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Emended Description of Cycloputeolina discoidea (=Peneroplis pertusus var. discoideus Flint, 1899 ( anglais )

fourni par EOL authors

Cycloputeolina discoidea has a planispiral, discoidal test. The juvenile stage is involutely coiled with curved chambers. The coiling then shifts from an involute mode to an evolute mode. Successive chambers are flabelliform and reniform in shape. The final ontogenetic stage is comprised of annular, or ring-shaped, chambers. The involute stage is biconvex and lenticular in shape with a keeled periphery. Subsequent stages are biplanar and compressed. Chambers are greater in width than height and of relatively uniform height. The chamber surface is slightly inflated. Randomly distributed pseudopores cover the entire chamber surface at a density of 6-8 pits per 100 µm3 of test surface area. The interior of the chambers is undivided, and lacks septa, walls or pillars.

There are multiple apertures per chamber. The apertures are round to oval in shape and bordered by a round, elevated, imperforate rim. The apertural face is ornamented with irregularly shaped, haphazardly dispersed pseudopores. A single row of apertures is present along the periphery of the last-formed chambers.

licence
cc-by-nc-sa-3.0
droit d’auteur
Susan L. Richardson
citation bibliographique
Richardson, Susan L. 2014. Cycloputeolina discoidea. Diagnostic Description: Emended description of Cycloputeolina discoidea (=Peneroplis pertusus var. discoideus Flint, 1899), http://eol.org/pages/27481610/details
auteur
Susan Richardson (SLRichardson)
original
visiter la source
site partenaire
EOL authors

Type Description of Cycloputeolina discoidea (=Peneroplis pertusus var. discoideus Flint, 1899 ( anglais )

fourni par EOL authors

Cycloputeolina discoidea was originally described and figured by Flint (1899: p. 304, pl. 49, figs. 1, 2) as a variety of Peneroplis pertusus. The original description is as follows: “In this variety the final chambers completely surround the primary convolutions, forming a circular, thin disk resembling the discoidal forms of Orbulina, but distinguished by the entire absence of septa in the individual chambers.”

licence
cc-by-nc-sa-3.0
droit d’auteur
Susan L. Richardson
citation bibliographique
Bibliographic citation: Richardson, Susan L. 2014. Cycloputeolina discoidea. Diagnostic Description: Type description of Cycloputeolina discoidea (=Peneroplis pertusus var. discoideus Flint, 1899), http://eol.org/pages/27481610/details
auteur
Susan Richardson (SLRichardson)
original
visiter la source
site partenaire
EOL authors