Spherical snails
| Spherical snails | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name of the superfamily | ||||||||||||
| Akeroidea | ||||||||||||
| Mazzarelli , 1891 | ||||||||||||
| Scientific name of the family | ||||||||||||
| Akeridae | ||||||||||||
| Mazzarelli , 1891 | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Akera | ||||||||||||
| OV Müller , 1776 |
The spherical snails ( Akera ) are a genus and family of mostly medium-sized marine shell -bearing snails in the order of the broad- footed snails (Anaspidea) that occur in all oceans . Akera is the only genus in the Akeridae family . It comprises five recognized species.
features
The spherical snails carry a thin-walled, oval snail shell with several passageways on their back , which cannot completely accommodate the snail's body. The head shield is provided with inconspicuous, round, wing-like extensions. The snails have large parapodia on both sides of their feet, which meet above the shell and with the help of which the snails can swim. The mantle cavity contains a gill . The snails have a gizzard with numerous plates. The radula is multi-row with a central tooth and several posterior teeth on both sides.
The snails are hermaphrodites that mate in rows. Ribbon -like clutches with numerous eggs are deposited from which Veliger larvae hatch, which after a pelagic phase metamorphose into juvenile snails .
The ball snails feed mainly on green algae , but also red algae . But they are at least partially able to eat seaweed ( Zostera ).
distribution
Ball snails live mainly on sandy grounds and in sea grass meadows . You can find them in seas around the world.
Systematics
According to Bouchet and Rocroi (2005), the Akeridae family forms, alongside the Aplysiidae, one of two families in the suborder Aplysiomorpha . The Akeridae family includes five species:
- Akera bayeri Ev. Marcus & He. Marcus, 1967 ( Synonym : Akera thompsoni Olsson & McGinty, 1951, nomen nudum)
- Akera bullata OF Müller, 1776 ( type species )
- Akera julieae Valdés & Barwick, 2005
- Akera silbo Ortea & Moro, 2009
- Akera soluta (Gmelin, 1791)
literature
- TE Thompson: Molluscs: Benthic Opisthobranchs (Mollusca: Gastropoda). Keys and Notes for the Identification of the Species . EJ Brill Academic Pub for the Linnean Society, London 1989. 356 pp.
- Philippe Bouchet & Jean-Pierre Rocroi: Part 2. Working classification of the Gastropoda . Malacologia, 47: 239-283, Ann Arbor 2005 ISSN 0076-2997