropical waters along continental coasts and islands between 30°N and 30°S. Since green sea turtles are a migrating species, their global distribution spans into the open ocean. The differences in mitochondrial DNA more than likely stems from the populations being isolated from each other by the southern tips of both South America and Africa with no warm waters for the green sea turtles to migrate through. The green sea turtle is estimated to inhabit coastal areas of more than 140 countries, with nesting sites in over 80 countries worldwide throughout the year. In the United States Atlantic coast, green sea turtles can be found from Texas and north to Massachusetts. In the United States Pacific coast, they have been found from southern California north to the southernmost tip of Alaska. The largest populations of green sea turtles within the United States coastline are in the Hawaiian Islands and Florida. Globally, the largest populations of sea turtles are in the Great Barrier Reef in Australia and the Caribbean islands.
Diadema antillarum
"Diadema antillarum" is still, in some tropical areas, one of the most abundant, widespread, and ecologically-important shallow-water sea urchins. It is found in the tropical Western Atlantic Ocean, including the Caribbean Sea, Gulf of Mexico and the northern and eastern coasts of South America (as far south as Brazil). It is also found in the East Atlantic at the Canary Islands. This species is ecologically important because it consumes algae that can otherwise grow to such an extent that they can smother coral reefs. They live in holes that are in the reef.
Sea urchin
Urchins typically range in size from , although the largest species can reach up to . They have a rigid, usually spherical body bearing moveable spines, which gives the class the name Echinoidea (from the Greek "ekhinos", spine). The name "urchin" is an old word for hedgehog, which sea urchins resemble; they have archaically been called sea hedgehogs. The name is derived from Old French "herichun", from Latin "ericius", hedgehog.
Plesiocidaris
Plesiocidaris durandi is an extinct species of sea urchins. Including its spines, the creature was 13 cm (5 in) wide. Its remains have been found in Drâ el-Ahmar, near the Atlas Mountains in Oran, Algeria. A Commander Durand found the fossils there in 1870 and sent them to French paleontologists. The exact location of the find was not noted and has not been rediscovered since. The species name, "durandi", refers to Commander Durand. Most "Plesiocidaris" fossils still have the spines attached, indicating they lived in calm water; the spines of dead sea urchins are easily detached by wave currents.
Red sea urchin
The red sea urchin ("Mesocentrotus franciscanus") is a sea urchin found in the northeastern Pacific Ocean from Alaska to Baja California. It lives in shallow waters from the low-tide line to greater than deep, and is typically found on rocky shores sheltered from extreme wave action.
Eucidaris thouarsii
The slate pencil urchin, "Eucidaris thouarsii", is a species of cidaroid sea urchins that inhabits littoral regions of the East Pacific Ocean.
Arbacia lixula
The black sea urchin, "Arbacia lixula" is a species of sea urchin from Europe.
Psammechinus microtuberculatus
Psammechinus microtuberculatus, also known as the green sea urchin, is a species of sea urchin in the family Parechinidae.
List of reptiles of Guatemala
Sea turtles (Cheloniidae) are a family of large tortoises found in all tropical seas and some subtropical and temperate seas. Sea turtles evolved from land turtles about 120 million years ago and are well adapted to life in the sea. Sea turtles eat mostly jellyfish, crustaceans and squid. There are 6 species worldwide, of which at least 5 are currently endangered.Order: Testudines. 
Family: Dermochelyidae
Irregularia
These particular sea urchins are distinguished from other sea urchins by their irregular shape: the anus and often even the mouth are no more at the two poles of the test, creating a bilateral symmetry instead of the classical 5-fold symmetry of echinoderms. The group includes the well known heart urchins, as well as flattened sand dollars, sea biscuits and some other forms. Most of them live inside the sediment, moving in thanks to their particular spines, and feed on its organic fraction.
Coelopleurus exquisitus
The exquisite urchin ("Coelopleurus exquisitus") is a sea urchin species found off the coast of the island of New Caledonia in the Pacific Ocean. It is an epifaunal deepwater species living at depths between and was only identified and named in 2006.
Acanthocidaris curvatispinis
Acanthocidaris curvatispinis is a species of sea urchin of the family Cidaridae. Their armour is covered with spines. It came from the genus Acanthocidaris and lives in the sea. Acanthocidaris curvatispinis was first scientifically described in 1892 by Bell.
