Sternaspidae | |
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Scientific classification ![]() | |
Kingdom: | Animalia |
Phylum: | Annelida |
Class: | Polychaeta |
Order: | Terebellida |
Family: | Sternaspidae Carus, 1863 [1] |
Genera | |
See text |
Sternaspidae, commonly known as mud owls, [2] are a family of marine polychaete worms with short swollen bodies. They have a global distribution and live buried in soft sediment at depths varying from the intertidal zone to 4,400 m (14,400 ft). [2]
Members of this family have oval or dumbbell-shaped bodies with a small number of segments, the prostomium often being separated from the rest of the body by a narrower segment. The peristomium is reduced to lips. The first segment of the prostomium, bears the mouth but no antennae, palps or nuchal organ. The first three segments bear rows of chaetae (bristles) and the next seven segments bear lateral bundles of tiny chaetae. The parapodia present on each segment are biramous except for those near the posterior end of the body which are uniramous. On the ventral side of the posterior of the body there are two chitinised calcareous plates forming a shield, the margins of which are rimmed with bundles of capillary chaetae. A number of long, semi-coiled, thread-like gills arise from the base of the shield. The deep yellow or reddish hard shield distinguishes members of this family from other worm groups. [3] [4]
This worm lives submerged, head-down in the sediment, with its thread-like gills on the surface, presumably to facilitate oxygen take-up. It is a deposit feeder and the pharynx is eversible. It is presumed that the worm scoops up dollops of sediment with the pharynx and then extracts the nutrients from what is swallowed as the main bulk passes through the long, coiled gut. [3]
The World Register of Marine Species lists the following genera:- [1]
Polychaeta is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. More than 10,000 species are described in this class. Common representatives include the lugworm and the sandworm or clam worm Alitta.
Oligochaeta is a subclass of 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.
In invertebrates, the term parapodium refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed lateral outgrowths that bear the chaetae. In several groups of sea snails and sea slugs, 'parapodium' refers to lateral fleshy protrusions.
Glyceridae is a family of polychaete worms. They are commonly referred to as beak-thrower worms or bloodworms. They are bright red, segmented, aquatic worms. The proboscis worm Glycera is sometimes called bloodworm. The Glyceridae are ferocious epi- and infaunal polychaetes that prey upon small invertebrates. They are errant burrowers that build galleries of interconnected tubes to aid in catching their prey.
Eunicida is an order of polychaete worms.
Phyllodocida is an order of polychaete worms in the subclass Aciculata. These worms are mostly marine though some are found in brackish water. Most are active benthic creatures, moving over the surface or burrowing in sediments, or living in cracks and crevices in bedrock. A few construct tubes in which they live and some are pelagic, swimming through the water column. There are estimated to be about 3,500 species in the order.
Cirratulus cirratus is a species of marine polychaete worm in the family Cirratulidae. It occurs in the littoral and sub-littoral zones of the Atlantic Ocean.
Lanice conchilega, commonly known as the sand mason worm, is a species of burrowing marine polychaete worm. It builds a characteristic tube which projects from the seabed, consisting of cemented sand grains and shell fragments with a fringe at the top.
Abarenicola pacifica or the Pacific lugworm is a large species of polychaete worm found on the west coast of North America and also in Japan. The worms live out of sight in burrows under the sand and produce casts which are visible on the surface.
Lagis koreni, commonly known as the trumpet worm, is a species of marine polychaete worm found in European waters. It lives within a narrow conical tube made of grains of sand and shell fragments.
Spionida is an order of marine polychaete worms in the infraclass Canalipalpata. Spionids are cosmopolitan and live in soft substrates in the littoral or neritic zones.
Scalibregma inflatum, also known as T headed worm, is a burrowing marine polychaete. It is a cosmopolitan species that can be found from the Arctic to Antarctica, although most probably several species are confounded.
Prosphaerosyllis battiri is a species belonging to the phylum Annelida, a group known as the segmented worms. The species name comes from an Aboriginal word, battiri, meaning "rough". Prosphaerosyllis battiri is a species characterized by having only partially fused palps, an unretracted prostomium on its peristomium or showing only slight retraction, the shape of its dorsal cirri and its arrangement of papillae, being numerous anteriorly while less numerous posteriorly. It resembles Prosphaerosyllis semiverrucosa, but its arrangement of dorsal papillae is reversed.
Ophryotrocha craigsmithi is a species of polychaete worm. O. craigsmithi is named after Craig R. Smith. This species is similar to Palpiphitime lipovskyae and O. Platykephale, among others, in having branchial structures dorsally and ventrally. It differs from O. platykephale in the shape of its prostomium and parapodia. Palpiphitime lipovskyae has jaws of both P- and K-type, while no specimens of O. craigsmithi have been found with K-type jaws thus far. Ophryotrocha craigsmithi differs from P. lipovskyae genetically, but also by the presence of a prominent ventral chaetal lobe with a bulging simple chaeta in the former.
Phyllodoce maculata is a species of Polychaete worm in the family Phyllodocidae. It is native to the northeastern Atlantic Ocean where it inhabits shallow water areas of sand, mud and stones.
Phyllodocidae is a family of polychaete worms. Worms in this family live on the seabed and may burrow under the sediment.
Scolelepis squamata is a species of polychaete worm in the family Spionidae. It occurs on the lower shore of coasts on either side of the Atlantic Ocean.
Lepidasthenia is a genus of marine Polychaete worms belonging to the family Polynoidae. Species of Lepidasthenia are found world-wide to depths of about 1200 m but are more common in shallower water.
Poecilochaetus serpens is a species of marine polychaete worm in the family Poecilochaetidae. It is a benthic worm that burrows into soft sediment.
Sternaspis scutata is a species of marine polychaete worm in the family Sternaspidae. It occurs in the Mediterranean Sea and the temperate northeastern Atlantic Ocean. It lives submerged in mud or other soft sediment.