With over 1700 recognized recent and fossil species,[2] this is among the most diverse families of terrestrial 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".
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.
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.
In this family, the number of haploidchromosomes lies between 21 and 30 (according to the values in this table).[3]
Cochlodina A. Férussac, 1821 - with four subgenera: Cochlodina; Cochlodinastra H. Nordsieck, 1977; Paracochlodina H. Nordsieck, 1969; Procochlodina H. Nordsieck, 1969
Bathyptychia Lindholm, 1925 - with three subgenera: Bathyptychia; Brachyptychia H. Nordsieck, 2001 and Strictiphaedusa H. Nordsieck, 2001
Castanophaedusa Páll-Gergely & Szekeres, 2017
Celsiphaedusa H. Nordsieck, 2001
Changphaedusa Motochin & Ueshima, 2017
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
Euphaedusa O. Boettger, 1877 - with subgenera: Dentiphaedusa H. Nordsieck, 2003; Euphaedusa; and Telophaedusa H. Nordsieck, 2003
Fuchsiana Gredler, 1887
Hemiphaedusa O. Boettger, 1877 - with subgenera: Dendrophaedusa H. Nordsieck, 2002; Hemiphaedusa; Hemiphaedusoides H. Nordsieck, 2001; Hemizaptyx Pilsbry, 1905; Labyrinthiphaedusa H. Nordsieck, 2001;; Pinguiphaedusa Azuma, 1982; Placeophaedusa Minato, 1994)
Juttingia Loosjes, 1965 - with two subgenera: Juttingia and Pseudohemiphaedusa H. Nordsieck, 2002
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).[14]
Oospira Blanford, 1872[15] - with subgenera Formosanella H. Nordsieck, 2003; Oospira; Paraformosella H. Nordsieck, 2003 and Siphonophaedusa Lindholm, 1924
Papilliphaedusa H. Nordsieck, 2003
Paraphaedusa O. Boettger, 1877
Phaedusa H. & A.Adams, 1855 - with subgenera: Metaphaedusa H. Nordsieck, 2001; Phaedusa; Pseudophaedusa Tomiyama, 1984
Probosciphaedusa Z.-Y. Chen, 2021
Reinia Kobelt, 1876 - with three subgenera: Parareinia H. Nordsieck, 1998; Pictophaedusa Azuma, 1982 and Reinia
Serriphaedusa H. Nordsieck, 2001
Sinigena Lindholm, 1925
Solitariphaedusa Motochin & Ueshima, 2017
Stereophaedusa O. Boettger, 1877
Streptodera Lindholm, 1925
Tauphaedusa H. Nordsieck, 2003
Tosaphaedusa Ehrmann, 1929
Zaptyx Pilsbry, 1901 - with two subgenera: Prozaptyx Loosjes, 1950 and Zaptyx
Barker G. M.: Gastropods on Land: Phylogeny, Diversity and Adaptive Morphology. in Barker G. M. (ed.): The biology of terrestrial molluscs. CABI Publishing, Oxon, UK, 2001, ISBN0-85199-318-4. 1-146, cited pages: 139 and 142.
Gittenberger E. & Uit de Weerd D. R. (2009). "Summarizing data on the Inchoatia taxa, including Inchoatia megdova bruggeni subspec. nov. (Gastropoda, Pulmonata, Clausiliidae)" Zoologische Mededelingen83http://www.zoologischemededelingen.nl/83/nr03/a08Archived 16 January 2014 at the Wayback Machine
Nordsieck H. (2007). Worldwide Door Snails. ConchBooks, 213 pp.ISBN978-3-939767-07-7.
Uit de Weerd D. R. (2004). "Molecular phylogenetic history of eastern Mediterranean Alopiinae, a group of morphologically indeterminate land snails". Doctoral thesis, Department of Biology, Faculty of Science, Leiden University. HTM, PDF.
Páll-Gergely B. & Szekeres M. , 2017. New and little-known Clausiliidae (Gastropoda: Pulmonata) from Laos and southern Vietnam. Journal of Conchology 42(6): 507-519
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