CATALOG OF ORIGINAL DESCRIPTIONS: Fingeria praeglobotruncaniformis Georgescu 2011

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 -> F -> Fingeria -> Fingeria praeglobotruncaniformis
Other pages this level: F. praeglobotruncaniformis

Fingeria praeglobotruncaniformis

Citation: Fingeria praeglobotruncaniformis Georgescu 2011
Rank: Species
Type locality: DSDP Site 95, Sample 10-95-15-2, 73-87 cm (upper Santonian, lower part of the D. asymetrica Bio- zone).
Type age (chronostrat): Upper Santonian (lower part of D. asymetrica Biozone).
Type specimens: Holotype.– WKB 010128. Paratypes.– Five specimens, WKB 010129-010133
Type repository: Willi Karl Braun Micropaleontological Collection at the University of Calgary (Calgary, Alberta, Canada)

Current identification:


Original Description

Diagnosis.– Fingeria species with axially compressed last-formed chambers and subangular to truncate periphery.

Description.– Test medium-high to high trochospiral, consisting of 14 to 19 chambers arranged in 2 ½ to 3 ½ whorls; there are 5 ½ to 6 ½ (mostly 6) chambers in the final whorl (Pl. 5, Figs 7, 9-10, 12, Pl. 6, Figs 1, 3, 6, 8). Earlier chambers are globular, those of the last whorl petaloid to subtrapezoidal on the spiral side (Pl. 5, Figs 7,10, Pl. 6, Figs 1, 6) and subtrapezoidal and axially compressed, with low size increase on the umbilical side (Pl.5, 9, 12, Pl. 6, Figs 3, 8). Sutures are depressed throughout, straight or slightly curved on both test sides; sutures on the spiral side are perpendicular to oblique to the previous whorl (Pl. 5, Figs 7, 10, Pl. 6, Figs 1, 6), those on the umbilical side radial (Pl. 5, 9, 12, Pl. 6, Figs 3, 8). Test asymmetrical in edge view, with a strongly convex spiral side and slightly concave umbilical side (Pl. 5, Figs 8, 11, Pl. 6, Figs 2, 7). Periphery is broadly rounded in the earlier stage and subangular to truncate in the adult; a weak keel consisting of agglomerated pustules is often developed at the periphery of the penultimate whorl and earlier chambers of the final whorl (Pl. 5, Figs 7, 10, Pl. 6, Fig. 6). Aperture is a medium-high arch, extraumbilical-umbilical in position and bordered by a triangular imperforate triangular flap (Pl. 5, Figs 9, 12, 14, Pl. 6, Figs 3-4, 8). Umbilicus is deep and medium-sized, with a diameter representing approximately one third to one half of the test maximum diameter; relict periapertural structures occur in the umbilical region (Pl. 5, Figs 9, 12, 14, Pl. 6, Figs 3-4, 8). Chamber surface is ornamented with scat- tered dome-like pustules (6.2-16.3 µm), which can fuse to form short rugosities (20.1-25.8 µm in length) or, more rarely, costellae (24.2-32.3 µm in length); ornamentation occasionally has a meridional pattern on the umbilical side and parallel to the periphery pattern on the spiral side (Pl. 5, Figs 7, 9-10, 12, 15, Pl. 6, Figs 1, 3-5, 8). Test wall is calcitic, hyaline, simple or with ridged appearance and perforate; pores are circular, with a diameter of 1.1-4.2 µm.


Size: Dimensions.– Dmax=0.370-0.434 mm; Dmin=0.345-0.404; Dmin/Dmax=0.847-0.932; T=0.182-0.234 mm; T/Dmax=0.434-0.539; UD=0.137-0.194; UD/Dmax=0.323-0.484. Average ranges based on the measurements of 12 specimens: holotype, paratypes and topotypes.

Etymology: The suffix “-formis” is added to the genus name Praeglobotruncana, suggesting its praeglobotruncanid appearance.

Extra details from original publication

Remarks.– Fingeria praeglobotruncaniformis differs from F. loetterlei and F. kingi by having (i) axially compressed last- formed chambers, (ii) a weak keel developed on the penultimate whorl and the earlier chambers of the last whorl and (iii) ornamentation that present occasionally has meridional and parallel to the periphery patterns on the umbilical and spiral side respectively. It differs from B. turbinata by (i) the occasionally developed ornamentation patterns on the spiral and umbilical sides, (ii) less developed peripheral keel and (iii) larger umbilicus, which in the adult specimens represents approximately one half of the maximum test diameter. Hedbergella flandrini Porthault in Donze et al., 1970 is a coeval species that re- sembles F. praeglobotruncaniformis  in the axially compressed chambers. The morphological  differences between the two taxa are major and the former species presents (i) very low to low rather medium-high to high trochospire, (ii) simple periphery rather than lined with a weak keel, (iii) aperture bordered by an imperforate lip rather than an imperforate triangular flap, (iv) narrower umbilici  and (v) ornamentation consisting of scattered dome-like pustules rather than a combination of pustules, rugosities and costellae with asymmetrical pattern; for these reasons H. flandrini belongs to the hedbergellid stock.

References:

Georgescu, M. D. (2011b). Iterative evolution, taxonomic revision and evolutionary classification of the praeglobotruncanid planktic foraminifera, Cretaceous (late Albian-Santonian). Revista Española de Micropaleontología. 43: 173-207. gs V O


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Fingeria praeglobotruncaniformis compiled by the pforams@mikrotax project team viewed: 30-7-2021

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