Spiraloconulus

Spiraloconulus
Temporal range: Middle Jurassic
Scientific classification
Kingdom: Chromista
Subkingdom: Rhizaria
Phylum: Foraminifera
Class: Rotaliata
Order: Textulariida
Family: Spirocyclinidae
Genus: Spiraloconulus
Allemann and Schroeder, 1980

Spiraloconulus is a middle Jurassic foram species with a coarsly agglutinated, microgranular, calcareous wall. The test is large, conical to cylindrical, coiled to straight(ish); the early coiled stage results in a flattened apex. Distinctly coiled microspheric tests are as much as 2 mm wide and 1.6 mm high. Megalospheric tests are smaller, up to 1.5 mm high and 1.1 mm wide.

Spiraloconulus is known from the middle Jurassic of France, Italy, Sardinia, and Arabia. Timidonella is another spirocyclind from the same time, but with a wider distribution.

References

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