Fauna of the United States
In Hawaii, three species of sea turtles are considered native: honu, honu’ea and the leatherback sea turtle. Two other species, the loggerhead sea turtle and the olive ridley sea turtle, are sometimes observed in Hawaiian waters. The Hawaiian green sea turtle is the most common sea turtle in Hawaiian waters. As well as turtles, the sea life consist of more than forty species of shark and the Hawaiian spinner dolphin is widespread. Hawaii's coral reefs are home to over 5000 species, and 25 percent of these are found nowhere else in the world.
Diadema antillarum
"Diadema antillarum" has a test, or "shell," similar to most other sea urchins. What distinguishes the "Diadema" is the length of its spines. Most sea urchin spines are 1–3 cm, but the spines in this species are usually 10–12 cm in length, and can grow as long as 30 cm in very large individuals.
Cidaris cidaris
Cidaris cidaris is a species of sea urchin commonly known as the long-spine slate pen sea urchin. It is found in deep water in the eastern Atlantic Ocean and the Mediterranean Sea.
Overexploitation
One of the sea otters’ primary food sources is the sea urchin. When hunters caused sea otter populations to decline, an ecological release of sea urchin populations occurred. The sea urchins then overexploited their main food source, kelp, creating urchin barrens, areas of seabed denuded of kelp, but carpeted with urchins. No longer having food to eat, the sea urchin became locally extinct as well. Also, since kelp forest ecosystems are homes to many other species, the loss of the kelp caused other cascade effects of secondary extinctions.
Sea Urchin (disambiguation)
A sea urchin is a spiny marine echinoderm.
Stomopneustes variolaris
Stomopneustes variolaris, the black sea urchin or long-spined sea urchin, is a species of sea urchin, the only one in its genus Stomopneustes and only species still alive in its family Stomopneustidae. It is found throughout the tropical Indo-Pacific, with a patchy distribution.
Arbacia punctulata
The Atlantic purple sea urchin is a spherical, dark purple-spined sea urchin, with a nearly flat oral face. It can reach up to 8 cm in diameter, and is native to the North Atlantic Ocean. 
Its natural habitat is in the western Atlantic Ocean. "A. punctulata" can be found in shallow water from Massachusetts to Cuba and the Yucatan Peninsula, from Texas to Florida in the Gulf of Mexico, the coast from Panama to French Guiana, and in the Lesser Antilles, usually on rocky, sandy, or shelly bottoms.
Sea urchin
Together with sea cucumbers (Holothuroidea), they make up the subphylum Echinozoa, which is characterized by a globoid shape without arms or projecting rays. Sea cucumbers and the irregular echinoids have secondarily evolved diverse shapes. Although many sea cucumbers have branched tentacles surrounding their oral openings, these have originated from modified tube feet and are not homologous to the arms of the crinoids, sea stars, and brittle stars.
Echinus melo
Echinus melo, melon sea urchin, is a species of sea urchin in the family Echinidae.
Sea urchin
Echinoids are deuterostome animals, like the chordates. A 2014 analysis of 219 genes from all classes of echinoderms gives the following phylogenetic tree. Approximate dates of branching of major clades are shown in millions of years ago (mya).
Tripneustes ventricosus
Tripneustes ventricosus, commonly called the West Indian sea egg or white sea urchin, is a species of sea urchin. It is common in the Caribbean Sea, the Bahamas and Florida and may be found at depths of less than .
Sea urchin
The gonads of both male and female sea urchins, usually called sea urchin roe or corals, are culinary delicacies in many parts of the world.
In Mediterranean cuisines, "Paracentrotus lividus" is often eaten raw, or with lemon, and known as "ricci" on Italian menus where it is sometimes used in pasta sauces. It can also flavour omelettes, scrambled eggs, fish soup, mayonnaise, béchamel sauce for tartlets, the "boullie" for a soufflé, or Hollandaise sauce to make a fish sauce. In Chilean cuisine, it is served raw with lemon, onions, and olive oil.
Though the edible "Strongylocentrotus droebachiensis" is found in the North Atlantic, it is not widely eaten. However, sea urchins (called "uutuk" in Alutiiq) are commonly eaten by the Alaska Native population around Kodiak Island. It is commonly exported, mostly to Japan.
