''Ringicella'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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 molluscs, terrestrial gastropod mollusks that have gastropod shell, shel ...

terrestrial Terrestrial refers to things related to land or the planet Earth, as opposed to extraterrestrial. 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 o ...

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 family

Odontostomidae Odontostomidae is a Taxonomy (biology), taxonomic family (biology), family of medium-sized to large, air-breathing, tropical and sub-tropical land snails, Terrestrial animal, terrestrial pulmonate gastropod Mollusca, molluscs in the superfamily O ...

. 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 Science Biology * Seashell, a hard outer layer of a marine ani ...

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

Fischer von Waldheim Gotthelf Fischer von Waldheim (; 13 October 1771 – 18 October 1853) was a Saxon anatomist, entomologist and paleontologist. Fischer was born as Gotthilf Fischer in Waldheim, Saxony, the son of a linen weaver. He studied medicine at Le ...

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

subgenus In biology, a subgenus ( 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 the ge ...

. 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. Spire ...

apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics) A-Bomb Abomination Absorbing Man Abraxas Abyss Abyss is the name of two characters appearing in Ameri ...

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 (; : radulae or radulas) is an anatomical structure used by mollusks 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 enters ...

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 (: ganglia) 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 a ...

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 wikt:abut#Verb, 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 at ...

; the suboesophageal ganglia are as usual in the Bulimulinae.

Distribution

This genus of snails occurs in

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

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

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

, 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 (, ; 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 its lower reaches, ...

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