Zonitidae,

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...

the true glass snails, are a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

of mostly rather small, air-breathing

land snail A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial molluscs, terrestrial gastropod mollusks that have gastropod shell, shel ...

s, terrestrial

pulmonate Pulmonata or pulmonates is an informal group (previously an order, and before that, a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group inclu ...

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

s in the superfamily Zonitoidea. Zonitidae is the only family in the superfamily Zonitoidea. The family's

type genus In biological taxonomy, the type genus (''genus typica'') 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-bearin ...

is '' Zonites'', established by

Pierre Denys de Montfort Pierre Denys de Montfort, also spelt Pierre Dénys de Montfort, (1766–1820) was a French Natural history, naturalist, in particular a malacologist, remembered today for his pioneering inquiries into the existence of the gigantic octopuses. He ...

in 1810. This family has no subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).

Distribution

The distribution of the Zonitidae encompasses the western

Palearctic The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa. Th ...

Shell description

The spiral, heliciform shells of these snails are flattened in shape with a very low

spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spire ...

. The shell is perforate or umbilicate. The lip of the

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

is simple, lacking thickened margin. These shells are more or less transparent as if made of glass, hence the popular name "glass snails". The shells are colorless or of an amber to brownish color.

Biology

Some snails in genera within this family create and use

love dart A love dart (also known as a gypsobelum, shooting darts, or just as darts) is a sharp, calcium carbonate, calcareous or chitinous Dart (missile), dart which some hermaphroditic land snails and slugs create. Love darts are both formed and stor ...

s as part of their mating behavior. In this family, the number of

haploid Ploidy () is the number of complete sets of chromosomes in a cell (biology), cell, and hence the number of possible alleles for Autosome, autosomal and Pseudoautosomal region, pseudoautosomal genes. Here ''sets of chromosomes'' refers to the num ...

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

s lies between 21 and 25 and also lies between 31 and 35, but other values are also possible (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.

Ecology

These snails live in damp places under stones and similar objects. The true glass snails are usually

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

Genera

Genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

within the family Zonitidae include: * '' Aegopis'' Fitzinger, 1833 * '' Aegopinella'' Lindholm, 1927 * '' Allaegopis'' Riedel, 1979 * '' Balcanodiscus'' Riedel & Urbanski, 1964 * '' Brazieria'' Ancey, 1887 * '' Doraegopis'' Riedel, 1982 * '' Eopolita'' Pollonera, 1916 *'' Glyphyalinia'' Martens, 1892 * '' Gollumia'' Riedel, 1988 * † '' Macrozonites'' Wenz, 1919 * '' Meledella'' Sturany, 1908 * '' Mesomphix'' Rafinesque, 1819 * '' Ogaridiscus'' Dall, 1877Turgeon, D.D., J.F. Quinn, Jr., A.E. Bogan, E.V. Coan, F.G. Hochberg, W.G. Lyons, P.M. Mikkelsen, R.J. Neves, C.F.E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F.G. Thompson, M. Vecchione, and J.D. Williams. 1998. ''Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks''. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland: 526 pp. * '' Paraegopis'' Hesse, 1910 * '' Paravitrea'' Pilsbry, 1898 * '' Retinella'' Fischer, 1877 * '' Thasiogenes'' Riedel, 1998 * '' Troglaegopis'' Riedel & Radja, 1983 * '' Turcozonites'' Riedel, 1987 *'' Ventridens'' Binney & Bland, 1869 * '' Zonites'' Montfort, 1810 – type genus

Cladogram

The following

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

shows the phylogenic relationships of this family to other families in the

limacoid clade The Limacoidei is a taxonomic infraorder of air-breathing land snails, semislugs and slugs, terrestrial pulmonate gastropod molluscs in the suborder Helicina. Distribution The original ancestral area of limacoid families is thought to be ...

:Hausdorf B. (2000). "Biogeography of the Limacoidea sensu lato (Gastropoda: Stylommatophora): Vicariance Events and Long-Distance Dispersal". '' Journal of Biogeography'' 27(2): 379–390.
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