''Testacella'' is

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of small to medium-large,

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

y, air-breathing, land slugs. MolluscaBase eds. (2022). MolluscaBase. Testacella Lamarck, 1801. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=818595 on 2022-09-13 They are

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

gastropod

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

s in the family Testacellidae, the shelled slugs. They are not often seen because they live underground. ''Testacella'' is the only genus in the family, in other words it is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

family. ''Testacella'' is the

type genus In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearing type of a nominal ...

of the family Testacellidae.

Distribution

Species within this genus of slugs live in north Africa, southern and western

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

, and Britain."Family summary for Testacellidae"
AnimalBase, last modified 8 August 2010, accessed 28 June 2011.

Species

Species within the genus ''Testacella'' include: * Subgenus ''Testacella'' Draparnaud, 1801 * Subgenus ''Testacelloides'' A. J. Wagner, 1914"''Testacelloides'' A.J. Wagner, 1914"

Fauna Europaea Fauna Europaea is a database of the scientific names and distribution of all living multicellular Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight o ...

, last update 27 January 2011, accessed 28 June 2011. * † '' Testacella asinium'' Serres, 1827 * '' Testacella bisulcata'' Risso, 1826"Species in genus ''Testacella''"
(n=6).

AnimalBase AnimalBase is a project brought to life in 2004 and is maintained by the University of Göttingen, Germany. The goal of the AnimalBase project is to digitize early zoological literature, provide copyright-free open access to zoological works, and pr ...

, accessed 19 January 2011. * '' Testacella bracciai'' Nardi & Bodon, 2011 * † '' Testacella bruntoniana'' Serres, 1851 * † '' Testacella deshayesii'' Michaud, 1855 * '' Testacella fischeriana'' Bourguignat, 1862 * '' Testacella gestroi'' Issel, 1873 * '' Testacella haliotidea'' Lamarck, 1801 - the shelled slug, the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

of the genus * † '' Testacella lartetii'' Dupuy, 1850 * '' Testacella maugei'' Férussac, 1819 * † '' Testacella pedemontana'' Sacco, 1886 * † '' Testacella pontileviensis'' de Morgan, 1920 * † '' Testacella puisseguri'' Schlickum, 1967 * '' Testacella riedeli'' Giusti, Manganelli & Schembri, 1995 * † '' Testacella sandbergeri'' Wenz, 1914 * † '' Testacella schuetti'' Schlickum, 1967 * '' Testacella scutulum'' Sowerby I, 1821 * † '' Testacella zellii'' Klein, 1853 ;Nomen dubium: * ''Testacella antillarum'' Grateloup, 1855 ;Synonyms: * ''Testacella anomala'' Torres Minquez, 1924: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella barcinonensis'' Pollonera, 1888: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella catalonica'' Pollonera, 1888: synonym of ''Testacella scutulum'' G. B. Sowerby I, 1821 (original name) * ''Testacella dikrangensis'' Godwin-Austen, 1876: synonym of '' Girasia dikrangensis'' (Godwin-Austen, 1876) (original combination) * ''Testacella dubia'' Pollonera, 1888: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella esserana'' Fagot, 1892: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella europaea'' de Roissy, 1805: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella galliae'' Oken, 1816: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella guadeloupensis'' Lesson, 1838: synonym of ''

Omalonyx unguis ''Omalonyx unguis'' is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Succineidae, the amber snails. Distribution The distribution of ''Omalonyx unguis'' includes: * Argentina *Brazil *Paraguay ...

'' (d'Orbigny, 1836) (junior synonym) * † ''Testacella larteti'' Dupuy, 1850 : synonym of † T''estacella lartetii'' Dupuy, 1850 (incorrect subsequent spelling) * ''Testacella matheronii'' Potiez & Michaud, 1838: synonym of ''

'' (d'Orbigny, 1836) (junior synonym) * ''Testacella subtrigona'' Pollonera, 1888: synonym of ''Testacella haliotidea'' Draparnaud, 1801(original name) * ''Testacella vagans'' F. W. Hutton, 1882: synonym of ''Testacella maugei'' Férussac, 1819

Description

These slugs have a very small, ear-shaped

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses ** Thin-shell structure Science Biology * Seashell, a hard o ...

, which is situated far back on their bodies. In the family Testacellidae, the number of haploid

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...

s lies between 31 and 35 (according to the values in this table).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, . 1-146, cited pages: 139 and 142.

Habitat

These slugs are rarely observed, but they tend to live in gardens and farms where there is rich soil and a lot of

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. T ...

Life habits

These slugs live underground and hunt earthworms. They are usually only seen when they are forced up to the surface because the soil has become completely saturated with rain. Testacella

References

External links

Lamarck, J. B. (1801). Système des animaux sans vertèbres, ou tableau général des classes, des ordres et des genres de ces animaux; Présentant leurs caractères essentiels et leur distribution, d'apres la considération de leurs rapports naturels et de leur organisation, et suivant l'arrangement établi dans les galeries du Muséum d'Histoire Naturelle, parmi leurs dépouilles conservées; Précédé du discours d'ouverture du Cours de Zoologie, donné dans le Muséum National d'Histoire Naturelle l'an 8 de la République. Published by the author and Deterville, Paris: viii + 432 pp

"''Testacella'' Species"

{{Commons category, Testacella