''Dendrodoa grossularia'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

tunicate A tunicate is a marine invertebrate animal, a member of the subphylum Tunicata (). It is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords (including vertebrates). The subphylum was at one time ca ...

or sea squirt in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Styelidae Styelidae is a family of ascidian tunicates.Lambert, G.; Gittenberger, A.; Sanamyan, K. (2015)Styelidae Sluiter, 1895.In: Shenkar, N.; Gittenberger, A.; Lambert, G.; Rius, M.; Moreira Da Rocha, R.; Swalla, B.J.; Turon, X. (2015) Ascidiacea World ...

, commonly known as the baked bean ascidian. It is native to the northeastern Atlantic Ocean where it is common in shallow water and on the lower shore in exposed rocky sites.

Description

''Dendrodoa grossularia'' is sometimes known as the sea currant because of its small, red, globular form. It usually grows in aggregations, forming mats across the rock surface, but occasionally occurs as individual

zooid A zooid or zoöid is a single animal that is part of a colonial animal. This lifestyle has been adopted by animals from separate unrelated taxa. Zooids are multicellular; their structure is similar to that of other solitary animals. The zooi ...

s. When crowded together, the zooids are cylindrical, tall and half as wide. Each individual has the two circular siphons near the apex, the buccal siphon being slightly larger than the exhalent siphon. The tunic is smooth, translucent and of fairly firm consistency, and the siphons tend to be a more intense colour than the rest of the tunic. Solitary individuals are smaller, depressed and unnoticeable. The tunic often has sand or silt deposited on it and sometimes supports epibionts. This species could be confused with ''

Distomus variolosus ''Distomus variolosus'' is a species of tunicate or sea squirt in the family Styelidae. It is native to the northeastern Atlantic Ocean where it lives on the seabed,Gittenberger, A.; Sanamyan, K. (2015)''Distomus variolosus'' Gaertner, 1774.In: S ...

'' or ''

Stolonica socialis ''Stolonica socialis'' is a species of tunicate or sea squirt in the family Styelidae, commonly known as orange sea grapes. It is native to the northeastern Atlantic Ocean, where it lives on the rocky seabed in shallow water.Sanamyan, K. (2015)'' ...

''; the former is smaller, never more than tall, while the latter is a

colonial Colonial or The Colonial may refer to: * Colonial, of, relating to, or characteristic of a colony or colony (biology) Architecture * American colonial architecture * French Colonial * Spanish Colonial architecture Automobiles * Colonial (1920 a ...

species with a creeping

stolon In biology, stolons (from Latin '' stolō'', genitive ''stolōnis'' – "branch"), also known as runners, are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external s ...

, and is orange or orangish-brown.

Distribution and habitat

This species is widely distributed in the northeastern

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

.Sanamyan, K. (2015)
''Dendrodoa grossularia'' (Van Beneden, 1846).
In: Shenkar, N.; Gittenberger, A.; Lambert, G.; Rius, M.; Moreira Da Rocha, R.; Swalla, B.J.; Turon, X. (2015) Ascidiacea World Database. Accessed through: World Register of Marine Species on 2015-12-23Picton, B.E. & Morrow, C.C. (2015)
''Dendrodoa grossularia'' (van Beneden, 1846).
n/nowiki> Encyclopedia of Marine Life of Britain and Ireland. Accessed on 2015-12-23 Its range includes the Baltic Sea, the English Channel, and northwestern France as far south as

Quiberon Quiberon (; , ) is a commune in the French department of Morbihan, administrative region of Brittany, western France. It is situated on the southern part of the Quiberon peninsula, the northern part being the commune of Saint-Pierre-Quiberon. It ...

, but it is absent from some localities and has a number of sub-populations. Colonies grows on rocks and boulders in areas with strong currents, and sometimes on the holdfasts of kelp, at depths from the lower shore down to a few metres. It favours shaded rocks, boulders, ledges and overhangs, and can form large populations in suitable habitats. Single zooids may be attached to stones or mollusc shells, alive or dead. At exceptionally low tides, it may be found under overhanging rocks on the lower shore. It is tolerant of low salinities and may be found in estuaries.

Ecology

Like all tunicates, ''Dendrodoa grossularia'' is a

filter feeder Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...

, drawing water in through the buccal siphon and expelling it through the exhalent siphon. It is a non-simultaneous

hermaphrodite In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

. Sperm is emitted into the

water column A water column is a conceptual column of water from the surface of a sea, river or lake to the bottom sediment.Munson, B.H., Axler, R., Hagley C., Host G., Merrick G., Richards C. (2004).Glossary. ''Water on the Web''. University of Minnesota-D ...

and drawn into other individuals, fertilising the ova in the body cavity. The embryos are brooded here, before being liberated into the water as tadpole-like larvae. After a short

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

ic period, some settle onto the tunics of adult individuals.

References

{{Taxonbar, from=Q4918755 Stolidobranchia Animals described in 1846 Fauna of the Atlantic Ocean