Lattice snails
| Lattice snails | ||||||||||||
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Housing of Trigonostoma milleri |
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| Scientific name | ||||||||||||
| Cancellariidae | ||||||||||||
| Forbes & Hanley , 1851 |
The lattice snails (Cancellariidae) are a family of rather small to medium-sized, exclusively marine snails that occur worldwide in tropical to cold seas. As far as is known, all representatives feed as temporary ectoparasites on mussels , snails and fish on blood or suck out eggs and egg capsules. About 300 species are described.
features
The right-hand winding, egg-shaped to spindle-shaped casings of the lattice worms have a thread with stepped passages. The surface of the housing is network-like to grid-shaped due to the axial and spiral sculpting. The columella usually has varices, but it can also be imperforate. The finished snails do not have an operculum , but this can be detected in the Veliger larvae.
The Cancellariidae have a long, thin proboscis in which the salivary glands are located. The highly specialized radula is located well within the proboscis directly in front of the Leiblein valve. As with the conoid , the anterior esophagus has receded. The intestinal canal is greatly simplified, which can be explained with the liquid food. The dorsal folds protrude far into the esophagus and almost to the stomach.
The animals are separate sexes with internal fertilization. The eggs are attached to the ground in egg capsules. In some of the species, plankton-eating, free-swimming Veliger larvae hatch, which later metamorphose into small snails , while in others the larval development takes place in the capsules, so that ready-made young snails hatch.
Way of life, occurrence and distribution
The Cancellariidae are widespread worldwide, mainly in tropical and subtropical, sometimes temperate to cold seas. They usually live on soft ground from the intertidal zone to depths of around 1000 meters.
The most studied to date Cancellariidae suck shells and sand-dwelling snails blood while Cancellaria cooperi this to torpedo does (O'Sullivan, McConnaughy and Huber, 1987). To do this, the snails seek out their host in its resting phase and stab it with their thin proboscis , which can be extended far beyond the body's length , in order to suckle its blood . Other species prefer eggs from various marine animals as food; For example, they suck out the egg capsules from snails.
Systematics
After Bouchet and Rocroi (2005), the family Cancellariidae simultaneously forms the superfamily Cancellarioidea within the Neogastropoda . Criterion for establishing one's own superfamily is the lack of a body gland and a poison gland. They divide the Cancellariidae family into three subfamilies: Plesiotritoninae , Admetinae and Cancellariinae .
A cladistic analysis on a molecular genetic basis by Modica, Bouchet, Cruaud, Utge, and Oliverio (2011) suggests that the subfamily Plesiotritoninae is monophyletic while the subfamily Admetinae and Cancellariinae are considered polyphyletic. The authors also see a revision of the genera Nipponaphera , Merica , Sydaphera and Bivetia as necessary.
literature
- Maria Vittoria Modica, Philippe Bouchet, Corinne Cruaud, José Utge, Marco Oliverio (2011): Molecular phylogeny of the nutmeg shells (Neogastropoda, Cancellariidae) . Molecular Phylogenetics and Evolution 59 (3), pp. 685-697.
- JB O'Sullivan, RR McConnaughey, ME Huber (1997): A blood-sucking snail: the Cooper's nutmeg, Cancellaria cooperi Gabb, parasitises the California electric ray, Torpedo californica Ayres . Biological Bulletin 172, pp. 362-366.
- Maria Vittoria Modica, Mandë Holford: The Neogastropoda: Evolutionary Innovations of Predatory Marine Snails with Remarkable Pharmacological Potential (PDF; 375 kB) . In: P. Pontarotti (Ed.): Evolutionary Biology - Concepts, Molecular and Morphological Evolution . Springer-Verlag Berlin Heidelberg 2010. Chapter 15, pp. 249-270. 15.2.4.1. Haematophagy : pp. 255f. doi : 10.1007 / 978-3-642-12340-5_15
- John W. Tunnell, Jean Andrews, Noe C Barrera, Fabio Moretzsohn: Encyclopedia of Texas Seashells: Identification, Ecology, Distribution, and History . Texas A&M University Press, College Station (Texas) 2010. 512 pp. Cancellariidae : p. 234.
- Philippe Bouchet & Jean-Pierre Rocroi: Part 2. Working classification of the Gastropoda . Malacologia, 47: 239-283, Ann Arbor 2005 ISSN 0076-2997
- Winston Ponder & David Lindberg, Towards a phylogeny of gastropod molluscs; an analysis using morphological characters . Zoological Journal of the Linnean Society, 119: 83-265, London 1997 ISSN 0024-4082
- Frank Riedel: Origin and evolution of the "higher" Caenogastropoda . Berliner Geoscientific Abhandlungen, Series E, Volume 32, Berlin 2000, 240 pages, ISBN 3-89582-077-6 .
