Protanthea simplex
Encyclopedia
Protanthea simplex is a species
of sea anemone
found in deep water off the coasts of north west Europe.
s are non-retractable and have a frosty appearance and are usually held outstretched. The column is salmon pink, flared below the tentacles and reaches lengths of up to two centimetres. It has a flattened, lightly adherent base bulging out below the pedal disc. There are up to 200 slender, translucent, white or pale pink tentacles up to one and a half centimetres long arranged in five rings. When the orangeish-pink gonads are ripe, they may be visible through the wall of the column.
northward, particularly in sea lochs. It is also found round the coasts of the Skagerrak
and northern Kattegat
and in one location in Connemara
, Galway
, Ireland. It seems to prefer vertical rock faces in sheltered sites with little movement of water and has been found as deep as five hundred metres.
and hangs limply from its pedal disc attachment. At other times it is very active, exhibiting a violent thrashing of the tentacles in response to external stimuli.
Reproduction can be by sexual or asexual means. In sexual reproduction, eggs and sperm are ejected through the mouth and liberated into the sea. The fertilised egg develops into a planula
, which settles after fifteen to twenty days and grows into a new individual. In asexual reproduction
, fragments of the column are capable of regenerating into new individuals.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of sea anemone
Sea anemone
Sea anemones are a group of water-dwelling, predatory animals of the order Actiniaria; they are named after the anemone, a terrestrial flower. Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Zoantharia. Anthozoa often have large polyps that allow for digestion of larger...
found in deep water off the coasts of north west Europe.
Description
P. simplex is a delicate sea anemone. The tentacleTentacle
A tentacle or bothrium is one of usually two or more elongated flexible organs present in animals, especially invertebrates. The term may also refer to the hairs of the leaves of some insectivorous plants. Usually, tentacles are used for feeding, feeling and grasping. Anatomically, they work like...
s are non-retractable and have a frosty appearance and are usually held outstretched. The column is salmon pink, flared below the tentacles and reaches lengths of up to two centimetres. It has a flattened, lightly adherent base bulging out below the pedal disc. There are up to 200 slender, translucent, white or pale pink tentacles up to one and a half centimetres long arranged in five rings. When the orangeish-pink gonads are ripe, they may be visible through the wall of the column.
Distribution
This species is found in both shallow and deep water around the western coast of Scotland from the Firth of ClydeFirth of Clyde
The Firth of Clyde forms a large area of coastal water, sheltered from the Atlantic Ocean by the Kintyre peninsula which encloses the outer firth in Argyll and Ayrshire, Scotland. The Kilbrannan Sound is a large arm of the Firth of Clyde, separating the Kintyre Peninsula from the Isle of Arran.At...
northward, particularly in sea lochs. It is also found round the coasts of the Skagerrak
Skagerrak
The Skagerrak is a strait running between Norway and the southwest coast of Sweden and the Jutland peninsula of Denmark, connecting the North Sea and the Kattegat sea area, which leads to the Baltic Sea.-Name:...
and northern Kattegat
Kattegat
The Kattegat , or Kattegatt is a sea area bounded by the Jutland peninsula and the Straits islands of Denmark on the west and south, and the provinces of Västergötland, Scania, Halland and Bohuslän in Sweden on the east. The Baltic Sea drains into the Kattegat through the Øresund and the Danish...
and in one location in Connemara
Connemara
Connemara is a district in the west of Ireland consisting of a broad peninsula between Killary Harbour and Kilkieran Bay in the west of County Galway.-Overview:...
, Galway
Galway
Galway or City of Galway is a city in County Galway, Republic of Ireland. It is the sixth largest and the fastest-growing city in Ireland. It is also the third largest city within the Republic and the only city in the Province of Connacht. Located on the west coast of Ireland, it sits on the...
, Ireland. It seems to prefer vertical rock faces in sheltered sites with little movement of water and has been found as deep as five hundred metres.
Biology
This species is a passive suspension feeder. It is often solitary but it has been recorded at densities of up to two thousand per square metre. It shows an unusual behaviour when occasionally it loses muscle toneMuscle tone
In physiology, medicine, and anatomy, muscle tone is the continuous and passive partial contraction of the muscles, or the muscle’s resistance to passive stretch during resting state. It helps maintain posture, and it declines during REM sleep.-Purpose:Unconscious nerve impulses maintain the...
and hangs limply from its pedal disc attachment. At other times it is very active, exhibiting a violent thrashing of the tentacles in response to external stimuli.
Reproduction can be by sexual or asexual means. In sexual reproduction, eggs and sperm are ejected through the mouth and liberated into the sea. The fertilised egg develops into a planula
Planula
A planula is the free-swimming, flattened, ciliated, bilaterally symmetric larval form of various cnidarian species. The planula forms from the fertilized egg of a medusa, as the case in scyphozoans and some hydrozoans, or from a polyp, as in the case of anthozoans...
, which settles after fifteen to twenty days and grows into a new individual. In asexual reproduction
Asexual reproduction
Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only, it is reproduction which does not involve meiosis, ploidy reduction, or fertilization. A more stringent definition is agamogenesis which is reproduction without...
, fragments of the column are capable of regenerating into new individuals.