In the West Indies, slate pencil urchins are eaten.
On the Pacific Coast of North America, "Strongylocentrotus franciscanus" was praised by Euell Gibbons; "Strongylocentrotus purpuratus" is also eaten.
In New Zealand, "Evechinus chloroticus", known as "kina" in Maori, is a delicacy, traditionally eaten raw. Though New Zealand fishermen would like to export them to Japan, their quality is too variable.
In Japan, sea urchin is known as , and its roe can retail for as much as ¥40000 ($360) per kg; it is served raw as "sashimi" or in "sushi", with soy sauce and "wasabi". Japan imports large quantities from the United States, South Korea, and other producers. Japan consumes 50,000 tons annually amounting to over 80% of global production. Japanese demand for sea urchin corals has raised concerns about overfishing.
Native Americans in California are also known to eat sea urchins. The coast of Southern California is known as a source of high quality uni, with divers picking sea urchin from kelp beds in depths as low as 24 m/80 ft. As of 2013, the state was limiting the practice to 300 sea urchin diver licenses.
Sea urchin
The nervous system of sea urchins has a relatively simple layout. With no true brain, the neural center is a large nerve ring encircling the mouth just inside the lantern. From the nerve ring, five nerves radiate underneath the radial canals of the water vascular system, and branch into numerous finer nerves to innervate the tube feet, spines, and pedicellariae.
Urchin (Dungeons &amp; Dragons)
The urchins constitute a family of marine creatures which resemble 3-foot diameter balls of various colors with thousands of radiating 3-inch long spines. An urchin fires its spines at opponents, causing damage. An urchin is usually found in a saltwater habitat, but an urchin has a rolling locomotion on land and is capable of moving at high speed by this means. A dead urchin can be broken up quite easily, and its body contains a gem that varies in value and color according to the type of urchin.
Phormosoma placenta
Phormosoma placenta is a species of sea urchin in the order Echinothurioida. It is a deepwater species, seldom being found at depths less than , and occurs on either side of the Atlantic Ocean on the continental slope.
Hemicentrotus
This sea urchin has a thick test and a large number of tiny, fine, sharp spines. The tubercles are small and closely packed, arranged in slightly zig-zag horizontal rows, with four to eight tubercles on each inter-ambulacral plate and three on each ambulacral plate. The pores are arranged in diagonal lines of four, with the rows being separated by small tubercles. The colour of this sea urchin is pale greenish-olive above and brownish-green below.
Sea urchin
The spines, long and sharp in some species, protect the urchin from predators. Some tropical sea urchins like Diadematidae, Echinothuriidae and Toxopneustidae have venomous spines. Other creatures also make use of these defences; crabs, shrimps and other organisms shelter among the spines, and often adopt the colouring of their host. Some crabs in the Dorippidae family carry sea urchins, starfish, sharp shells or other protective objects in their claws.
Echinidae
Echinidae is a family of sea urchins in the order Echinoida. Members of the family are found in the Atlantic Ocean and the Antarctic.
Bald sea urchin disease
Bald sea urchin disease is a bacterial disease known to affect several species of sea urchins in the Mediterranean Sea, North Atlantic and along the California coastline. Research suggests two pathogens are responsible for the disease, "Listonella anguillarum" and "Aeromonas salmonicida".
Echinoecus
Echinoecus is a genus of crabs that live in association with sea urchins. Formerly considered monotypic, the genus is now thought to contain three species:
Marine National Park, Gulf of Kutch
The fauna found here include:
70 species of sponges are found.
Coral 52 species including 44 
species of hard coral and 10 species of soft coral.
Jellyfish, Portuguese man of war and sea anemones are other coelentrates found here.
Arthropods include 27 species of prawns, 30 species of crabs, lobsters, shrimps and other crustaceans.
Molluscs like pearl oysters and sea slugs are present. Octopus which change colour are also found.
Echinoderms like starfish, sea cucumbers and sea urchins are present.
The fishes found are puffer fishes, sea horse, sting ray, mudskippers and whale sharks which are an endangered species.
