| Orange knobby star | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Class: | Asteroidea |
| Order: | Spinulosida |
| Family: | Echinasteridae |
| Genus: | Echinaster |
| Species: | E. echinophorus |
| Binomial name | |
| Echinaster echinophorus | |
| Synonyms [1] | |
| |
The orange knobby star, Echinaster echinophorus, is a species of sea star found in the Caribbean Sea and along the Atlantic coast of South America.
It is a small species with a diameter of up to 7 cm (2.8 in). It has a small central disc and five spatulate arms, tapering very little and with rounded tips. The arms are oval in cross section and on the aboral (upper) side have one or two rows of bluntly conical spines, and more rows of spines on the sides of the arms and on the oral (under) surface, on either side of the ambulacral grooves. The colour is usually some shade of red or orange. [2] [3]
Echinaster echinophorus is found in shallow water in Florida, the Caribbean Sea, the Bahamas, Venezuela, and northern Brazil at depths ranging from 24 to 73 m (79 to 240 ft) and at a sea temperature of about 27 °C (8 °F). [1] It occurs on reefs, rocks, and areas of coral rubble and sometimes among mangroves. [3]
In Florida, Echinaster echinophorus spawns in late spring and early summer. Two types of egg are produced, some being dark-coloured and planktonic while others are bright orange and immediately sink to the seabed. [4] These soon start to develop into modified brachiolaria larvae, which have larval arms and attach with a sucker. By day seven they have two pairs of tube feet and begin to move around. The development of the pelagic eggs takes place much more slowly. [4]
A study testing secondary metabolites obtained from Echinaster echinophorus found an extract from its tissues showed activity against Leishmania amazonensis, the protozoan parasite causing the tropical skin disease leishmaniasis, and it was not toxic to the mice on which it was tested. [5]
Orange knobbly stars feed on many species of sponges, but the red tree sponge ( Haliclona compressa ) contains certain secondary metabolites that prevent the starfish from eating it. [6]
An echinoderm is any member of the phylum Echinodermata of marine animals. The adults are recognizable by their radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the sea lilies or "stone lilies". Adult echinoderms are found on the sea bed at every ocean depth, from the intertidal zone to the abyssal zone. The phylum contains about 7000 living species, making it the second-largest grouping of deuterostomes, after the chordates. Echinoderms are the largest phylum that has no freshwater or terrestrial members.
Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea. Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish are also known as asteroids due to being in the class Asteroidea. About 1,900 species of starfish occur on the seabed in all the world's oceans, from warm, tropical zones to frigid, polar regions. They are found from the intertidal zone down to abyssal depths, at 6,000 m (20,000 ft) below the surface.
Panulirus argus, the Caribbean spiny lobster, is a species of spiny lobster that lives on reefs and in mangrove swamps in the western Atlantic Ocean.
A spongivore is an animal anatomically and physiologically adapted to eating animals of the phylum Porifera, commonly called sea sponges, for the main component of its diet. As a result of their diet, spongivore animals like the hawksbill turtle have developed sharp, narrow bird-like beak that allows them to reach within crevices on the reef to obtain sponges.
The Echinasteridae are a family of starfish in the monotypic order Spinulosida. The family includes eight genera and about 133 species found on the seabed in various habitats around the world.
The queen angelfish, also known as the blue angelfish, golden angelfish or yellow angelfish, is a species of marine angelfish found in the western Atlantic Ocean. It is a benthic, warm-water species that lives in coral reefs. It is recognized by its blue and yellow coloration and a distinctive spot or "crown" on its forehead. This crown distinguishes it from the closely related and similar looking Bermuda blue angelfish, with which it overlaps in range and can interbreed.
Agelas clathrodes, also known as the orange elephant ear sponge, is a species of sea sponge. It lives on reefs in the Caribbean, usually more than 10 metres (33 ft) below the surface of the ocean. It takes various forms, and its color is reddish orange.
