Anostoma

Anostoma
A colored drawing of an adult shell of Anostoma octodentatum
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Order: Stylommatophora
Suborder: Helicina
Superfamily: Orthalicoidea
Family: Odontostomidae
Genus: Anostoma
Fischer von Waldheim, 1807[1]
Synonyms

Also note that this genus name has frequently been misspelled as "Anastoma"

  • Angystoma Schumacher, 1817
  • Anostoma (Anostoma) Fischer von Waldheim, 1807· accepted, alternate representation
  • Anostoma (Ringicella) Gray, 1847· accepted, alternate representation
  • Tomogeres Montfort, 1810
  • Tomogerina Jousseaume, 1877

Anostoma, common name the up-mouth snails, is a genus of tropical air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Odontostomidae.[2] Snails in this genus are found in Brazil.

Adult snails in this genus have an extremely unusual shell morphology: the aperture of the adult shell faces directly "upwards", in other words, in the same direction as the spire.[3] This seemingly impossible arrangement is made possible because the adult shell is carried upside down.

In 1901, the American malacologist Henry Augustus Pilsbry[3] commented that the adult shell of Anostoma is "so bizarre that in the total absence of information upon its life history, no useful theory can be formulated to account for its peculiarities."

A very similar shell is found in the genus Ringicella Gray, 1847, which was previously considered to be merely a subgenus within Anostoma, but it is now considered to be a genus in its own right.

  1. ^ Fischer von Waldheim, G. 1807. Vegetaux et Animaux 3: IX+330, 6 pls. In Conchyliologie. Muséum Demidoff, ou catalogue systématique et raisonné des curiosités de la nature et de l’art données à Université Impériale de Moscou par S. E. M. Paul de Demidoff.
  2. ^ Breure A. S. H. & Ablett J. D. (2012) "Annotated type catalogue of the Bothriembryontidae and Odontostomidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London". ZooKeys 182: 1-70. doi:10.3897/zookeys.182.2720.
  3. ^ a b Cite error: The named reference Pilsbry was invoked but never defined (see the help page).