Urticina lofotensis
Encyclopedia
Urticina lofotensis is a species
of sea anemone
in the family
Actiniidae
. It is commonly known as the white-spotted rose anemone or strawberry anemone.
of Urticina eques. This is not accepted by the World Register of Marine Species nor the Encyclopedia of Life.
. In California, female ripeness occurs in December as the sea temperature begins to fall. The large eggs, 1200 µm (0.047244094488189 in) in diameter, are produced at intervals, and the release of sperm by the males follows shortly afterwards. In some females, large oocyte
s also release eggs at other times of year. The gamete
s emerge through the mouth of the anemone and fertilisation is external. The eggs develop into planula
larva
e which drift with the current before settling and growing into new individuals.
(Oxylebius pictus), a species of fish, have a facultative association with Urticina lofotensis. They are often found among the tentacles or close to the column, especially when resting and inactive at night. According to researcher Joel Elliot, these associations occurred mainly in moderately exposed locations where the sea anemones and fish were both numerous; the large anemone offers the fish protection from predators
and provides a safe environment for it to feed on copepod
s and other small invertebrate
s that are also associated with the anemone. The research indicated that the fish seemed to be unharmed by the anemone's nematocysts. The anemones themselves were thought not to derive any benefits from the arrangement.
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...
in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Actiniidae
Actiniidae
The Actiniidae is the largest family of sea anemones, to which most common, temperate, shore species belong. Most members of this family do not participate in symbioses with fishes. One exception is the so-called bubble anemone - Entacmaea quadricolor....
. It is commonly known as the white-spotted rose anemone or strawberry anemone.
Taxonomy
According to one authority, the populations of Urticina lofotensis found in the Pacific Ocean are not the same species as those in the Atlantic Ocean. They are considered to be conspecific with Cribrinopsis albopunctata, a new species from Kamchatka. The same authority considers that the name Urticina lofotensis is invalid for the species found in European waters and is a junior synonymSynonym
Synonyms are different words with almost identical or similar meanings. Words that are synonyms are said to be synonymous, and the state of being a synonym is called synonymy. The word comes from Ancient Greek syn and onoma . The words car and automobile are synonyms...
of Urticina eques. This is not accepted by the World Register of Marine Species nor the Encyclopedia of Life.
Description
Urticina lofotensis has a smooth, red column with vertical rows of white tubercles. In contrast to other similar species, the tubercles are not adhesive and do not normally attract gravel and shell fragments. There are no acontia with stinging nematocysts protruding through the body wall. The oral disk is plain red and the tapering tentacles are red and have no transverse striations. This is a large sea anemone with a diameter of up to 10 cm (4 in) and 15 cm (6 in) length.Distribution and habitat
Urticina lofotensis is found in the North Atlantic Ocean and the Pacific coast of North America. It occurs between low water mark and a depth of about 15 m (49 ft). It is found on rocks and pilings, in crevices and gullies and favours exposed habitats with fast moving water.Biology
Urticina lofotensis is dioeciousDioecious
Dioecy is the property of a group of biological organisms that have males and females, but not members that have organs of both sexes at the same time. I.e., those whose individual members can usually produce only one type of gamete; each individual organism is thus distinctly female or male...
. In California, female ripeness occurs in December as the sea temperature begins to fall. The large eggs, 1200 µm (0.047244094488189 in) in diameter, are produced at intervals, and the release of sperm by the males follows shortly afterwards. In some females, large oocyte
Oocyte
An oocyte, ovocyte, or rarely ocyte, is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell which undergoes a mitotic...
s also release eggs at other times of year. The gamete
Gamete
A gamete is a cell that fuses with another cell during fertilization in organisms that reproduce sexually...
s emerge through the mouth of the anemone and fertilisation is external. The eggs develop into 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...
larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e which drift with the current before settling and growing into new individuals.
Ecology
Juveniles of the painted greenlingPainted greenling
The painted greenling, Oxylebius pictus, is a marine fish native to the eastern Pacific Ocean. Its range is from Kodiak Island, Alaska to central Baja California. It can reach a total size of 25 cm and has seven vertical dark bands. It inhabits rocky areas usually shallower than 50 m. It feeds on...
(Oxylebius pictus), a species of fish, have a facultative association with Urticina lofotensis. They are often found among the tentacles or close to the column, especially when resting and inactive at night. According to researcher Joel Elliot, these associations occurred mainly in moderately exposed locations where the sea anemones and fish were both numerous; the large anemone offers the fish protection from predators
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
and provides a safe environment for it to feed on copepod
Copepod
Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. Some species are planktonic , some are benthic , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests,...
s and other small invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s that are also associated with the anemone. The research indicated that the fish seemed to be unharmed by the anemone's nematocysts. The anemones themselves were thought not to derive any benefits from the arrangement.