Simnia patula
Simnia patula | ||||||||||||
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Housing of Simnia patula , from: Illustrated Index of British Shells , 1859. |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Simnia patula | ||||||||||||
( Pennant , 1777) |
Simnia patula is the name of a snail fromthe egg shell family that iswidespreadin the western Atlantic andfeeds onsessile cnidarians .
features
The thin, glossy, egg-shaped snail shell of Simnia patula has a thread that is enclosed in the perimeter of the adult animal, but is still visible in young animals with three inflated passages. The long and oval mouth of the case has two flared lips that are longer than the other parts of the shell and merge into a channel at both ends. The basal inhalation channel is much wider and less separated from the housing mouth than the apical exhalation channel. The house is up to 2 cm long and 8 mm wide in adult snails. The surface of the shell is white, yellow or pink, the body of the snail yellow with brown stripes and spots, especially on the mantle , which forms a breathing tube at its end and covers the shell with two lobes when the snail moves. The large foot has a longitudinal crest and is colored pink in front. The two long antennae on the head are white to brown tips and have a small eye at their base.
distribution and habitat
Simnia patula is widespread in the north-east of the Atlantic Ocean on the coasts of south-west England and Wales , Ireland and parts of Scotland, as well as north-west France . It lives in particular on the cnidarians it prefers as hosts , Alcyonium digitatum , Eunicella verrucosa and Tubularia indivisa , on which it feeds, at depths below the intertidal zone of around 15 to 75 m.
Life cycle
Like other egg snails, Simnia patula is of separate sex. Internal fertilization takes place. The eggs are laid in irregular, rounded clusters over 2.5 cm thick on the cnidarians that serve as hosts. The egg capsules are round to polygonal and about 3.5 mm thick. They are held together by a tough, somewhat yellowish to colorless layer. All eggs develop into Veliger larvae, which presumably live as zooplankton for many weeks before they metamorphose into snails . They can form the most common species in zooplankton in summer.
food
Simnia patula eats preferred polyp and Coenenchym nettle species Alcyonium digitatum , Eunicella verrucosa and Tubularia indivisa .
Web links
- SJ Rowley: Simnia patula - A gastropod. 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.
- Fischhaus Zepkow: Family Ovulidae - egg snails