Allenoconcha retinaculum

{{Short description|Species of gastropod}} {{Use dmy dates|date=February 2021}} {{Speciesbox | image = | status = VU | status_system = IUCN2.3 | status_ref = <ref>{{cite iucn |author=Ponder, W.F. |author2=Varman, R. |date=1996 |title=''Buffetia retinaculum'' |volume=1996 |article-number=e.T3166A9644211 |doi=10.2305/IUCN.UK.1996.RLTS.T3166A9644211.en |access-date=17 November 2021}}</ref> | genus = Allenoconcha | species = retinaculum | authority = (Preston, 1913) | synonyms = * ''Buffetia retinaculum'' <small>(Preston, 1913)</small> (unavailable genus name) * ''Nitor retinaculum'' <small>Preston, 1913</small> (original combination) }}

'''''Allenoconcha retinaculum''''' is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Microcystidae.<ref name="WoRMS">MolluscaBase eds. (2021). MolluscaBase. Allenoconcha retinaculum (Preston, 1913). Accessed through: World Register of Marine Species at: http://marinespecies.org/aphia.php?p=taxdetails&id=1421761 on 2021-02-28</ref>

==Description== The height of the shell attains 1.5 mm, its diameter 3 mm.

(Original description) The small shell is conically depressed. It is thin, transparent, and slightly glossy with a yellowish-brown hue. It consists of four whorls that increase in size regularly, with the body whorl being subtly angled at the periphery. The shell is sculpted with closely spaced, oblique, arcuate folds, which are more pronounced on the later whorls. The suture is distinctly impressed. The columella margin is curved at the top, descending very obliquely, and thickened inwardly into a whitish, loop-like lamella, visible through the shell. The outer lip is sharp, and the aperture is obliquely compressed and slightly elevated.<ref>[https://www.biodiversitylibrary.org/page/22100009 Preston, H. B. (1913). Characters of new genera and species of terrestrial Mollusca from Norfolk Island. The Annals and magazine of natural history; including zoology, botany, and geology. Eighth series. 12 (72): 522-538. London] {{source-attribution}} </ref>

==Distribution== This species is endemic to Norfolk Island.

==References== {{Reflist}}

==External links== * [https://doi.org/10.1080/13235818.2020.1724603 Köhler, F.; Bouchet, P. (2020). On unavailable genus-group names introduced by Tom Iredale for Australian non-marine gastropods: nomenclatural clarifications and descriptions of new genera. Molluscan Research. 40(2): 150–159]

Category:Allenoconcha Category:Gastropods of Norfolk Island Category:Vulnerable fauna of Australia Category:Gastropods described in 1913 Category:Taxonomy articles created by Polbot Category:Taxobox binomials not recognized by IUCN Category:Taxa named by Hugh Berthon Preston