CATALOG OF ORIGINAL DESCRIPTIONS: Truncorotaloides rohri Bronnimann & Bermudez 1953

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.


Higher levels: pf_cat -> T -> Truncorotaloides -> Truncorotaloides rohri
Other pages this level: T. haynesi, T. libyaensis, T. rohri, T. rohri guaracaraensis, T. rohri mayoensis, T. rohri piparoensis

Truncorotaloides rohri

Citation: Truncorotaloides rohri Bronnimann & Bermudez 1953
Rank: Species
Type locality: Duff road area, near Kelly junction, about seven miles east of Pointe-a-Pierre, central Trinidad.
Type sample (& lithostrat): sample K.R. 23842 - amarl pebble bed
Type specimens: Plate 87, figures 7-9; Holotype CC 172694
Type repository: Washington; USNM

Linked specimens: USNM-4233

Current identification/main database link: Acarinina rohri (Bronnimann & Bermudez 1953)


Original Description
"The low trochoidal test has a distinctly lobate outline. The spiral side, excepting the central portion, is almost flat and shows 2 volutions with about 13 chambers. The last whorl has 5 chambers. The early chambers are subglobular, appressed, the adult ones flat at the spiral side, subangular to angular and separated by strong peripheral incisions. The chambers of the final volution are overlapping. The umbilicus is deep and rather small. The sutures of the early portion of the test appear to be straight, the later ones are slightly curved in direction of coiling. The apertures of the last chambers are large arcute, open directly into the umbilicus, and are provided with minute lip-like borders. The preceding apertures are not visible. Small arcuate additional openings with minute lip-like growths pierce the spiral side of the last 2 chambers at the intersection of radial and spiral sutures. It is not known whether this type of opening is also present in the early ontogenic stage. The surface is ornamented with heavy spines, which are strongly developed on the initial chambers, on the pointed umbilical portions, and along the subangular edges of the adult chambers. The spines are rare and small in the vecinity of the apertures and on the flat spiral side of the last chambers. The walls are finely perforate. Seven out of eight specimens coil to the left.

Size: Maximum diameter of test 0.425 mm. End chamber: radial diameter 0.15 mm., tangential diameter 0.275 mm., height 0.250 mm. Diameter of aperture about 0.075 mm., of additional spiral open- ings 0.050 mm.

Etymology: The new species is named for K. Rohr in recognition of his contribution to the geology of the Central Range of Trinidad.

Extra details from original publication

Discussion: This form has been chosen as the central type of the group. it is intermediate between the angular and the sub-angular to rounded types. The test of Truncorotaloides rohri resembles somewhat Truncorotalia crassata (Cushman). However, paratypes of this species from Moctezuma River, Hacienda Romance, State of Vera Cruz, Mexico, collected by Earl Oliver, kindly lent for comparison by theU. S. National Museum, do not possess additional sutural openings; the same is true for specimens of T. crassata (Cushman) from the Guayabal formation, Mexico, obligingly donated by W. Storrs Cole, Ithaca

References:

Berggren, W. A., Pearson, P. N., Huber, B. T. & Wade, B. S. (2006b). Taxonomy, biostratigraphy, and phylogeny of Eocene Acarinina. In, Pearson, P. N., Olsson, R. K., Hemleben, C., Huber, B. T. & Berggren, W. A. (eds) Atlas of Eocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication. 41(Chap 9): 257-326. gs V O

Bolli, H. M., Loeblich, A. R. & Tappan, H. (1957). Planktonic foraminiferal families Hantkeninidae, Orbulinidae, Globorotaliidae and Globotruncanidae. In, Loeblich, A. R. , Jr., Tappan, H., Beckmann, J. P., Bolli, H. M., Montanaro Gallitelli, E. & Troelsen, J. C. (eds) Studies in Foraminifera. U.S. National Museum Bulletin. 215: 3-50. gs V O

Brönnimann, P. & Bermudez, P. J. (1953). Truncorotaloides, a new foraminiferal genus from the Eocene of Trinidad, B.W.I. Journal of Paleontology. 27: 817-820. gs


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Truncorotaloides rohri compiled by the pforams@mikrotax project team viewed: 30-7-2021

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