Extra extra
Species of gastropod
title: "Extra extra" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["cystiscidae", "gastropods-described-in-1894"] description: "Species of gastropod" topic_path: "general/cystiscidae" source: "https://en.wikipedia.org/wiki/Extra_extra" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0
::summary Species of gastropod ::
::callout[type=note] the mollusc ::
| image = Extra extra (MNHN-IM-2000-557).jpeg | image_caption = | display_parents = 3 | genus = Extra | species = extra | authority = (Jousseaume, 1894) | synonyms_ref = | synonyms = *Marginella extra Jousseaume, 1894
Extra extra or Marginella extra is a species of small sea snail, a marine gastropod mollusk or micromollusk in the family Cystiscidae. Some malacologists place this genus more simply in the family Marginellidae.
Taxonomy
Marginella extra was originally described under name Extra extra by French zoologist Félix Pierre Jousseaume in 1894. He placed this species to the monotypic genus Extra Jousseaume, 1894. Dautzenberg (1929) moved this species into genus Marginella.
Diagnosis
The shell is minute, white, semitranslucent; prominent axial costae present; spire sunken but not immersed; lip strongly thickened, smooth, lacking denticulation, flared posteriorly; siphonal notch absent; posterior notch absent; distinct parietal callus "shield" present; columella multiplicate, with 5 plications plus parietal lirae, plications slightly excavated inside aperture due to parietal callus deposits.
Distribution and habitat
Recorded only from western Indian Ocean along Madagascar, apparently in shallow water.
References
References
- (1894). "Diagnoses des coquilles de nouveaux mollusques". Bulletin de la Société Philomathique de Paris.
- WoRMS (2009). ''Extra extra'' (Jousseaume, 1894). Accessed through the World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=217193 on 4 December 2010
- Dautzenberg, Ph. (1929). Mollusques testaces marins de Madagascar. Faune des Colonies Françaises, Tome III
::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::