Lingulodinium polyedra
Lingulodinium polyedra is a species of motile photosynthetic dinoflagellates. L. polyedra are often the cause of red tides in southern California, leading to bioluminescent displays on beaches at night.
Life cycle
As part of its life cycle, this species produces a resting stage, a dinoflagellate cyst called Lingulodinium machaerophorum. This cyst was first described by Deflandre and Cookson in 1955 from the Miocene of Balcombe Bay, Victoria, Australia as: "Shell globular, subsphaerical or ellipsoidal with a rigid membrane, more brittle than deformable, covered with numerous long, stiff, conical, pointed processes resembling the blade of a dagger. Surface of shell granular or punctate." Its stratigraphic range is the Upper Paleocene of eastern USA and Denmark till Recent.Organic-walled dinocyst morphology is shown to be controlled by changes in salinity and temperature in some species, more particularly process length variation. This morphological variation is known for Lingulodinium machaerophorum from culture experiments, and study of surface sediments.
The morphological variation of process lengths can be applied for the reconstruction of salinity. Process length variation of Lingulodinium machaerophorum has been used to reconstruct Black Sea salinity variation.