Ammonoid
Cleoniceras
Madagascar ammonite
Cleoniceras is the Albian ammonite of the Mahajanga Basin, Madagascar, sold by the ton cut and polished into halves that show the chambers filled with calcite, or whole with iridescent shell. It is the most common ammonite on the market and fully legal to export from Madagascar with paperwork. Polished halves are genuine but the natural shell on 'whole' specimens is often stabilised or painted; fake sutures carved into steinkerns also occur.
| Phylum | Mollusca |
|---|---|
| Class | Cephalopoda |
| Order | Ammonitida |
| Family | Cleoniceratidae |
| Group | Ammonoid |
| Rank (PBDB) | genus· Paleobiology Database |
| Author | Parona and Bonarelli 1897· Paleobiology Database |
| Classification (PBDB) | Mollusca › Cephalopoda › Ammonitida › Cleoniceratidae· Paleobiology Database |
| Range (PBDB) | 113–100 Ma· Paleobiology Database |
| PBDB occurrences | 45· Paleobiology Database |
Elsewhere
- GBIF: 4627259
- PBDB: 14696
- Wikidata: Q5131706
- PBDB taxon page
- Wikipedia: Cleoniceras
- PBDB search: Cleoniceras
Cite this article
Stratum Study. "Cleoniceras" (Taxon). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/taxa/cleoniceras. Accessed 2026-09-20.
@misc{stratum-cleoniceras,
title = {Cleoniceras},
author = {{Stratum Study}},
howpublished = {\url{https://stratum.black/study/taxa/cleoniceras}},
year = {2026},
note = {Taxon article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, pbdb, wikidata, commons. Accessed 2026-09-20.}
} Citations carry the pack version and the article's as-of date so they resolve to the same text later. The facts themselves belong to the sources listed below; cite those for the science.