CATALOG OF ORIGINAL DESCRIPTIONS: Rugotruncana ellisi Bronnimann&Brown 1956
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.
Citation: Rugotruncana ellisi Bronnimann&Brown 1956taxonomic rank: SpeciesType specimens: 628611Type age (chronostrat): MaastrichtianType locality: Navarro Group, Corsicana Marl; from an exposure along a branch of Mustang Creek, 1.0 mi. west-southwest of Noack, 900 feet south from the Taylor-Noack Road and 0.2 mi. southwest of Christ Evangelical Lutheran Church in Williamson County, central TX, USA.Type repository: Washington; USNM
Original Description The low trochospirally coiled test is covered with an incipient development of costellae. All chambers are inflated and globigerine-like, but later ones show a slight degree of compression. The last whorl is scalloped and composed of 5-6 chambers. Some or all later chambers exhibit a very weak double-keeled, imperforate, peripheral band. The 2 keels are very faint and may be missing from a few of the last chambers. The costellae which are barely discernible, give the surface a roughened appearance. The principal aperture is rounded, interiomarginal, and open into a rather large umbilicus. Long apertural flaps extend into the umbilicus, and in later chambers form a protruded, imperforate, umbilical cover-plate with accessory apertures. Etymology: This species is named for Brooks F. Ellis in recognition of his contributions to micropaleontology. Extra details from original publication Remarks:Rugotruncana ellisi, n. sp., is the most primitive species of Rugotruncana. It resembles the genotype, Rugotruncana tilevi, n. sp., but its chambers are not as compressed, and it keels and costellae are weaker. It is similar to Globotruncana saratogaensis (Applin), but the latter has no costellae.
Rugotruncana ellisi, n. sp., has been observed by us in the upper Taylor marl (Campanian). It is abundant in the Corsicana marl (lower Maastrichtian) and Kemp clay (middle Maastrichtian) of the Navarro group in Texas, and in the Arkadelphia formation of the Navarro group in Arkansas.
Range: Campanian to Maastrichtian.
References:
Brönnimann, P. & Brown, N. K. (1956). Taxonomy of the Globotruncanidae. Eclogae Geologicae Helvetiae. 48: 503-562. gsO
Rugotruncana ellisi compiled by the pforams@mikrotax project teamviewed: 16-10-2024