CATALOG OF ORIGINAL DESCRIPTIONS: Globigerina hagni Gohrbandt 1967
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.
Original Description Test free, low-trochospirally coiled, equatorial periphery lobate, axial periphery rounded. Wall calcareous, perforate, surface pitted. Chambers spherical, somewhat ovate, 10-12, arranged in about two and one-half whorls, the last whorl with 4 chambers increasing moderately in size, the final chamber in fully adult specimens equal in size to or smaller than the penultimate cham ber. Sutures radial, slightly curved, moderately depressed. Umbilicus fairly narrow, moderately deep. Aperture a distinct slit at the base of the last chamber, extraumbilical-umbilical, covered in well-preserved specimens with a thin apertural lip. Size: Dimensions of holotype: Largest diameter 0.58 mm. Etymology: The species is harned in honor of Prof. Dr. H. Hagn, Munich, in recognition of his contributions to the micropaleontology of the Helvetikum. Extra details from original publication Remarks: This relatively large species of Globigerina is well-represented, with significant frequency in a number ofsamples. It is a very distinct form with its four somewhat compressed, globular chambers and the extraumbilical-umbilical aperture. The species was previously reported under the name Globigerina eocaena (Gumbel) by Subbotina (1953), from southern Russia. As mentioned by Hagn and Lindenberg (1966) the specimens determined as Globigerina eocanea by Subbotina are not that species, as described by Gumbel (1868). According to the revised description of Globigerina eocaena given by Hagn and Lindenberg, that species differs from Globigerina hagni by its more globular chambers and the umbilical position of the aperture. As suggested by its four compressed chambers and extraumbilicalumbilical aperture, Globigerina hagni might be the ancestor of Globigerina wilsoni Cole (= Globorotalia bolivariana (Petters) of Bolli, 1957b). Stratigraphic range: Globigerir1a hagni seems to be restricted stratigraphically to the lowest part of the Middle Eocene. Subbotina (1953) reported the species from southern Russia only from the "Zone of Acarininas." According to Berggren's (1966) correlation of Subbotina's zonation with that of Bolli from Trinidad (1957a, b) the "Zone of Acarininas" in Russia would correspond to the long interval from the Globorotalia palmerae Zone to the Globorotalia lehneri Zone of Bolli's zonation. Thus, the "Zone of Acarininas" comprises the uppermost part of the Lower Eocene and the main part of the Middle Eocene in Bolli's age-interpretation of the zones . In the type sample, Globigerina hagni is associated with Globigerina senni, G. ex gr. triloculinoides, G. aspensis, G. frontosa, G. eocaena, "Globigerinoides" higgensi, Clavigerinella akersi, G. jarvisi, Globanomalina wilcoxensis globulosa, Globorotalia aragonensis, G. mattseensis, G. bullbrooki, and G. spinuloinflata. In other samples with the same faunal association Hantkenina aragonensis was also found (see Hagn, 1960, pl. 5). This fauna compares well with the Hantkenina aragonensis Zone of the lowest part of the Middle Eocene, as defined by Bolli (1957b) in Trinidad. Globigerina hagni was first recognized in a biozone below the interval comprised at its type locality, characterized by Globorotalia wartsteinensis, and probably of Middle Eocene age. The present species was not observed in samples corresponding to the upper part of Bolli's ( l957b) Globigerapsis kugleri Zone (Gohrbandt, l963b, p. 54).
References:
Gohrbandt, K. H. A. (1967). Some new planktonic foraminiferal species from the Austrian Eocene. Micropaleontology. 13(3): 319-326. gs
Olsson, R. K., Hemleben, C., Huber, B. T. & Berggren, W. A. (2006a). Taxonomy, biostratigraphy, and phylogeny of Eocene Globigerina, Globoturborotalita, Subbotina, and Turborotalita. In, Pearson, P. N., Olsson, R. K., Hemleben, C., Huber, B. T. & Berggren, W. A. (eds) Atlas of Eocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication . 41(Chap 6): 111-168. gsVO
Globigerina hagni compiled by the pforams@mikrotax project teamviewed: 20-3-2023
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