Owenia fusiformis
| Owenia fusiformis | ||||||||||||
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Owenia fusiformis |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Owenia fusiformis | ||||||||||||
| Delle Chiaje , 1842 |
Owenia fusiformis is a röhrenbauender , reduced mobility, as filter feeders living polychaete (Polychaeta) serving as cosmopolitan in oceans can be found worldwide.
features
Owenia fusiformis has a rather short body, cylindrical at the front and slightly flattened at the back, which is up to 10 cm long and has about 30 segments and a greenish to yellowish color with paler glandular stripes.
The head has a tentacle crown with 6 short, membranous appendages, which are incised into numerous conspicuous lobes, and at the end a three-lobed mouth. The first three bristle-bearing segments that make up the thorax are short and only have notopodia . The following segments, usually around 15 to 20, which form the abdomen, have parapodia with notopodia and neuropodia . The last segments at the end of the body are short again. The bristles of the notopodia on the thorax are spiky capillary-like bristles and sit directly on the epidermis ; the bristles of the third bristle bundle are shorter than the others; the notopodia do not have parapodia flaps. The neuropodia of the abdomen are broad, flattened tori with many small, bidentate hooks. The bristles of the notopodia of the abdomen are similar to those on the thorax and are also located directly on the epidermis. The pygidium is covered with small, round papillae.
Residential tube
The living tube, cemented together from coarse mineral particles with the body's own mucus, is cylindrical and densely covered with grains of sand and shell fragments, whereby the pieces overlap like roof tiles.
distribution and habitat
Owenia fusiformis is widespread as a cosmopolitan in the Pacific Ocean and Indian Ocean as well as in the Atlantic Ocean including the Mediterranean and the North Sea to the Øresund . The polychaet lives in the intertidal zone and below on various surfaces, but it needs sand, gravel and pieces of shell to build its living tube. It can crawl around with its tube and thus change its location.
Development cycle
Owenia fusiformis is separate from the sexes. They live to be around 3 years old and can mate once a year. In sexually mature animals, the coelom spaces of the posterior segments are filled with gametes , which are released through two pores in the anus, so that fertilization takes place in the open sea water. A female can lay 6,000 to 85,000 eggs at once, depending on size. Within 24 hours of fertilization, a mitraria larva develops, which develops into an actively swimming trochophora larva in 2 to 3 days . The pelagic stage as zooplankton lasts about 4 months until the mature larva finds a suitable substrate, sinks to the bottom and metamorphoses into a creeping worm .
nutrition
Owenia fusiform feeds as filter feeders of detritus .
literature
- Gesa Hartmann-Schröder (1996): Annelida, Borstenwürmer, Polychaeta. Tierwelt Deutschlands 58, pp. 1–648, here p. 436, Owenia fusiformis Delle Chiaje, 1841.
- John D. Fish, Susan Fish: A Student's Guide to the Seashore . Cambridge University Press, Cambridge 2011. 540 pages. Owenia fusiformis Delle Chiaje , p. 167.
- Stanley J. Edmonds: Fauna of Australia, Volume 4A. Polychaetes & Allies. The Southern Synthesis 4. Commonwealth of Australia, 2000. Class Polychaeta. Pp. 235-138, Family Oweniidae.
Web links
- MJ de Kluijver et al .: Owenia fusiformis Delle Chiaje, 1842. Macrobenthos of the North Sea - Polychaeta, Marine Species Identification Portal
- KJ Neal, P. Avant: Owenia fusiformis Delle Chiaje, 1842. In: H. Tyler-Walters, K. Hiscock (Eds.): Marine Life Information Network, Biology and Sensitivity Key Information Reviews. Marine Biological Association of the United Kingdom, Plymouth 2008.