Clausiliidae, also known by their common name the door snails, are a taxonomic family of small, very elongate, mostly left-handed, air-breathing land snails, sinistral terrestrial pulmonate gastropod mollusks.
With about 1,300 species recent and fossil, this belong among the most diverse families of land gastropods (cf. Orthalicidae, although the marine gastropod family Pyramidellidae is larger).
Most species of Clausiliidae have an anatomical structure known as a clausilium, which enables the snail to close off the aperture of the shell with a sliding "door".
Shell description
Almost all the species of snails in the family of door snails are left-handed, which is an uncommon feature in gastropod shells in general.
These snails have shells which are extremely high-spired, with numerous whorls.
The shells tend to be club-shaped, tapering at both ends to a rounded nub. The aperture usually has visible folds.
The clausilium
Clausiliids are also very unusual among pulmonate gastropods in that most of them have a "door" or clausilium. The clausilium is not the same thing as an operculum, which does not exist at all in pulmonate gastropods.
The clausilium is a calcareous structure, tongue-shaped or spoon-shaped, which can close the aperture of the snail shell to protect the soft parts against predation by animals such as carnivorous beetle larvae. The narrow end of the clausilium slides in the grooves that are formed by the folds on the inside of the shell.
Anatomy
In this family, the number of haploid chromosomes lies between 21 and 30 (according to the values in this table).
The Clausiliidae family is classified within the informal group Sigmurethra, itself belonging to the cladeStylommatophora within the clade Eupulmonata (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).
2005 taxonomy
The taxonomy of the Gastropoda by Bouchet & Rocroi, 2005 recognizes subfamilies as follows:
Alopia H. & A.Adams, 1855 - with two subgenera Alopia and Kimakowiczia Szekeres, 1969
Herilla H. & A. Adams, 1855
Triloba Vest, 1867
tribe Cochlodinini
Cochlodina A. Férussac, 1821 - with four subgenera: Cochlodina; Cochlodinastra H. Nordsieck, 1977; Paracochlodina H. Nordsieck, 1969; Procochlodina H. Nordsieck, 1969
Macedonica O. Boettger, 1877
tribe Delimini
Barcania Brandt, 1956
Charpentieria Stabille, 1864 - with four subgenera: Charpentieria; Gibbularia Monterosato, 1908; Mauritanica O. Boettger, 1877; Siciliaria Vest, 1867 and Stigmatica O. Boettger, 1877
Delima Hartmann, 1842 - with four subgenera: Delima; Dugiana Stamol & Slapnik, 2002; Piceata O. Boettger, 1877 and Semirugata O. Boettger, 1877
Agathylla H. & A.Adams, 1855 - with two subgenera Agathylla and Agathyllina H. Nordsieck, 1969
Albinaria Vest, 1867 - also include former genera Carinigera Moellendorff, 1873; Cristataria Vest, 1867; Isabellaria Vest, 1867; Sericata O. Boettger, 1878.
Phaedusa H. & A.Adams, 1855 - with four subgenera: Metaphaedusa H. Nordsieck, 2001; Phaedusa; Pseudophaedusa Tomiyama, 1984 and Stereophaedusa O. Boettger, 1877
tribe Megalophaedusini
Leptacme Ehrmann, 1927
Oospira Blanford, 1872 - with five subgenera: Atractophaedusa Ehrmann, 1927; Formosana O. Boettger, 1877; Formosanella H. Nordsieck, 2003; Oospira; Paraformosella H. Nordsieck, 2003 and Siphonophaedusa Lindholm, 1924
Zaptyx Pilsbry, 1901 - with two subgenera: Prozaptyx Loosjes, 1950 and Zaptyx
tribe ?
Acanthophaedusa H. Nordsieck, 2007
Bathyptychia Lindholm, 1925 - with three subgenera: Bathyptychia; Brachyptychia H. Nordsieck, 2001 and Strictiphaedusa H. Nordsieck, 2001
Celsiphaedusa H. Nordsieck, 2001
Cylindrophaedusa O. Boettger, 1877 - with three subgenera: Cylindrophaedusa and Montiphaedusa H. Nordsieck, 2002
Dautzenbergiella Lindholm, 1924 - with two subgenera: Dautzenbergiella and Mansuyiella H. Nordsieck, 2003
Diceratoptyx Pilsbry, 1905
Euphaedusa O. Boettger, 1877 - with five subgenera: Dentiphaedusa H. Nordsieck, 2003; Euphaedusa; Papilliphaedusa H. Nordsieck, 2003; Tauphaedusa H. Nordsieck, 2003 and Telophaedusa H. Nordsieck, 2003
Fuchsiana Gredler, 1887
Hemiphaedusa O. Boettger, 1877 - with 10 subgenera: Dendrophaedusa H. Nordsieck, 2002; Hemiphaedusa; Hemiphaedusoides H. Nordsieck, 2001; Hemizaptyx Pilsbry, 1905; Labyrinthiphaedusa H. Nordsieck, 2001; Margaritiphaedusa H. Nordsieck, 2001; Notoptychia Ehrmann, 1927; Pinguiphaedusa Azuma, 1982; Placeophaedusa Minato, 1994 and Selenophaedusa Lindholm, 1924
Heterozaptyx Pilsbry, 1906
Juttingia Loosjes, 1965 - with two subgenera: Juttingia and Pseudohemiphaedusa H. Nordsieck, 2002
Lindholmiella Ehrmann, 1927
Liparophaedusa Lindholm, 1924
Loosjesia H. Nordsieck, 2002
Luchuphaedusa Pilsbry, 1901 - with two subgenera: Luchuphaedusa and Nesiophaedusa Pilsbry, 1905
Macrophaedusa Moellendorff, 1883
Macrophaedusella H. Nordsieck, 2001
Megalophaedusa O. Boettger, 1877 - with four subgenera: Megalophaedusa; Mesophaedusa Ehrmann, 1929; Mesozaptyx Kuroda, 1963 and Mundiphaedusa Minato, 1979. (Neophaedusa is a synonym of Megalophaedusa).
Metazaptyx Pilsbry, 1905
Miraphaedusa H. Nordsieck, 2005
Oligozaptx Pilsbry, 1905
Paraphedusa O. Boettger, 1877
Parazaptyx Pilsbry, 1905
Pliciphaedusa H. Nordsieck, 1998
Pulchraptyx Minato, 1981
Reinia Kobelt, 1876 - with three subgenera: Parareinia H. Nordsieck, 1998; Pictophaedusa Azuma, 1982 and Reinia
