Anceya

{{Short description|Genus of gastropods}} {{Automatic taxobox | image = | taxon = Anceya | authority = Bourguignat, 1885<ref>Bourguignat J. R. (1885). ''Notice prodromique sur les mollusques terrestres et fluviatiles recueillis par M. Victor Giraud dans la region méridionale du lac Tanganika''. Paris. [https://archive.org/stream/noticeprodromiqu00bour#page/10/mode/2up page 10].</ref> | diversity_ref = <ref name="Brown 1994"/> | diversity_link = #Species | diversity = 2 species | synonyms_ref = <ref name="Brown 1994">Brown D. S. (1994). ''Freshwater Snails of Africa and their Medical Importance''. Taylor & Francis. {{ISBN|0-7484-0026-5}}.</ref> | synonyms = ''Burtonilla'' E. A. Smith, 1904<ref>Smith E. A. (1904). "Some remarks on the Mollusca of Lake Tanganyika". ''Proceedings of the Malacological Society of London'' '''6''': [https://archive.org/stream/proceedingsofmal164190415mala#page/76/mode/2up 77]-104.</ref> }}

'''''Anceya''''' is a genus of tropical freshwater snails with an operculum, aquatic gastropod mollusks in the subfamily Hauttecoeuriinae of thee family Paludomidae.<ref name="WoRMS">MolluscaBase eds. (2025). MolluscaBase. Anceya Bourguignat, 1885. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=1057378 on 2025-07-30</ref>

==Etymology== The name ''Anceya'' is in honor of César Marie Félix Ancey.

==Distribution== This genus is endemic to Lake Tanganyika.<ref name="Brown 1994">Brown D. S. (1994). ''Freshwater Snails of Africa and their Medical Importance''. Taylor & Francis. {{ISBN|0-7484-0026-5}}.</ref>

==Description== (Original description in French) This new genus is created for a very small, dextral clausiliiform shell possessing a columellar fold and a palatal fold, like ''Clausilia'', but lacking a clausilium, like ''Temesa'', with which it cannot be assimilated. Indeed, in ''Temesa'', the two characteristic parietal folds, which are never absent, are only inferior and do not extend to the upper whorls, whereas in our new genus, the columellar parietal fold spirals up to the apex of the axis, similar to ''Sesteria'' or ''Syrnolopsis''. Furthermore, the shape and ornamentation of ''Anceya'' are so different from those of ''Temesa'' that it would be foolish to classify our new genus within that genus.

To form an idea of Anceya's mode of ornamentation, one only needs to examine ''Clausilia lanzai'' from Dalmatia, and even then, one will only have a weak, very imperfect idea of the Anceyan costulations.

''Anceya'', with the exception of the two upper whorls, is entirely covered by large, lamellar folds, very regular, widely spaced from each other, and directed in a slightly oblique manner from right to left. These folds do not resemble ordinary ribs; instead, being very broad at their base and thinned at their edge (consequently pyramidal), they imitate the pinches that fingers would produce on a malleable material. The body whorl, in addition to these folds, is ornamented towards its lower two-thirds with an elevated, carinating spiral rib, circumscribing the inferior surface. This surface is almost flat and finely striolated, as the large folds abruptly stop at this spiral rib.

To these singular characteristics, one must also add those of the aperture. This presents two canaliform sinuses: one at the base of the columella, the other superiorly at the insertion of the outer lip. This insertion is relatively very distant from the convexity of the penultimate whorl.

This genus to which I attribute the name of one of our friends, C. F. Ancey, one of the founding members of the Société malacologique de France, is thus one of the most singular, and despite its singularity, I believe it must take its place in the classification, alongside the genera Temesa, Balia, Abbadia, etc.<ref>{{cite book |last1=Bourguignat |first1=J.R. |title=Notice prodromique sur les mollusques terrestres et fluviatiles recueillis par M. Victor Giraud dans la région méridionale du lac Tanganyika |date=1885 |publisher=Mme Ve TREMBLAY |location=Paris |page=14 |url=https://www.biodiversitylibrary.org/page/12908671 |access-date=30 July 2025}}</ref>

==Species== This genus includes the following two species: * ''Anceya giraudi'' Bourguignat, 1885<ref>{{cite iucn |author=Ngereza, C. |date=2010 |title=''Anceya giraudi'' |volume=2010 |article-number=e.T1256A3358458 |doi=10.2305/IUCN.UK.2010-3.RLTS.T1256A3358458.en |access-date=14 November 2021}}</ref> - type species<ref name="Brown 1994"/> * ''Anceya terebriformis'' (Smith, 1890)<ref>{{cite iucn |author=Ngereza, C. |date=2010 |title=''Anceya terebriformis'' |volume=2010 |article-number=e.T1257A3360644 |doi=10.2305/IUCN.UK.2010-3.RLTS.T1257A3360644.en |access-date=14 November 2021}}</ref><ref name="Brown 1994"/>

;Synonyms: * ''Anceya admirabilis'' Bourguignat, 1890: synonym of ''Anceya giraudi'' Bourguignat, 1885 (junior synonym) * ''Anceya bella'' Pilsbry & Bequaert, 1927: synonym of ''Anceya giraudi'' Bourguignat, 1885 (junior synonym) * ''Anceya rufocincta'' E. A. Smith, 1906: synonym of ''Anceya giraudi'' Bourguignat, 1885 (junior synonym)

==References== {{Reflist}}

== Further reading == * {{cite journal |last1=Pilsbry, H. A. & Bequaert, J. C. |title=The aquatic mollusks of the Belgian Congo: with a geographical and ecological account of Congo malacology. |journal=Bulletin of the American Museum of Natural History |date=1927 |volume=53 |page=235 |url=http://hdl.handle.net/2246/975}} * Mandahl-Barth G. (1954). "The anatomy and systematic position of the Tanganyikan snails ''Syrnolopsis'' and ''Anceya''". ''Annales du Musée Royal du Congo Belge'', 4°, Sciences Zoologiques '''1''': 217–221.

Category:Paludomidae Category:Taxonomy articles created by Polbot Category:Taxa named by Jules René Bourguignat