''Ciona'' is a genus of
sea squirts
Ascidiacea, commonly known as the ascidians, tunicates (in part), and sea squirts (in part), is a polyphyletic class (biology), class in the subphylum Tunicate, Tunicata of sac-like marine (ocean), marine invertebrate filter feeders. Ascidians ar ...
in the family
Cionidae.
The body of ''Ciona'' is bag-like and covered by a
tunic, which is a secretion of the
epidermal cells. The body is attached at a permanent base located at the posterior part, and the opposite bears two openings, the
buccal (
oral) and
atrial (
cloaca
In animal anatomy, a cloaca ( ), plural cloacae ( or ), is the posterior orifice that serves as the only opening for the digestive, reproductive, and urinary tracts (if present) of many vertebrate animals. All amphibians, reptiles and birds, a ...
l)
siphon
A siphon (from grc, σίφων, síphōn, "pipe, tube", also spelled nonetymologically syphon) is any of a wide variety of devices that involve the flow of liquids through tubes. In a narrower sense, the word refers particularly to a tube in a ...
s. The water is drawn into the
ascidian through the buccal siphon and leaves the
atrium through the atrial siphon.
Species
Species in this genus include:
* ''
Ciona antarctica
''Ciona'' is a genus of sea squirts in the family Cionidae.
The body of ''Ciona'' is bag-like and covered by a tunic, which is a secretion of the epidermal cells. The body is attached at a permanent base located at the posterior part, and the ...
''
* ''
Ciona edwardsi''
* ''
Ciona fascicularis
''Ciona'' is a genus of sea squirts in the family Cionidae.
The body of ''Ciona'' is bag-like and covered by a tunic, which is a secretion of the epidermal cells. The body is attached at a permanent base located at the posterior part, and the opp ...
''
* ''
Ciona gelatinosa
''Ciona'' is a genus of sea squirts in the family Cionidae.
The body of ''Ciona'' is bag-like and covered by a tunic, which is a secretion of the epidermal cells. The body is attached at a permanent base located at the posterior part, and the opp ...
''
* ''
Ciona hoshinoi''
* ''
Ciona imperfecta
''Ciona'' is a genus of sea squirts in the family Cionidae.
The body of ''Ciona'' is bag-like and covered by a tunic, which is a secretion of the epidermal cells. The body is attached at a permanent base located at the posterior part, and the opp ...
''
* ''
Ciona intermedia
''Ciona'' is a genus of sea squirts in the family Cionidae.
The body of ''Ciona'' is bag-like and covered by a tunic, which is a secretion of the epidermal cells. The body is attached at a permanent base located at the posterior part, and the opp ...
''
* ''
Ciona intestinalis
''Ciona intestinalis'' (sometimes known by the common name of vase tunicate) is an ascidian (sea squirt), a tunicate with very soft tunic. Its Latin name literally means "pillar of intestines", referring to the fact that its body is a soft, trans ...
''
* ''
Ciona longissima''
* ''
Ciona mollis''
* ''
Ciona pomponiae''
* ''
Ciona robusta''
* ''
Ciona roulei''
* ''
Ciona savignyi''
* ''
Ciona sheikoi''
Genome projects
As of 2008, the genomes of ''Ciona intestinalis''
[P. Dehal et al.: ''The draft genome of Ciona intestinalis: insights into chordate and vertebrate origins.'' Science, 298, 5601, S. 2157–67, 13. Dezember 2002] and ''Ciona savignyi''
[The C. savignyi Reference Genome and Genetic Map](_blank)
/ref> have been sequenced.
Sexual reproduction
'' C. intestinalis'' is a 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 ...
that releases sperm and eggs almost simultaneously into the surrounding seawater. ''C. intestinalis'' is self-sterile and thus has been used for studies on the mechanism of self-incompatibility.
References
External links
The Tunicate Portal
an access point to the main websites and databases dealing with tunicates
Ascidians.com
pictures of species around the world
ANISEED
a model organism database for several ascidians species including ''Ciona intestinalis'' and ''Halocynthia roretzi''
JGI Ciona intestinalis v2.0
genome sequence
*
Enterogona
Tunicate genera
{{tunicata-stub