pforams@mikrotax - Trinitella pforams@mikrotax - Trinitella


Classification: pf_mesozoic -> Rugoglobigerinidae -> Trinitella
Sister taxa: Archaeoglobigerina, Bucherina, Kuglerina, Plummerita, Rugoglobigerina, Rugotruncana, Trinitella
Daughter taxa (time control age-window is: 0-800Ma)
Trinitella scotti

Trinitella suturis
The test usually has 7 chambers in the last whorl and raised and curved spiral sutures. Two rows of rugosities form a double keel on the final chambers.
Trinitella sp.
Specimens which cannot be assigned to established species


Citation: Trinitella Brönnimann 1952
taxonomic rank: Genus
Type species: Trinitella scotti Brönnimann, 1952

Original description: Test trochoidal, elongate in direction of end chamber. Chambers truncate at apertural side, increasing in size as added (end chamber about twice the size of the penultimate one), subglobular in major portion of adult whorl, flattened at the spiral side and peripherally keeled in the end stage. Chambers arranged in about 2 whorls, those of the last volution overlapped by the preceding ones. Sutures on the spiral side curved in direction of coiling, those on the umbilical side more or less straight to slightly curved backward. Umbilicus large, subcircular, with fragments of covering plate along truncate edges of chambers. Aperture large, elongate-arcuate, with minute liplike projection leading into the umbilicus. Wall apparently thick, surface coarsely rugose, especially in earlier chambers. Ornamentation suggesting a variant of the meridional pattern of Rugoglobigerina.

Entries in the Catalog of original descriptions: Trinitella

Distinguishing features:
Parent taxon (Rugoglobigerinidae): Test trochospiral, chambers inflated, periphery rounded, not carinate; wall with pustules, costellae, or other rugosities; aperture umbilical, with portici or tegilla.
This taxon: Test in flat trochospiral, chambers enlarging rapidly as added, early ones globular, later chambers compressed to rhomboidal in section, imperforate carinal band or faint keel in the final whorl, sutures radial, depressed, peripheral margin rounded to truncate, peripheral outline lobulate; wall calcareous, perforate, surface covered with prominent pustules and costellae in meridional arrangement, less prominent on the final chamber; primary aperture interiomarginal, umbilical, bordered by an imperforate flap, those of successive chambers fusing into a tegillum having both proximal and distal accessory apertures.

Geological Range:
Last occurrence (top): at top of P. hariaensis zone (100% up, 66.4Ma, in Maastrichtian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within G. gansseri zone (71.73-73.80Ma, base in Campanian stage). Data source: Total of ranges of species in this database

Plot of range and occurrence data:


Loeblich, A. R. & Tappan, H. (1988). Foraminiferal Genera and Their Classification (Volume I-II). Van Nostrand Reinhold Co., New York. 1-1059. gs


Trinitella compiled by the pforams@mikrotax project team viewed: 13-7-2024

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