CATALOG OF ORIGINAL DESCRIPTIONS: Globigerina inaequispira var. transversa Khalilov 1956
This page provides data from the catalog of type descriptions. The catalog is sorted alphabetically. Use the current identification link to go back to the main database.
Citation: Globigerina inaequispira var. transversa Khalilov 1956Rank: VarietyDescribed on page(s) : 241Type specimens: pl . 2 , fig. 4a-cType age (chronostrat): Middle EoceneType locality: NE Azerbaidzhan S.S.R. Type repository: Baku; Geological Institute, Academy of Sciences, Baku, Azerbaijan
Current identification:
Original Description Translation from the Russian. - Test low conical, convex at the periphery of the penultimate chamber. Test consists of two whorls; in the first whorl there are five small chambers, and in the second there are four inflated chambers, of which the last one is oblique in relation to the preceding chambers. Test suboval, low conical, periphery broadly lobate. The periphery of the last and the penultimate chambers is convex. Dorsally, a relatively large initial chamber is surrounded by five spherical chambers of the first whorl, which increase rapidly in size. In the second whorl there are four large, spherical chambers. The first whorl is usually in the same plane as the second whorl, producing a moderate convexity. Ventrally, there are four inflated chambers, the anterior part of the last slightly deflecting from the horizontal plane of coiling; its anterior po r tion being markedly displaced toward the ventral side, it assumes an oblique position in relation to the preceding horizontal chambers. Septal sutures narrow, straight, less frequently weakly curved , depressed. Aperture curved, slitlike, on the last chamber . Wall calcareous, relatively densely pitted. Size: Diameter 0.61 mm.; thickness 0.21 mm. Extra details from original publication Comparison. - The most variable feature of the present species is the degree of deflection of the last chamber in relation to the horizontal plane of coiling. This deflection quite often reaches 45 degrees, due to which the outline of the last chamber varies from subspherical to markedly compressed. Our form differs from the typical Globigerina inaequispira Subbotina, from the middle Eocene of the Northern Caucasus, in the oblique position of the final chamber in relation to the horizontally-arranged preceding chambers. It is not excluded that this variety might be erected as a separate species. Holotype from the northeastern Azerbaidzhan S.S.R. Found also in the foothills of the Maly Caucasus, Nakhichevan A.S.S.R., and in the Maly Balkhan, Turkmen S.S.R.
References:
Khalilov, D. M. (1956). 0 pelagicheskoy faune foraminifer Paleogenovykh otlozheniy Azerbaydzhana [Pelagic Foraminifera of the Paleogene Deposits of the Azerbaizhan SSR]. Trudy Instituta Geologii, Akademiya Nauk Azerbaidzhanskoi SSR. 17: 234-255. gs
Globigerina inaequispira transversa compiled by the pforams@mikrotax project teamviewed: 5-6-2023
holotype illus_901.jpg
holotype illus_901.jpg
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