Catalog - Leupoldina protuberans

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.

Other pages this level: L. protuberans, L. pustulans hexacamerata

Leupoldina protuberans

Citation: Leupoldina protuberans Bolli 1957

Type specimens: holotype 2437, paratypes 2431-C 2436, 2438-C 2443. Unfigured paratypes deposited in the U. S. National Museum, Washington.

Type repository: Basel; Museum of Natural History,

Shape of test. - Early stage possibly very slightly trochospiral (usually not recognizable), later becoming planispiral, stellate. Wall. - Calcareous, finely perforate. Chambers. - Early chambers globular to subglobular, becoming more and more elongated; the early chambers of the last whorl each with a bulb- or bubble-shaped extension (often broken off). The final chamber, often also the penultimate and occasionally earlier chambers of the last whorl, with two, seldom three bulb-shaped extensions or protuberances, arranged symmetrically on each side of the equatorial plane. The final chamber with two protuberances may be almost severed along the equatorial plane. The last whorl consists of four to five chambers. Sutures. - Radial, depressed. Aperture.- In the early stage an interiomarginal, equatorial arch bordered by a thin lip. Ultimate chamber with two interiomarginal, umbilical apertures, one on each side of the chamber. Traces of probable relict apertures can occasionally be seen but as a rule seem to be absent. In some specimens the interiomarginal, equatorial aperture persists to the ultimate chamber, these might be taken as immature forms.

Largest diameter of holotype. -0,29 mm.

Observed stratigraphie range. - Aptian to Albian, ?Cenomanian.
Remarks - The forms included here in Leupoldina protuberans display considerable variation. The last whorl consists of four to five chambers. Although two is the usual number of protuberances per chamber, specimens with three (pl. II, figs. 12, 13) do occasionally occur. The multiple protuberances are in many specimens restricted to the ultimate chamber but they are often also present in the penultimate and even earlier chambers. Such differences might appear a sufficient basis for the establishment of number of subspecies. However, to justify such a subdivision it will have to be shown first that some or all of these features are not merely mutations which occur throughout the range of the species, but instead reflect evolutionary trends within the genus.

References:

Bolli, H. M. (1957c). The foraminiferal genus Schackoina Thalmann, emended, and Leupoldina, n. gen. in the Cretaceous of Trinidad, B. W. I. Eclogae Geologicae Helvetiae. 50(2): 271-278. gs

CATALOG OF ORIGINAL DESCRIPTIONS: Leupoldina protuberans Bolli 1957

Leupoldina protuberans

References:

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