Double-toothed sea fir (Obelia bidentata)
Distribution data supplied by the Ocean Biodiversity Information System (OBIS). To interrogate UK data visit the NBN Atlas.Map Help
Researched by | Emily Wilson | Refereed by | Admin |
Authority | Clark, 1875 | ||
Other common names | Double-toothed hydroid | Synonyms | - |
Summary
Description
A colonial hydroid comprising erect, slightly zigzag but slender main stems that grow up to about 15 cm. The lateral branches tend to be in pairs, successively on opposite sides of the stem. The minor branches are delicate. The hydrothecae, a supporting, nonliving, protein-chitinous envelope surrounding the stem, is elongate and bell-shaped.
Recorded distribution in Britain and Ireland
Around British Isles from the Wash to near Portsmouth.Global distribution
-Habitat
Found on inert substrata such as wood, shells, wrecks and on sandy bottoms, sometimes algae. Tolerant of brackish water, sublittoral to at least 200 m, rarely intertidal in pools. Also stranded.Depth range
-Identifying features
- Colony comprising erect, polysiphonic, slender main stems.
- Lateral branches in pairs, successively on opposite sides of stem.
- Minor branches delicate, with downward curvature in life, pinnate; branchlets alternate, monosiphonic, flexuose, bearing hydrothecal pedicels at nodes.
- Hydrothecae rim with 10-20 cusps, usually bimucronate.
- Gonotheca long-obconical with slightly raised aperture.
Additional information
No text entered
Listed by
- none -
Bibliography
Hayward, P.J. & Ryland, J.S. (ed.) 1995b. Handbook of the marine fauna of North-West Europe. Oxford: Oxford University Press.
Howson, C.M. & Picton, B.E., 1997. The species directory of the marine fauna and flora of the British Isles and surrounding seas. Belfast: Ulster Museum. [Ulster Museum publication, no. 276.]
Datasets
NBN (National Biodiversity Network) Atlas. Available from: https://www.nbnatlas.org.
OBIS (Ocean Biodiversity Information System), 2024. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. www.iobis.org. Accessed: 2024-12-09
Citation
This review can be cited as:
Last Updated: 17/07/2002