Original Description Translation from the Russian. - Test large (0.4-0.5 mm.), dorsal side flattened and ventral side very high, oval: a) coefficient of elongation around 1.2; b) coefficient of broadening 1.3-1.5. Structure of initial part globigerinoid, low-trochoid. Number of chambers in initial part 6-8. 3.5 rapidly enlarging chambers in the last whorl. Half-chamber takes part in building the last whorl. First chamber spherical, second one oval or subquadrate. very broad and long. extended beyond the outline of the test, its width is equal to the width of the last chamber or somewhat larger (coefficient around 1-1.1); last chamber also very long and broad (ratio of length to width 1-1.1). Outer margin of last chamber broadly rounded, its form is sub-spherical or oval. Last chamber often shifted toward the umbilicus. Chambers of last whorl an anged freely. Intercameral sutures oblique or curved, thin, deep. Outer margin coarsely scalloped. Umbilical depression narrow (when the last chamber shifts toward the first one, see tf. 5, fig. 11) to broad. Apertural opening marginal, short, extends from the center of the test to the begin- ning of the outer margin as an open slit lying below the overhanging margin of the last chamber. Perforation frequent, coarse. Size: Etymology: Extra details from original publication Variation. - The last chamber sometimes abuts right against the entire first chamber without formation of an umbilicus. The shape of the last chamber can be completely spherical, but is more often oval.
Comparison. - Differs from Globigerina compressaeformis Khalilov by: 1) the widthwise extension of the penultimate chamber; 2) the oblique sutures; 3) the coarsely scalloped outer margin; 4) the larger dimensions. Editors' Notes
Shutskaya, E. K. (1970a). Morphologic groups and descriptions of species of Globigerina and Acarinina in the lower Paleogene of the Crimea, the Caucasus Foreland, and western Central Asia. Trudy Vsesoyuznego Neftyanogo Nauchno-Issledovatel 'skogo Geologo-Razvedochnogo Instituta (VNIGRI). 69: 79-113. gs
Globigerina contorta compiled by the pforams@mikrotax project teamviewed: 4-12-2022