CATALOG OF ORIGINAL DESCRIPTIONS: Praeglobotruncana inermis Hasegawa 1999

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.

Higher levels: pf_cat -> P -> Praeglobotruncana -> Praeglobotruncana inermis
Other pages this level: P. algeriana, P. barbui, P. biconvexa gigantea, P. bronnimanni, P. clotensis, P. coarctata, P. compressa, P. crassa, P. gigantea, P. hagni, P. hansbollii, P. hessi compressiformis, P. hessi hessi, P. hilalensis, P. inermis, P. klausi, P. lehmanni, P. loeblichae, P. mattsoni, P. modesta, P. oraviensis, P. oraviensis trigona, P. pauliani, P. prahovae, P. primitiva, P. pseudoalgeriana, P. rohri, P. shirakinensis, P. stephani gibba

Praeglobotruncana inermis

Citation: Praeglobotruncana inermis Hasegawa 1999
Rank: Species
Type locality: Ohyubari area, Hokkaido, Japan; 43 degrees 2.60'N, 142 degrees 9.72'E
Type age (chronostrat): Uppermost Cenomanian
Type sample (& lithostrat): sample SRN 220, lower part of the Takinosawa Formation
Type specimens: Figs 6/1-4; Holotype IGPS 102704
Type repository: Tohoku, Japan; Institute of Geology & Paleontology, Tohoku University, Sendai, Japan
Described on page(s) : 183-184

Current identification/main database link: Praeglobotruncana inermis Hasegawa 1999

Original Description
Diagnosis.-A high trochospiral species of Praeglobotruncana with slight peripheral pustule lines, distinct lip near umbilicus and 4 smooth-walled chambers in last whorl.

Description.- Test of medium to large size, medium to high trochospiral, equatorial periphery lobulate ; chambers petaloidal in shape on dorsal side, trapezoidal to subglobular, inflated on dorsal side, about 12 in all arranged into 2 to 2.5 whorls, enlarging gradually in size as added, characteristically 4 chambers in final whorl, with a weak peripheral band formed of an aligned concentration of pustules which tends to be shifted toward spiral side ; final chamber shifted toward umbilical direction ; sutures on dorsal side radial and depressed except for that of first chamber in last whorl which occasionally is raised, ventrally radial and depressed; umbilicus shallow, medium to narrow in size, less than 1/4 of maximum diameter of test; primary aperture bordered by a distinct lip that expands markedly near umbilicus, interiomarginal, umbilical- extraumbilical ; wall calcareous, surface smooth, earlier chambers weakly pustulated

Size: Maximum diameter of holotype 0.34 mm, maximum thickness 0.21 mm.

Etymology: From Latin, inermis referring to the smooth-walled chambers of this species compared with other species of Praeglobotruncana

Extra details from original publication
Remarks.- This species closely resembles Praeglobotruncana anumalensis (Sigal), but differs in lacking the conspicuous pustules on earlier chambers, in having diagnostically 4 chambers in the last whorl, more lobulated periphery and more inflated chambers.


Hasegawa, T. (1999). Planktonic foraminifera and biochronology of the Cenomanian-Turonian (Cretaceous) sequence in the Ohyubari area, Hokkaido, Japan. Paleontological Research, Tokyo. 3: 173-192. gs


Praeglobotruncana inermis compiled by the pforams@mikrotax project team viewed: 28-1-2021

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