| Cerianthus lloydii | |
|---|---|
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Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Cnidaria |
| Subclass: | Ceriantharia |
| Order: | Spirularia |
| Family: | Cerianthidae |
| Genus: | Cerianthus |
| Species: | C. lloydii |
| Binomial name | |
| Cerianthus lloydii | |
| Synonyms [1] | |
List
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Cerianthus lloydii is a species of tube-dwelling sea anemone in the family Cerianthidae. It is sometimes called the lesser cylinder anemone and is found in shallow seas around the coasts of north west Europe.
Cerianthus lloydii was first described by the English naturalist Philip Henry Gosse in 1859. The American zoologist Henry Weed Fowler in 1897 used the name Synarachnactis bournei to describe a juvenile anemone that he had discovered. It was later established that this was in fact the larval stage of C. lloydii. Consequently, the name S. bournei was disallowed and is now considered a junior synonym of C. lloydii. [2]
Cerianthus lloydii grows to about 15 cm (6 in) long. It does not have a pedal disc with which to attach itself to the substrate but instead lives in a flexible parchment-like tube up to 40 cm (16 in) long. [3] This is buried in sand or mud with one end above the surface. Sand grains, debris and shell fragments usually stick to the outer side of the tube and the anemone extends its tentacles above the sediment to feed. The anemone can move freely within the tube and has powerful longitudinal muscles in its column which enable it to retreat swiftly into the tube. Unlike Actiniaria anemones, the tentacles themselves are unable to retract into the column. There are about seventy long, slender, tapering tentacles in an outer ring. These can span about 7 centimetres (2.8 in) when fully extended. [4] The inner ring of tentacles are short and surround the central mouth. They are used to manipulate food particles and push them into the mouth. The general colour of the anemone is pale brown and the tentacles are varying shades of brown, green or cream, often striped with darker brown. [3] [5]
Cerianthus lloydii might be confused with a less common species of anemone, Pachycerianthus multiplicatus , but this is rather larger and has about two hundred long outer tentacles giving it a feathery appearance. [4]
Cerianthus lloydii is found in the north east Atlantic Ocean from low water mark down to about 100 metres (330 ft). The range extends from Greenland and the Barents Sea to the Bay of Biscay. This anemone is locally common round the coasts of Britain except for eastern England between the River Tees and the Wash. [5] It is usually found buried in sand, gravel or mud but sometimes inhabits crevices in the rock. [6]
Cerianthus lloydii burrows by arching itself up and inserting its narrow foot into the sediment. Alternate expansions and contractions of the muscles in its body wall enable it to dig its way deeper until only the tentacles project. The fibrous burrow wall is composed of discharged nematocysts and adherent sand. [6] As sedimentation occurs, the tube is lengthened upwards, and may develop disproportionally to the size of the animal; one tube was measured as being a metre long. In extreme cases of sedimentation, when it is in danger of being swamped, the animal can eject itself from its tube, move to a more suitable location and secrete a new tube. [7]
Cerianthus lloydii feeds on zooplankton and small crustaceans that come within reach of its tentacles. It is also a scavenger and in the aquarium can be fed on fragments of meat. [6] Although it reacts fast to threats by retreating into its tube, the lemon sole (Microstomus kitt) is one of several species of fish that feed on it and other sea anemones. [8]
Spawning in Cerianthus lloydii takes place between January and August. The eggs hatch into planula larvae which remain planktonic for about four months. They are at first oval but pass through several stages, becoming more elongated and developing 9 to 11 stumpy marginal tentacles before they settle on the sea bed. [2] There is no medusa stage. Asexual reproduction by budding sometimes takes place. [6]
The starlet sea anemone is a species of small sea anemone in the family Edwardsiidae native to the east coast of the United States, with introduced populations along the coast of southeast England and the west coast of the United States. Populations have also been located in Nova Scotia, Canada. This sea anemone is found in the shallow brackish water of coastal lagoons and salt marshes where its slender column is usually buried in the mud and its tentacles exposed. Its genome has been sequenced and it is cultivated in the laboratory as a model organism, but the IUCN has listed it as being a "Vulnerable species" in the wild.
