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Sphaerozoum crassus Goll, 1980

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Axial rod 42-65µm long, 8-12µm in diameter, circular in cross section. Two or four simple spines, approximately equal in length to the axial rod, radiate in equi-angular clusters from each end of tr axial rod. All surfaces of the axial rod and spines bear a profusion of minute spines or nodes.
There is a trend in this species towards increasing thickness of the skeletal elements with time. Skeletons of the oldest specimens are slender and are distinguished from other sphaeroids by their micronodular texture. In addition to being thick-walled, the peripheries of the skeletal elements of younger specimens have a double image, giving the impression of being hollow. This image may result from regular arrangement of the nodes in longitudinal rows, however.
This species has an abrupt extinction level in the EPR sites. Other younger sphaeroids, such as Rhaphidozoum acuferum bear spicules, but S. crassus is distinguished from these species by its much smaller size.
Goll 1980











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