Endangered sea turtles such as green sea turtles, olive ridleys and leatherbacks are seen here. There are three species of sea snakes.
There are dugongs and smaller cetaceans like finless porpoises, common dolphins, bottlenose dolphins and Indo-Pacific humpback dolphins. Larger whales such as blue whales, sei whales are seen. Humpback whales, and sperm whales may have been almost wiped out due to illegal whaling by the Soviet Union and Japan. Whale sharks can be found in deeper areas. A surprisingly large scale greater flamingo colony, reaching up to 20,000 nests is known to occur along the gulf. There are 42 islands in the Arabian Sea with coral reefs and the park is situated in one of those.
Sea turtle
Sea turtles are a species that finds relatively low offspring survival rates. If you were to start with 1000 sea turtle eggs, you would end up with only one sexually mature subject. Starting with 1000 eggs, roughly 20% wouldn’t hatch which means from the start only 800 sea turtles will hatch and make it to the sand surface. As the sea turtles begin to move down the beach and towards the waves, only 50% or 400 of them will make it to the ocean. This is due to predation and obstacles preventing the young turtles from reaching the ocean. Continuing, once in the ocean 50% of these sea turtles will survive to past juvenile stages of life. Once they reach adulthood only 20 sea turtles will survive, and this is without human interference. When human interference is factored in, only 2 out of 1000 sea turtles will survive to reproductive maturity.
Sea urchin
Most fossil echinoids from the Paleozoic era are incomplete, consisting of isolated spines and small clusters of scattered plates from crushed individuals, mostly in Devonian and Carboniferous rocks. The shallow-water limestones from the Ordovician and Silurian periods of Estonia are famous for echinoids. Paleozoic echinoids probably inhabited relatively quiet waters. Because of their thin tests, they would certainly not have survived in the wave-battered coastal waters inhabited by many modern echinoids. Echinoids declined to near extinction at the end of the Paleozoic era, with just six species known from the Permian period. Only two lineages survived this period's massive extinction and into the Triassic: the genus "Miocidaris", which gave rise to modern cidaroida (pencil urchins), and the ancestor that gave rise to the euechinoids. By the upper Triassic, their numbers increased again. Cidaroids have changed very little since the Late Triassic, and are the only Paleozoic echinoid group to have survived.
Loxechinus albus
Loxechinus albus is an echinoderm of the family Parechinidae, native to coastal southern South America, ranging from Ecuador, along the entire coasts of Peru and Chile, to Argentina, as well as the Falkland Islands. It is known as the Chilean sea urchin or red sea urchin, but the latter name is typically used for the North Pacific "Mesocentrotus franciscanus" and it is not the only species of sea urchin in Chile (although it is the most common and widespread large sea urchins in that country). "L. albus" is found on rocky reefs and shores in the intertidal and subtidal zones to a depth of .
Diadema (genus)
It is one of the most abundant, widespread, and ecologically important shallow water genera of tropical sea urchins. It is found in all tropical oceans, although is ubiquitous in the Indo-Pacific region, where it inhabits depths down to 70 m. However each species inhabits roughly separate areas of ocean.
Speciation within the genus can be difficult to confirm, partly due to hybridisation, which is at least known to occur between "Diadema savignyi" and "Diadema setosum".
Sea urchin
Mass mortality of sea urchins was first reported in the 1970s, but diseases in sea urchins had been little studied before the advent of aquaculture. In 1981, bacterial "spotting disease" caused almost complete mortality in juvenile "Pseudocentrotus depressus" and "Hemicentrotus pulcherrimus", both cultivated in Japan; the disease recurred in succeeding years. It was divided into a cool-water "spring" disease and a hot-water "summer" form. Another condition, bald sea urchin disease, causes loss of spines and skin lesions and is believed to be bacterial in origin.
Araeosoma leptaleum
Araeosoma leptaleum is a species of sea urchin of the family Echinothuriidae. Their armour is covered with spines. It is placed in the genus Araeosoma and lives in the sea. Araeosoma leptaleum was first scientifically described in 1909 by Alexander Emanuel Agassiz & Hubert Lyman Clark.
