Rhytididae

Rhytididae
A live Powelliphanta augusta from the upper Waimangaroa River.
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Superorder:	Eupulmonata
Order:	Stylommatophora
Superfamily:	Rhytidoidea
Family:	Rhytididae Pilsbry, 1893

Rhytididae is a taxonomic family of medium-sized predatory air-breathing land snails, carnivorous terrestrial pulmonate gastropod molluscs in the superfamily Rhytidoidea.

This family has two subfamilies:

• Chlamydephorinae Cockerell, 1935 (1903)
• Rhytidinae Pilsbry, 1893

A shell of Powelliphanta hochstetteri hochstetteri.

Anatomy

In this family, the number of haploid chromosomes lies between 26 and 35 (according to the values in this table).

Distribution

This family of land snails has a range which extends from South Africa to New Guinea, some of the higher South Pacific islands, New Zealand and Australia.

The New Zealand genera include Delos, Delouagapia, Paryphanta, Powelliphanta, Rhytida, Wainuia and Schizoglossa. These, however, probably do not form a monophyletic group, as indicated by their differences in their size, shape and radular morphology.

Genera

Radulae of three species representing three Rhytidae genera. (A) Natalina beyrichi, scale bar = 1.0 mm; (B) Afrorhytida kraussi, scale bar = 500 μm; (C) Capitina calcicola sp., scale bar = 250 μm.

Genera within the family Rhytididae include:

• Afrorhytida
• Amborhytida
• Austrorhytida
• Capitina
• Delos
• Delouagapia
• Diplomphalus
• Echotrida
• Hebridelos
• Macrocycloides
• Namoitena
• Nata
• Natalina
• Occirhenea
• Ougapia
• Paryphanta
• Protorugosa
• Powelliphanta
• Prolesophanta
• Pseudomphalus Ancey, 1882
• Ptychorhytida
• Rhytida
• Rhytidarex
• Saladelos
• Schizoglossa
• Strangesta
• Tasmaphena
• Torresiropa
• Victaphanta
• Vitellidelos
• Wainuia

Life cycle

Eggs of New Zealand's species are generally deposited in leaf mould. Eggs are usually laid from late October to early December, with exception in some species as Powelliphanta spedeni in March.

Further reading

• Trewick, SA; et al. (2008). "Taxonomic and conservation status of a newly discovered giant landsnail from Mount Augustus, New Zealand". Conservation Genetics. 9 (6): 1563–1575. doi:10.1007/s10592-007-9495-8.
• Walker, KJ; et al. (2008). "A new species of Powelliphanta (Mollusca: Pulmonata: Rhytididae) land snail from the Stockton Plateau, New Zealand". Journal of the Royal Society of New Zealand. 38 (3): 163–186. doi:10.1080/03014220809510553.
• Powell, A. W. B. (1930). "The Paryphantidae of New Zealand: their Hypothetical Ancestry, with descriptions of New Species and a New Genus". Records of the Auckland Institute and Museum. 1: 17–56. ISSN 0067-0464. JSTOR 42905933. Wikidata Q58676532.
• Powell, A. W. B. (1938). "The Paryphantidae of New Zealand No. IV. and The Genus Placostylus in New Zealand". Records of the Auckland Institute and Museum. 2: 133–150. ISSN 0067-0464. JSTOR 42905975. Wikidata Q58676598.
• Powell, A. W. B. (1946). "The Paryphantidae of New Zealand. No. V. Further New Species of Paryphanta, Wainuia and Rhytida". Records of the Auckland Institute and Museum. 3: 99–136. ISSN 0067-0464. JSTOR 42905998. Wikidata Q58676634.
• Smith B. J. 1998. Family Rhytididae. In: Beesley P. L., Ross G. J. B. & Wells A. ed. Mollusca: the southern synthesis. Fauna of Australia. Vol. 5. Melbourne, CSIRO Publishing. Pp. 1091–1093.
• Spencer H. G., Brook F. J. & Kenned M. (March 2006) "Phylogeography of Kauri Snails and their allies from Northland, New Zealand (Mollusca: Gastropoda: Rhytididae: Paryphantinae)". Molecular Phylogenetics and Evolution 38(3): 835–842. doi:10.1016/j.ympev.2005.10.015
• Te Punga M. T. (1953) "The Paryphantidae and a Cook Strait land bridge". New Zealand Journal of Science and Technology 35: 51–63.