arrayname: original
Taxonomy
Original description: Test convex on the dorsal side, double-keeled, subcircular with a narrow peripheral band; the second keel only slightly shifted toward the umbilicus; chambers becoming long, arched, elongated in the adult stage, sutural elevations thinner than in Glt. lapparenti lapparenti, but continuously raised on the umbilical side, running with sigmoidal development, but bending sharply back and tending to attach themselves to the previous ones. The last ones sometimes still plunge within the umbilical cavity. The test is generally smooth; the umbilical cavity is large with thin, long, nearly straight apertural lips. The specimens investigated are dextrally coiling.
Entries in the Catalog of original descriptions: Globotruncana fornicata manaurensis
Character matrix
test outline: | Circular | chamber arrangement: | Trochospiral | edge view: | Equally biconvex | aperture: | Umbilical |
sp chamber shape: | Crescentic | coiling axis: | Low | periphery: | Double keel | aperture border: | Thin lip |
umb chbr shape: | Crescentic | umbilicus: | Wide | periph margin shape: | Subangular | accessory apertures: | None |
spiral sutures: | Raised | umb depth: | Shallow | wall texture: | Finely muricate | shell porosity: | Finely Perforate: 1-2.5µm |
umbilical or test sutures: | Raised beaded | final-whorl chambers: | 5-5.5 | N.B. These characters are used for advanced search. N/A - not applicable |
Geological Range:
Last occurrence (top): within D. asymetrica zone (83.65-85.60Ma, top in Santonian stage). Data source:
First occurrence (base): within M. schneegansi zone (89.75-92.51Ma, base in Turonian stage). Data source:
Plot of range and occurrence data:
Gandolfi, R. (1955). The genus Globotruncana in northeastern Colombia. Bulletins of American Paleontology. 36: 1-118. gsReferences:
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Marginotruncana manaurensis compiled by the pforams@mikrotax project team viewed: 25-4-2025
Short stable page link: https://mikrotax.org/pforams/index.php?id=110586 Go to Archive.is to create a permanent copy of this page - citation notes |
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Comments (2)
Citation: Marginotruncana manaurensis Gandolfi 1955 brackets missing
corrected, thanks