| Sagartia troglodytes | |
|---|---|
 | |
| Several species of Sagartia . S. troglodytes is at top right. | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Cnidaria |
| Class: | Hexacorallia |
| Order: | Actiniaria |
| Family: | Sagartiidae |
| Genus: | Sagartia |
| Species: | S. troglodytes |
| Binomial name | |
| Sagartia troglodytes | |
| Synonyms | |
List
| |
Sagartia troglodytes is a species of sea anemone in the family Sagartiidae, also known as the mud sagartia or the cave-dwelling anemone.
The base is anchored in holes in the rock and is a little wider than the column. This is smooth and firm, extending to a length several times its width, and covered in sticky suckers on its upper part. The usually flat oral disc is finely patterned and surrounded by four or five rings of numerous short tentacles, the longest ones being nearest the mouth. This is raised on a slight mound at the centre of the disc. The general colour is varying sombre shade of olive green or brown with vertical striations on the column. The radial striations on the oral disc are finely patterned in grey, white and black and the tentacles are translucent and banded in white and grey. At the base of each tentacle there is a distinctive black mark shaped like a Roman capital letter "B". [2] Pieces of gravel and fragments of shell are often stuck to the upper part of the column. In size, the column can grow to a diameter of an inch (2.5 cm) and a length of two inches (5 cm) but most specimens are much smaller than this. [3]
S. troglodytes is found in coastal regions of the north east Atlantic Ocean, the North Sea and the Mediterranean Sea. [1] It is common round the coasts of Britain between the tide marks but is relatively little observed because it is well camouflaged and is often hidden in cracks, under overhangs, in rock pools, under seaweed, among mussels or half buried in sand and mud with just its tentacles projecting. [3] In Morecambe Bay, England, it is found anchored to stones buried several inches beneath the surface of this expanse of mudflats, or sometimes not even attached at all but living freely. It can retract into a spherical form when disturbed and no longer be visible from the surface. [2]
Like other sea anemones, S. troglodytes is a carnivore and feeds on small invertebrates which it traps with its tentacles and channels into its mouth. Any undigested pieces are expelled from the mouth over the period of a few hours or days. [2]
S. troglodytes is a hermaphrodite with gonads inside the body cavity. The eggs are discharged from the mouth, being wafted out individually by cilia on the tentacles. The sperm are produced separately also emanating from the mouth when they give the appearance of a white plume being liberated into the water column. The fertilised egg develops into a planula larva which becomes part of the zooplankton and later settles and develops into a new individual. The species can also reproduce asexually by the liberation of "ciliated germs" through the walls of the lower column. [2]
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.
Urticina crassicornis, commonly known as the mottled anemone, the painted anemone or the Christmas anemone, is a large and common intertidal and subtidal sea anemone. Its habitat includes a large portion of the coastal areas of the northern hemisphere, mainly polar regions, and it lives a solitary life for up to 80 years. Mottled anemones are similar to Dahlia anemones and both are commonly referred to as northern red anemones.
Sea anemones are a group of predatory marine invertebrates of 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.
Sagartia ichthystoma is a species of sea anemone in the family Sagartiidae, also known as the fish-mouth anemone. The species name refers to the short pointed tentacles round the edge of the disc which resemble the sharp teeth of certain fish.
Metridium senile, or frilled anemone, is a species of sea anemone in the family Metridiidae. As a member of the genus Metridium, it is a type of plumose anemone and is found in the seas off north-western Europe and both the east and west coasts of North America.
Sagartia elegans, the elegant anemone, is a species of sea anemone in the family Sagartiidae. It is found in coastal areas of northwest Europe at depths down to 50 metres.
Calliactis polypus is a species of sea anemone in the family Hormathiidae. It is usually found living on the surface of a sea snail shell in which a hermit crab is living.
Peachia cylindrica is a large species of sea anemone in the family Haloclavidae. It is normally found burrowed into soft substrates, the only visible part of the animal being the oral disc and tentacles which usually lie flat on the sand. It is the type species of the genus Peachia.
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.
Macrodactyla doreensis, common names long tentacle anemone and corkscrew tentacle sea anemone, is a species of sea anemone in the family Actiniidae.
Dofleinia armata, commonly known as the striped anemone or armed anemone, is a species of sea anemone in the family Actiniidae. It is the only species in the genus Dofleinia.
Aeolidiella alderi is a species of sea slug, an aeolid nudibranch in the family Aeolidiidae. It is native to northwestern Europe where it occurs in the intertidal zone. It is a predator and feeds on sea anemones.
Diadumene cincta is a small and delicate, usually orange, sea anemone. It has a smooth slender column and up to 200 long tentacles, and normally grows to a length of up to 35 mm (1.4 in), with a base of 10 mm (0.4 in), but specimens twice this size have been recorded. Diadumene cincta is found in the northeastern Atlantic Ocean.
Actinothoe sphyrodeta, the sandalled anemone, is a small sea anemone in the family Sagartiidae. It is native to the northeastern Atlantic Ocean and is common on the north, west and south coasts of Britain. It is usually grey or whitish but may have an orange oral disc. The translucent white tentacles that grow around the edge of the oral disc can number up to 120.
Epiactis lisbethae, commonly known as Lisbeth's brooding anemone, is a species of sea anemone in the family Actiniidae. It is similar in appearance to the common brooding anemone, and like it is native to shallow waters on the western coast of North America.
Epiactis fernaldi, commonly known as the Fernald brooding anemone, is a species of sea anemone in the family Actiniidae. It is native to shallow waters around the San Juan Islands off the western coast of North America.
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.
Anthopleura artemisia is a species of sea anemone. It is known by a number of common names, including burrowing anemone and moonglow anemone. It was first described to science in 1846 in a volume by James Dwight Dana, reporting on the animals found on the United States Exploring Expedition. Dana attributes the description to Charles Pickering, who was a naturalist on the expedition.
Actinostella flosculifera, the collared sand anemone, is a species of sea anemone in the family Actiniidae. It is found semi-immersed in the sediment in shallow water in the tropical and subtropical Atlantic Ocean.