Description of lectotype: The fairly small and globose test consists of about two whorls of chambers arranged in a fairly high and tightly coiled trochospire with 5 chambers present in the last whorl. The equatorial and axial profiles are subcircular and the equatorial periphery is weakly lobulate. The chambers are appressed, inflated, moderately embracing, reniform in dorsal aspect and ovoid in axial view. The sutures are moderately depressed. The umbilicus, although infilled, appears to be moderately broad. The primary aperture is obscured by the extraneous material present in the umbilicus but no indication exists that it is other than interiomarginal and umbilical. The wall is fairly thick, moderately and uniformly perforate and the surface of the test is practically smooth. [Banner & Blow 1960]

Taxonomic remarks: When d'Orbigny, in 1826, proposed the name Globigerina rotundata for forms obtained by him from the Island of Ste. Helene, he omitted to describe or figure the species or to give any other indication as to its nature. Consequently, the name G. rotundata d'Orbigny did not become taxonomically available until 1898 when Fornasini published for the first time copies of d'Orbigny's preliminary drawings of this species. In the A. d'Orbigny collections in Paris, one single specimen exists which was labelled "Globigerina rotundata d'Orbigny (Vivte ) Ste. Helene"" and the tube bearing the specimen was numbered ""12313"" on the reverse of its mount. This single specimen is here illustrated and designated as lectotype. Unfortunately the specimen is not well preserved and is very fragile and it did not prove possible to illustrate it in detail. It did not appear to be conspecific with the specimens obtained from Ravenna by Fornasini in 1899 which were referred by him to G. rotundata. The Fornasini specimens have no taxonomic availability except as potential neotypes (as they were obviously never seen by d'Orbigny) and so long as the d'Orbigny specimen exists they have no taxonomic status. [Banner & Blow 1960]

Remarks: The lectotype of G. rotundata is smaller than G. dutertrei d'Orbigny, and it appears to have fewer whorls of chambers. All its other morphological characters seem to agree with those of G. dutertrei and we consider the two forms synonymous. Globigerina rubra d'Orbigny, 1839 Plate 3, figures 8a, b [Banner & Blow 1960]

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