Also found in: Dictionary, Thesaurus, Medical, Wikipedia.


see ChordataChordata
, phylum of animals having a notochord, or dorsal stiffening rod, as the chief internal skeletal support at some stage of their development. Most chordates are vertebrates (animals with backbones), but the phylum also includes some small marine invertebrate animals.
..... Click the link for more information.
; tunicatetunicate
, marine animal of the phylum Chordata, which also includes the vertebrates. The adult form of most tunicates (also called urochordates) shows no resemblance to vertebrate animals, but such a resemblance is evident in the larva.
..... Click the link for more information.
References in periodicals archive ?
BotryUoides leachii is a sessile suspension-feeding ascidian that lives in clonal colonies of adults, termed zooids, that organize in a series of ladder-like parallel rows, known as systems (Fig.
Ultrastructure of vegetative and sporulation tages of Haplosporidium ascidiarum from the Ascidian Ciona intestinalis L.
To understand how maternal factors in ascidian eggs establish the initial state of the gene regulatory network, we need to understand how the four main maternal factors (along with other currently unknown factors, if any) induce these nine distinct patterns of gene expression.
This interpretation is in accordance with our data, since the lowest concentrations of P were found in the ascidian P.
ISHII (1990): <<Primary structure of ascidian trypsin inhibitors in the hemolymph of a solitary asci dian Halocynthia roretzi>>, Journal of Biochemistry, vol.
Chemical control of bacterial epibiosis on ascidians.
Thus, locales with high ascidian populations hold great potential for scientific and commercial research.
Often, a pair lives within the mantle cavity or branchial region of their host, which is a mollusk or ascidian.
These zones were characterized by a mussel-dominated assemblage at [approximately] 3 m; a hydroid and bryozoan dominated assemblage at [approximately] 5 m; a sponge, bryozoan, and ascidian dominated assemblage at [approximately] 10 m; and a deeper assemblage of sponges, bryozoans, brachiopods, and ascidians at [approximately] 18 m depth (Witman and Grange 1998).
Nonrandom utilization of sperm has been clearly documented in the ascidian, Diplosoma listerianum, a sessile, colonial, clonal, marine filter-feeder (Bishop 1996; Bishop et al.