pforams@mikrotax - Globotruncana lapparenti pforams@mikrotax - Globotruncana lapparenti

Globotruncana lapparenti


Classification: pf_mesozoic -> Globotruncanidae -> Globotruncana -> Globotruncana lapparenti
Sister taxa: G. aegyptiaca, G. arca, G. bulloides, G. dalbiezi, G. dupeublei, G. esnehensis, G. falsostuarti, G. hilli, G. lapparenti, G. linneiana, G. mariei, G. neotricarinata, G. orientalis, G. rosetta, G. rugosa, G. ventricosa, G. sp.

Taxonomy

Citation: Globotruncana lapparenti Brotzen 1936, emended, Pessagno 1967
Taxonomic rank: species
Basionym: Globotruncana lapparenti
Synonyms:
Taxonomic discussion: Pessagno, 1967: The identification of this species has been hampered by the fact that Brotzen described it in syntypic series and cited numerous of de Lapparent's (1918) figures as syntypes. To stabilize the taxonomic status of G. lapparenti Brotzen, a lectotype (de Lapparent, 1918, op.cit., p. 5, tf. 2, fig. n) and a paralectotype (de Lapparent, 1918, op. cit., p. 5, tf. 2, fig. m) have been selected herein. Although a few of Brotzen's syntypes (de Lapparent, 1918, op. cit., p.4, tfs. 1, 3) are drawings of free specimens, the drawings are poor and hardly clarify the identification of C. lapparenti s. s. However, the drawings of de Lapparent's sectioned specimens are remarkably accurate in their detail and should leave little doubt concerning the identification of this species in thin-section. The specimens figured herein in pl. 71(figs. 6-13) correlate closely externally with the sectioned lectotype and paratype. The sectioned specimens figured in pl. 97 (particularly fig 9) herein are from the same horizon as the free specimens figured in pl. 71. [Pessagno 1967]

Type images:

Original description: Als neue Art muss die Formengruppe gelten, die Lapparent 1918 als Rosalina linnei beschrieb und bei der er mehrere Variationen unterscheiden konnte. Da weder der Typus noch die Variationen sich mit der Gl. linneiana d'Orb. decken, muss diese Form neu benannt werden. Ich schlage den Namen Globotruncana lapparenti n. sp. vor. Dieser Art gehren wahrscheinlich die von Cushman (1932, loc. cit.) gegebenen Gl. canaliculata-Formen an.

Entries in the Catalog of original descriptions: Globotruncana lapparenti, Globotruncana lapparenti inflata, Rosalinella lapparenti


Emended description:
Test trochospiral, somewhat spiroconvex (mean T'X/TX value for 19 specimens = 0.72), 5-6* chambers in final whorl, truncated peripherally by a well-developed double keel. Chambers spirally petaloid, separated by raised, beaded, curved sutures. Chambers umbilically, subrectangular, separated by elevated, raised curved sutures which are often beaded. Chamber surfaces exclusive of sutures usually lacking rugosities. Umbilicus relatively deep and covered by a spiral system of tegilla with intralaminal and infralaminal accessory apertures. Primary aperture, interiomarginal, umbilical in position. Outer wall radial hyaline, perforate except for keel which is both radial hyaline and ultragranular hyaline, imperforate. Septal walls and tegilla microgranular hyaline, finely perforate. [Pessagno, 1967]
* Pessagno's emended description actually says 4-5 chambers per whorl, but this appears to be typo since the specimens illustrated by Pessagno have 5-6 chambers in the final whorl, as do other illustrated specimens of the species. [BH Jun 2020, following comment of Chengje Liu]

Character matrix
test outline:Subcircularchamber arrangement:Trochospiraledge view:Equally biconvexaperture:Umbilical
sp chamber shape:Subtriangularcoiling axis:Moderateperiphery:Double keelaperture border:Tegilla
umb chbr shape:-umbilicus:Wideperiph margin shape:Subangularaccessory apertures:Intralaminal
spiral sutures:Raised beadedumb depth:Deepwall texture:Finely pustuloseshell porosity:-
umbilical or test sutures:-final-whorl chambers:5.5-7 N.B. These characters are used for advanced search. N/A - not applicable

Geological Range:
Last occurrence (top): within A. mayaroensis zone (67.64-69.27Ma, top in Maastrichtian stage). Data source: [copied from Chronos database]
First occurrence (base): within D. asymetrica zone (83.65-85.60Ma, base in Santonian stage). Data source: [copied from Chronos database]

Plot of range and occurrence data:

References:

Brotzen, F. (1936b). Foraminiferen aus dem Schwedischen Untersten Senon von Eriksdal in Schonen. Sveriges Geologiska Undersökning, Series C. (396): 1-206. gs

Caron, M. (1985). Cretaceous planktic foraminifera. In, Bolli, H. M., Saunders, J. B. & Perch-Nielsen, K. (eds) Plankton Stratigraphy. CUP, Cambridge 17-86. gs

Herb, R. (1974). Cretaceous planktonic foraminifera from the eastern Indian Ocean. Initial Reports of the Deep Sea Drilling Project. 26: 745-796. gs

Pessagno, E. A. (1967). Upper Cretaceous planktonic foraminifera from the western Gulf Coastal Plain. Palaeontographica Americana. 5: 245-445. gs O

Postuma, J. A. (1971). Manual of planktonic foraminifera. Elsevier for Shell Group, The Hague. 1-406. gs

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Globotruncana lapparenti compiled by the pforams@mikrotax project team viewed: 15-5-2026

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