Oligochaeta is a subclass of soft-bodied animals in the phylum Annelida, which is made up of many types of aquatic and terrestrial worms, including all of the various earthworms. Specifically, oligochaetes comprise the terrestrial megadrile earthworms, and freshwater or semiterrestrial microdrile forms, including the tubificids, pot worms and ice worms (Enchytraeidae), blackworms (Lumbriculidae) and several interstitial marine worms.
Megascolecidae is a taxonomic family of earthworms native to Madagascar, Australia, New Zealand, Asia, and North America. All species of the Megascolecidae belong to the Clitellata class. The Megascolecidae comprise a large family of earthworms and they can grow up to 2 meters in length. The intercontinental distribution of Megascolecidae species favours the continental drift theory.
Acoelomorpha is a subphylum of very simple and small soft-bodied animals with planula-like features which live in marine or brackish waters. They usually live between grains of sediment, swimming as plankton, or crawling on other organisms, such as algae and corals. With the exception of two acoel freshwater species, all known acoelomorphs are marine.
Ice worms are enchytraeid annelids of the genus Mesenchytraeus. The majority of the species in the genus are abundant in gravel beds or the banks of riverine habitats, but the best-known members of the genus are found in glacial ice. They include the only annelid worms known to spend their entire lives in glacial ice, and some of the few metazoans to complete their entire life cycle at conditions below 0 °C (32 °F).
Mesenchytraeus solifugus, commonly called an ice worm, is a species of oligochaete worm that inhabits coastal glaciers in northwestern North America. M. solifugus is dark brown and grows to about 15 mm long and 0.5 mm wide. It has a high population density and is common in suitable habitat. It can only survive at temperatures of approximately –7 °C to 5 °C. The ice worm is studied for its ability to survive in low temperatures. It has heavy pigment, absorbing most colors; however, it burrows into the glacier to avoid strong sunlight.
Xenoturbella is a genus of very simple bilaterians up to a few centimeters long. It contains a small number of marine benthic worm-like species.
Arthur Adams was an English physician and naturalist.
Chromodorididae, or chromodorids, are a taxonomic family of colourful, sea slugs; dorid nudibranchs, marine gastropod mollusks in the superfamily Doridoidea. “Chromodorid nudibranchs are among the most gorgeously coloured of all animals.” The over 360 described species are primarily found in tropical and subtropical waters, as members of coral reef communities, specifically associated with their sponge prey. The chromodorids are the most speciose family of opisthobranchs. They range in size from <10mm to over 30 cm, although most species are approximately 15–30 mm in size.
Grania is a genus of marine annelid worms in the class Clitellata. They are found at many depths in sands throughout the world. They are generally about 2 centimetres (0.79 in) in length and mostly colorless or white, though Grania colorata, a recently discovered species found in the Great Barrier Reef, is green.
Leeches are segmented parasitic or predatory worms that comprise the subclass Hirudinea within the phylum Annelida. They are closely related to the oligochaetes, which include the earthworm, and like them have soft, muscular segmented bodies that can lengthen and contract. Both groups are hermaphrodites and have a clitellum, but leeches typically differ from the oligochaetes in having suckers at both ends and in having ring markings that do not correspond with their internal segmentation. The body is muscular and relatively solid, and the coelom, the spacious body cavity found in other annelids, is reduced to small channels.
Hesionidae are a family of phyllodocid "bristle worms". They are marine organisms. Most are found on the continental shelf; Hesiocaeca methanicola is found on methane ice, where it feeds on bacterial biofilms.
Rhodomelaceae is estimated to be the largest red algae family, with about 125 genera and over 700 species.
Pandalus montagui is a species of cold-water shrimp in the family Pandalidae. It is the type species of the genus Pandalus and is variously known as the pink shrimp, Aesop shrimp and Aesop prawn.
Gustavus Augustus Eisen was a Swedish-American polymath. He became a member of California Academy of Sciences in 1874 and a Life Member in 1883. In 1893, he became the 'Curator of Archaeology, Ethnology, and Lower Animals' at the academy. He later changed titles to 'Curator of Marine Invertebrates'. In 1938, he was appointed as an 'Honorary Member', which is considered the highest honor from the academy.
Inanidrilus falcifer is a species of annelid worm. It is known from subtidal silty coral sands on the Caribbean side of Barbados, in the Atlantic Ocean.
The annelids, also known as the segmented worms, are a large phylum, with over 22,000 extant species including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments.
Limnodriloides is a genus of clitellate oligochaete worms.
Globulidrilus is a genus of annelids belonging to the family Enchytraeidae.
