Streptocyclammina

Streptocyclammina
Temporal range: Jurassic
Scientific classification
Domain: Eukaryota
Phylum: Retaria
Subphylum: Foraminifera
Class: Rotaliata
Order: Textulariida
Family: Spirocyclinidae
Genus: Streptocyclammina
Hottinger, 1967

Streptocyclammina is a benthic foram with a flattened test from the Jurassic. The test (or shell) usually starts off streptospiral (coiled irregularly) hence the name, and becomes planispiral in the mature stage. Chambers are numerous per whorl, whorls become rappidy larger in peneropline fashion (as common in Pereroplis). Sutures between whorls are slightly indented, the periphery rounded. The wall is finely agglutinated, externally imperorate, internally with massive septa perforated by numerous apertures.

Streptocyclammina has been found in Jurassic sediments in Morocco, Italy, and the Balkans. Spiraloconulus and Timidonella are other spirocyclinids from the same general region, but are limited to the middle Jurassic.

References

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