Red sea urchin
This animal has a mouth with special jaws (Aristotle's lantern) located on the bottom (oral) surface. Its preferred diet is seaweeds and algae, which it scrapes off and tears up from the sea floor. During larval development, urchins use bands of cilia to capture food from the water column. Red sea urchins found in the channel adjacent to San Juan Island have been found to live a uniquely sedentary lifestyle with the heavy currents bringing an abundance of food.
Collector urchin
The collector urchin ("Tripneustes gratilla") is a species of sea urchin. Collector urchins are found at depths of in the waters of the Indo-Pacific, Hawaii, the Red Sea, and The Bahamas. They can reach in size.
Astropyga radiata
Astropyga radiata, the red urchin, fire urchin, false fire urchin or blue-spotted urchin, is a species of sea urchin in the family Diadematidae. It is a large species with long spines and is found in the tropical Indo-Pacific region. It was first described in 1778 by the German naturalist Nathaniel Gottfried Leske.
Chondrocidaris
Chondrocidaris is a genus of sea urchins of the family Cidaridae described in 1863 by Alexander Agassiz. There are two living species and several fossil species dating as far back as the Miocene.
Sea urchin
The internal organs are enclosed in a hard shell or test composed of fused plates of calcium carbonate covered by a thin dermis and epidermis. The test is rigid, and divides into five ambulacral grooves separated by five interambulacral areas. Each of these areas consists of two rows of plates, so the sea urchin test includes 20 rows of plates in total. The plates are covered in rounded tubercles which contain the sockets to which the spines are attached by ball and socket joints. The inner surface of the test is lined by peritoneum. Sea urchins convert aqueous carbon dioxide using a catalytic process involving nickel into the calcium carbonate portion of the test.
Lytechinus variegatus
Lytechinus variegatus, commonly called the green sea urchin or the variegated sea urchin, is a species of sea urchin that can be found in the warm waters of the western Atlantic Ocean and Caribbean Sea.
Fire urchin
Fire urchin may refer to one of several sea urchins including:
Echinus esculentus
Echinus esculentus, the European edible sea urchin or common sea urchin, is a species of marine invertebrate in the Echinidae family. It is found in coastal areas of western Europe down to a depth of . It is considered "Near threatened" in the IUCN Red List of Threatened Species.
Perischoechinoidea
Perischoechinoidea is a subclass of primitive sea urchins that were abundant in the Palaeozoic seas. However, the great majority of species died out during the Mesozoic, as the more advanced euechinoid sea urchins became common. Today, only a single order, the Cidaroida, survives.
Toxopneustes
Toxopneustes is a genus of sea urchins from the tropical Indo-Pacific. It contains four species. They are known to possess medically significant venom to humans on their pedicellariae (tiny claw-like structures). They are sometimes collectively known as flower urchins, after the most widespread and most commonly encountered species in the genus, the flower urchin ("Toxopneustes pileolus"). Species included in the genus are the following:
Echinothrix calamaris
Echinothrix calamaris, known commonly as the banded sea urchin or double spined urchin among other vernacular names, is a species of sea urchin in the family Diadematidae.
Fauna of Australia
The Australian coast is visited by six species of sea turtle: the flatback, green sea, hawksbill, olive ridley, loggerhead and the leatherback sea turtles; all are protected in Australian waters. There are 35 species of Australian freshwater turtles from eight genera of the family Chelidae. The pig-nosed turtle is the only Australian turtle not of that family. Australia is the only continent without any living species of land tortoise.
Australia is the only continent where venomous snakes outnumber their non-venomous cousins. Australian snakes belong to seven families. Of these, the most venomous species, including the fierce snake, eastern brown snake, taipan and eastern tiger snake are from the family Elapidae. Of the 200 species of elapid, 86 are found only in Australia. Thirty-three sea snakes from family Hydrophiidae inhabit Australia's northern waters; many are extremely venomous. Two species of sea snake from the Acrochordidae also occur in Australian waters. Australia has only 11 species from the world's most significant snake family Colubridae; none are endemic, and they are considered to be relatively recent arrivals from Asia. There are 15 python species and 31 species of insectivorous blind snake.
