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.
Test free, medium in size for the genus, moderately high trochospire, equatorial profile ovoid, equatorial periphery slightly lobulate; axial profile suboval, axial periphery broadly rounded; chambers rounded, inflated, fairly rapidly and almost uniformly increasing in size, four chambers making up each whorl, in all three whorls visible; intercameral sutures depressed, increasingly so during the ontogeny, becoming almost incised between the last few chambers; only two apertures present on the test exterior; primary aperture interiomarginal, a low intraumbilical arch, often with a narrow rim; single spiral supplementary sutural aperture, small hole or crescent-shaped opening with no rim, situated at the junction of the last intercameral suture and spiral sutures; wall calcareous, thick, markedly cancellate and punctate.
Size: Maximum diameter of holotype 0.32 mm; paratype (fig. 4a-b) 0.28 mm; paratype (fig. 6a-b) 0.32 mm.
Extra details from original publication
Remarks: This species is closely related to forms referred by workers to Globigerinoides trilobus (REUSS), G. quadrilobatus (D'ORBIGNY) and G. sacculifer (BRADY), together with various combinations of these names and so-called subspecies. It is distinguished as a separate species because of its single spiral supplementary aperture and a rather high trochospiral test for the genus. There is considerable morphological resemblance between this species and Globigerina woodi JENKINS, although the former has a distinct supplementary aperture and, therefore, belongs to the genus Giobigerinoides.
This species has so far been found only in the Nishikurosawa Formation and very little is known about its stratigraphic range and geographic distribution.
Globigerinoides japonicus compiled by the pforams@mikrotax project team viewed: 21-4-2021
Short stable page link: https://mikrotax.org/pforams/index.php?id=130854 Go to Archive.is to create a permanent copy of this page - citation notes