Sea anemones are a group of predatory marine invertebrates constituting the order Actiniaria. Because of their colourful appearance, they are named after the Anemone, a terrestrial flowering plant. Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Hexacorallia. As cnidarians, sea anemones are related to corals, jellyfish, tube-dwelling anemones, and Hydra. Unlike jellyfish, sea anemones do not have a medusa stage in their life cycle.
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.
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.
Sagartia troglodytes is a species of sea anemone in the family Sagartiidae, also known as the mud sagartia or the cave-dwelling anemone.
Peachia is a genus of sea anemone in the family Haloclavidae. Members of this genus typically burrow into soft substrates. The only part of the animal that is normally visible is the oral disc and tentacles which lie flat on the sand in a star shape. The type species is Peachia cylindrica.
Cerianthus is a genus of tube-dwelling anemones in the family Cerianthidae. Members of the genus are found worldwide. They are predators, scavengers and omnivores.
The burrowing anemone is a species of tube-dwelling anemone in the family Cerianthidae.
Cerianthus filiformis is a species of tube-dwelling sea anemone in the family Cerianthidae. It is found throughout the tropical waters of the western Indo-Pacific Ocean.
Cerianthus membranaceus, the cylinder anemone or coloured tube anemone, is a species of large, tube-dwelling anemone in the family Cerianthidae. It is native to the Mediterranean Sea and adjoining parts of the northeastern Atlantic Ocean.
Phoronis australis is a species of marine horseshoe worm in the phylum Phoronida. It is found in shallow warm-temperate and tropical waters in the eastern Atlantic Ocean and the Indo-Pacific region and was first detected in the Mediterranean Sea in the late twentieth century. These worms live in association with tube-dwelling anemones, particularly those in the genus Cerianthus.
Ceriantheomorphe brasiliensis is a species of tube-dwelling anemones in the family Cerianthidae. It is found in the tropical western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico. It is currently listed as endangered based on a lack of evidence.
Ceriantheopsis americana is a species of tube-dwelling anemone in the family Cerianthidae. It is a burrowing species and lives in deep sand or muddy sand in a long slender tube that it creates.
Arachnanthus sarsi is a species of tube-dwelling anemone in the family Arachnactidae. This species is found in the North Atlantic in subtidal sand or muddy sand at depths of 15–130 m.
Haloclava producta is a species of sea anemone in the family Haloclavidae, commonly known as the ghost anemone. This species is native to shallow water in the northwestern Atlantic Ocean, between Cape Hatteras and the Bay of Fundy, where it makes a temporary burrow in soft sediment. It is found on sand flats, both intertidally and subtidally.
Paranthus rapiformis, the onion anemone, is a species of sea anemone in the family Actinostolidae. It was first described by the French naturalist Charles Alexandre Lesueur in 1817 and is native to the northwestern Atlantic Ocean and the Gulf of Mexico.
Mesacmaea mitchellii is a species of sea anemone in the family Haloclavidae. It is found in the northeastern Atlantic Ocean and the Mediterranean Sea where it burrows in soft sediment.
Edwardsia neozelanica, commonly known as the burrowing anemone, is a small cryptic sea anemone from New Zealand. It burrows into soft mud or sand, and when covered with water extends its tentacles to feed on tiny particles of detritus.
Paraleptopentacta elongata is a species of sea cucumber in the family Cucumariidae. It is found in the northeastern Atlantic Ocean and parts of the Mediterranean Sea. It is an infaunal species, occupying a burrow in the seabed, from which its anterior and posterior ends project.
Thyone roscovita is a species of sea cucumber in the family Phyllophoridae. It is found on gravel, sand and mud substrates in the north-eastern Atlantic Ocean and the Mediterranean Sea at depths down to about 40 m (130 ft). It is a suspension feeder and catches food particles floating past with its branched feeding tentacles.