There are more than 700 species of lizards in Australia with representatives of five families. There are over 130 species in 20 genera of gecko found throughout the Australian continent. The Pygopodidae is a family of limbless lizards endemic to the Australian region; all 39 species from seven genera occur in Australia. The Agamidae or dragon lizards are represented by 70 species in 14 genera, including the thorny devil, bearded dragon and frill-necked lizard. There are 30 species of monitor lizard, family Varanidae, in Australia, where they are commonly known as goannas. The largest Australian monitor is the perentie, which can reach up to 2 m in length. There are about 450 species of skink from more than 40 genera, comprising more than 50% of the total Australian lizard fauna; this group includes the blue-tongued lizards.
Aporocidaris usarpi
Aporocidaris usarpi is a species of sea urchin of the family Ctenocidaridae. Their armour is covered with spines. It is placed in the genus Aporocidaris and lives in the sea. Aporocidaris usarpi was first scientifically described in 2000 by Mooi, David, Fell & Choné.
Sea urchin
The phylogeny of the sea urchins is as follows:
Irrawaddy River
Despite recent declines in the sea turtle populations, five species are known to nest in Burma at well known island and mainland beaches known as turtle-banks. These are the olive ridley sea turtle ("Lepidochelys olivacea"), the loggerhead sea turtle ("Caretta caretta"), the green sea turtle ("Chelonia mydas"), the hawksbill sea turtle ("Eretmochelys imbricata"), and the leatherback sea turtle ("Dermochelys coriacea").
Saving Planet Earth
Of the seven remaining species of sea turtle, six are seriously threatened with extinction. Saira Khan travels to Sri Lanka, one of the best places in the world to see turtles, but even here commercial fishing practices and pressure on the turtles' nesting beaches are driving numbers down.
Araeosoma coriacea
Araeosoma coriacea is a species of sea urchin of the family Echinothuriidae. Their armour is covered with spines. It is placed in the genus Araeosoma and lives in the sea. Araeosoma coriacea was first scientifically described in 1879 by Alexander Emanuel Agassiz, an American scientist.
El Salvador
There are eight species of sea turtles in the world; six of them nest on the coasts of Central America, and four make their home on the Salvadoran coast: the leatherback turtle ("Dermochelys coriacea"), the hawksbill ("Eretmochelys imbricata"), the green sea turtle (black) ("Chelonia agasizzii") and the olive ridley ("Lepidochelys olivacea"). Of these four species, the most common is the olive ridley turtle, followed by the green sea turtle. The other two species, hawksbill and leatherback, are much more difficult to find as they are critically endangered, while the olive ridley and green sea turtle are in danger of extinction.
Sea Urchins
Described as a saltwater Swallows and Amazons, it was shot on the Mahurangi Peninsula near Puhoi in the Hauraki Gulf, where the plucky “urchins” stumble on villainous plots from missing treasure to wildlife smuggling while holidaying with their uncle.
Slate pencil urchin
Slate pencil urchin is a common name for several sea urchin species with blunt spines:
Psammechinus
Psammechinus is a genus of sea urchins in the family Parechinidae containing two species:
Ras Muhammad National Park
The area is home to more than 1000 species of fish, 40 species of star fish, 25 species of sea urchins, more than a 100 species of mollusc and 150 species of crustaceans. Among others, sea turtles, such as the green turtle ("Chelonia mydas") and the hawksbill turtle ("Eretmochelys imbricata") appear regularly in Ras Mohammad.
Diadema paucispinum
Diadema paucispinum, the long-spined sea urchin, is a species of sea urchin in the family Diadematidae. It is found in the western Indo-Pacific Ocean and in Hawaii and other east Pacific islands.
Dermechinus
Dermechinus is a genus of sea urchin in the family Echinidae found in deep water in the southern Indian, Pacific and Atlantic Oceans. It is monotypic, with Dermechinus horridus, sometimes called the cactus urchin, being the only species.
Leatherback sea turtle
The leatherback sea turtle ("Dermochelys coriacea"), sometimes called the lute turtle or leathery turtle or simply the luth, is the largest of all living turtles and is the fourth-heaviest modern reptile behind three crocodilians. It is the only living species in the genus Dermochelys and family Dermochelyidae. It can easily be differentiated from other modern sea turtles by its lack of a bony shell, hence the name. Instead, its carapace is covered by skin and oily flesh. "Dermochelys" is the only extant genus of the family Dermochelyidae.
