''Ringicella'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of tropical 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 gastropod mollusks that have shells (those without shells are known as ...

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 ...

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 includ ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

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

Odontostomidae Odontostomidae is a taxonomic family of medium-sized to large, air-breathing, tropical and sub-tropical land snails, terrestrial pulmonate gastropod molluscs in the superfamily Orthalicoidea.Breure A. S. H. & Romero P. (2012). "Support and su ...

. Adult snails of this genus have an extremely unusual

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 ou ...

morphology, very similar to that found in the genus '' Anostoma''

Fischer von Waldheim Gotthelf Fischer von Waldheim (russian: Григо́рий Ива́нович Фи́шер фон Ва́льдгейм, translit=Grigórij Ivánovič Fíšer fon Vál'dgejm; 13 October 1771 – 18 October 1853) was a Saxon anatomist, entomol ...

, 1807, of which this genus was previously considered to be merely a

subgenus In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

. The adult snails in this genus carry their shells upside down, with the

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. Spires are ...

apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics), a teenaged super villainess in the Marvel Universe * Ape-X, a super-intelligent ape in the Squadron Supreme universe *Apex ...

at the bottom, and the umbilicus at the top.

Shell description

The shell of ''Ringicella'' is very similar to that of '' Anostoma''. Shells of the genus ''Ringicella'' have an additional feature: the angular lamella and upper suprapalatal fold are concrescent, forming a perforation in the lip at its upper end. In addition, the apertural rim incorporates a small tube, which communicates with the interior of the shell. The width of adult shells varies from 18 to 25 mm.

Anatomy

This section is based on the anatomy of ''Ringicella ringens'', which is also valid for the genus '' Anostoma'' (according to 1901 information from Pilsbry). Unlike the shell, the soft anatomy is not especially peculiar, in so far as it is known from Dr. Paul Fischer's (1857) account of ''Ringicella ringens''.

Radula

The jaw and teeth are as they are in '' Macrodontes''. The

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

of ''Ringicella'' (and also ''Macrodontes'') is rather aberrant for Bulimulinae: the central and lateral teeth have no side cusps, the marginals have an ectocone; the basal plate is short. Pilsbry H. A. 1901. in Tryon G. W. & Pilsbry H. A. 1901-1902
''Oriental Bulimoid Helicidae. Odontostominae. Cerionidae'' Volume 14
Manual of Conchology. Second series: Pulmonata. pag
25
��28 and 109–114. The article incorporates public domain texts from this reference. The jaw is smooth, arcuate. The teeth are as in the terrestrial Holopoda (se
taxonomy of Holopoda
generally, the centrals and laterals with single broad cusps, marginals short, with the ectocone developed.

Genitalia

The genitalia are essentially similar to those of ''

Odontostomus ''Odontostomus'' is a genus of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Odontostomidae.Breure A. S. H. & Ablett J. D. (2012) "Annotated type catalogue of the Bothriembryontidae and Odontostomidae (Mollusc ...

''. The genitalia are exceedingly lengthened in ''Ringicella''. The genitalia are of the haplogonous type, the long slender penis passing into a long vas deferens, upon which the penis retractor muscle is inserted; the duct of the globular spermatheca is extremely long. The elongation of the whole genital system is greater than in Helicoid snails generally, and doubtless correlated with the unusual length of the last whorl. Araujo (1963) described male copulatory organs of ''Ringicella ringens'' as spirally coiled, that is different from previous description by Fischer and by Pilsbry.

Central nervous system

The cerebral

ganglia A ganglion is a group of neuron cell bodies in the peripheral nervous system. In the somatic nervous system this includes dorsal root ganglia and trigeminal ganglia among a few others. In the autonomic nervous system there are both sympatheti ...

are more separated than usual in the Holopoda. The cerebral ganglia are connected by a short narrow

commissure A commissure () is the location at which two objects abut or are joined. The term is used especially in the fields of anatomy and biology. * The most common usage of the term refers to the brain's commissures, of which there are five. Such a commi ...

; the suboesophageal ganglia are as usual in the Bulimulinae.

Distribution

This genus of snails occurs in

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

. Pilsbry (1901) mentioned '' Ringicella carinatum'' as also occurring in

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...

, in

high forest A high forest is a type of forest originated from seed or from planted seedlings. In contrast to a low forest (also known as a coppice forest), a high forest usually consists of large, tall mature trees with a closed canopy. High forests can occu ...

s of the

Magdalena river The Magdalena River ( es, Río Magdalena, ; less commonly ) is the main river of Colombia, flowing northward about through the western half of the country. It takes its name from the biblical figure Mary Magdalene. It is navigable through much of ...

basin at 1830 m (6000 feet) above sea level, but Vera Ardila (2008) considers the presence of the species in Colombia to be doubtful.

Species

Species within this genus include: * '' Ringicella carinatum'' (Pfeiffer, 1853) - synonym: ''Anostoma carinatum'' Pfeiffer, 1853 * '' Ringicella luetzelburgi'' (Weber, 1925) - synonym: ''Anostoma luetzelburgi'' (Weber, 1925) * '' Ringicella ringens'' (Linnaeus, 1758) - synonyms: ''Anostoma ringens'' (Linnaeus, 1758), ''Anostoma globulosa'' Lamarck, 1822,Lamarck, J.B.P.A. 1819-1822. ''Mollusques In Histoire Naturelle des Animaux sans vertebres''. Paris. 6 (1): 1-343 (1819), (2): 1-232 (1822). page 101. ''Anostoma globulosum'' Lamarck, 18221866
''Catalogue of the genera Helix, Anostoma, Hypselostoma, Streptaxis, Tomigerus, Bulimus, Orthalicus, Partula, in the collection of A.D. Brown, Princeton, New Jersey''
/ref>

References

The article incorporates public domain texts from the reference {{Taxonbar, from=Q7334890 Odontostomidae Taxa named by John Edward Gray