The giant barrel sponge is the largest species of sponge found growing on Caribbean coral reefs. It is common at depths greater than 10 metres (33 ft) down to 120 metres (390 ft) and can reach a diameter of 1.8 metres. It is typically brownish-red to brownish-gray in color, with a hard or stony texture. The giant barrel sponge has been called the "redwood of the reef" because of its size and estimated lifespan of hundreds to a thousand or more years. It is perhaps the best-studied species of sponge in the sea; a population on Conch Reef, in the Florida Keys, has been monitored and studied since 1997.
Oreaster reticulatus, commonly known as the red cushion sea star or the West Indian sea star, is a species of marine invertebrate, a starfish in the family Oreasteridae. It is found in shallow water in the western Atlantic Ocean and the Caribbean Sea.
Amphimedon compressa, the erect rope sponge, red tree sponge, red tubular sponge, or red sponge is a demosponge found in southern Florida, the Caribbean Sea, and the Bahamas. It can be deep red, orange, brown, or black.
Luidia clathrata is a tropical species of starfish in the family Luidiidae. It is variously known as the slender-armed starfish, the gray sea star, or the lined sea star. It is found in the western Atlantic Ocean.
Leptasterias hexactis is a species of starfish in the family Asteriidae, commonly known as the six-rayed star. It is found in the intertidal zone of the western seaboard of the United States. It is a predator and is unusual among starfish in that it broods its eggs and young.
Aspidodiadema jacobyi is a small sea urchin in the family Aspidodiadematidae. It lives in tropical seas at great depths. Aspidodiadema jacobyi was first scientifically described in 1880 by Alexander Emanuel Agassiz, an American scientist.
Pteraster tesselatus, the slime star or cushion star, is a species of starfish in the family Pterasteridae found in the North Pacific.
Echinaster spinulosus, the small spine sea star, is a species of sea star found in shallow parts of the western Atlantic Ocean, the Caribbean Sea and Gulf of Mexico.
Pteraster militaris, the wrinkled star, is a species of starfish in the family Pterasteridae. It is found in the northern Pacific Ocean, the Arctic Ocean, the Barents Sea and the northern Atlantic Ocean.
Astropecten duplicatus, the two-spined sea star, is a starfish in the family Astropectinidae. It is found in the eastern Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico.
Marthasterias is a genus of starfish in the family Asteriidae. It is monotypic and the only species in the genus is Marthasterias glacialis, commonly known as the spiny starfish. It is native to the eastern Atlantic Ocean.
Echinaster is a well-studied and common genus of starfish containing ~30 species and is the second-largest genus found within the family Echinasteridae. The genera Henricia and Echinaster encompass 90% of all the species found within the family Echinasteridae. It contains 30 species, however the number of species in this genus is still debatable because of uncertainty within the genera. This genus is currently sub-divided into two sub-genera: Echinaster and Othilia, evolutionary relationships between the sub-genera is not understood. Echinaster are found in the Pacific, Atlantic and Indian oceans, with most species being studied in the Gulf of Mexico and Brazil. The sub-genera Othilia is thought to encompass species mainly found in the Gulf of Mexico and Brazil. Echinaster is often one of the most studied species within the family Echinasteridae and is often used to find evolutionary relationships.
Dysidea etheria, commonly known as the ethereal sponge or heavenly sponge, is a species of lobate sponge within the class Demospongiae. This marine sponge is known for its light blue color and can be found in the Caribbean as well as off the coasts of Florida and Georgia. Like all other poriferans, D. etheria is capable of both sexual and asexual reproduction. The use of spicule collection as well as chemical defenses allows D. etheria to protect itself against predators such as the zebra doris and the orange knobby star. D. etheria is also known as a host species of the invasive brittle star Ophiothela mirabilis. Lastly, various molecular biology studies have utilized D. etheria to both study foreign particle transport in sponges and to isolate novel molecules.