Asthenosoma marisrubri
Asthenosoma marisrubri ('flexible body of the Red Sea') (Weinberg & De Ridder, 1998) aka Red Sea fire urchin and toxic leather sea urchin , is a relatively common sea urchin with a widespread distribution in the Indo-Pacific, and was till 1998 considered a color variant of "Asthenosoma varium". Sea urchins are close relatives of starfish, crinoids, brittle stars and sea cucumbers, all being echinoderms ('spiny skins').
Strongylocentrotus purpuratus
The sea urchin genome is estimated to encode about 23,500 genes. The "S. purpuratus" has 353 protein kinases, containing members of 97% of human kinase subfamilies. Many of these genes were previously thought to be vertebrate innovations or were only known from groups outside the deuterostomes. The team sequencing the species concluded that some genes are not vertebrate specific as thought previously, while other genes still were found in the urchin but not the chordate.
Gracilechinus acutus
Gracilechinus acutus is a species of sea urchin in the family Echinidae, commonly known as the white sea urchin. It is an omnivore and feeds on algae and small invertebrates.
Sea urchin
Sea urchins can be found in all climates, from warm seas to polar oceans. The larvae of the polar sea urchin "Sterechinus neumayeri" have been found to use energy in metabolic processes twenty-five times more efficiently than do most other organisms. Despite their presence in nearly all the marine ecosystems, most species are found on temperate and tropical coasts, between the surface and some tens of meters deep, close to photosynthetic food sources.
Sea urchin
Most sea urchins possess five pairs of external gills attached to the peristomial membrane around their mouths. These thin-walled projections of the body cavity are the main organs of respiration in those urchins that possess them. Fluid can be pumped through the gills' interiors by muscles associated with the lantern, but this does not provide a continuous flow, and occurs only when the animal is low in oxygen. Tube feet can also act as respiratory organs, and are the primary sites of gas exchange in heart urchins and sand dollars, both of which lack gills. The inside of each tube foot is divided by a septum which reduces diffusion between the incoming and outgoing streams of fluid.
Sea urchin
The organism's evolutionary placement and unique embryology with five-fold symmetry were the major arguments in the proposal to seek the sequencing of its genome. Importantly, urchins act as the closest living relative to chordates and thus are of interest for the light they can shed on the evolution of vertebrates. The genome of "Strongylocentrotus purpuratus", was completed in 2006 and established homology between sea urchin and vertebrate immune system-related genes. Sea urchins code for at least 222 Toll-like receptor genes and over 200 genes related to the Nod-like-receptor family found in vertebrates. This increases its usefulness as a valuable model organism for studying the evolution of innate immunity. The sequencing also revealed that while some genes were thought to be limited to vertebrates, there were also innovations that have previously never been seen outside the chordate classification, such as immune transcription factors PU.1 and SPIB.
Strongylocentrotus purpuratus
The purple sea urchin, along with sea otters and abalones, is a prominent member of the kelp forest community. Sea urchins have been used for food by the indigenous peoples of California, who ate the yellow egg mass raw. The purple sea urchin also plays a key role in the disappearance of kelp forests that is currently occurring due to climate change.
Pedicellaria
Four main forms of pedicellariae are found in sea urchins : tridactylous, ophicephalous, triphyllous and globiferous. There are typically three valves that make up the jaw of sea urchin pedicellaria. The stalk is composed of a skeletal rod and a flexible neck portion.
They are generally attached by a long, inflexible stalk and may be found anywhere on the sea urchin's test.
In some families, globigerous pedicellariae have evolved into venomous structures, used for protection or maybe hunting. This is particularly the case in the family Toxopneustidae, some species such as "Tripneustes gratilla" and especially "Toxopneustes pileolus" being extremely venomous.
Hemicentrotus
Hemicentrotus pulcherrimus is a species of sea urchin, the only one in the monotypic genus Hemicentrotus. It was first described by the American engineer and marine zoologist Alexander Agassiz in 1864 as "Psammechinus pulcherrimus". Its range extends along the coasts of Korea and China, and in Japan from Kyūshū to Ishikari Bay. An edible species, it is harvested from Kyūshū to Fukui, in the Sea of Japan.
Gracilechinus
Gracilechinus is a genus of sea urchins in the family Echinidae.