Extra extra
| Extra extra | |
|---|---|
 | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| (unranked): | clade Caenogastropoda clade Hypsogastropoda clade Neogastropoda |
| Superfamily: | Muricoidea |
| Family: | Cystiscidae / Marginellidae |
| Subfamily: | Cystiscinae |
| Genus: | Extra / Marginella Jousseaume, 1894 |
| Species: | E. extra / M. extra |
| Binomial name | |
| Extra extra (Jousseaume, 1894) | |
| Synonyms | |
|
Marginella extra Jousseaume, 1894 | |
Extra extra or Marginella extra[1] is a species of minute 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)[2] 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; collumela 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
- ↑ 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
- Coovert G. A. & Coovert H. K. (1995). "Revision of the Supraspecific Classification of Marginelliform Gastropods". The Nautilus 109(2 & 3):43-110.