Catalog - Paraticinella

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.

Paraticinella

Citation: Paraticinella Premoli Silva et al., 2009

Type species: Ticinella eubejaouaensis Randrianasolo and Anglada, 1998, and Ticinella bejaouaensis as emended by Moullade, 1966

Low trochospiral, generally slightly lobate in outline, numerous chambers (7–11) in the last whorl, globular, sutures straight and depressed on both sides; wall finely perforate; wall surface rugose to smooth, with rugosities masking the inner whorl, then covering the first chambers of the last whorl, frequently organized in irregularly sized ridges that may cover the pores and run parallel to the spiral suture; surface of later-formed chambers may bear volcano-like perforation cones that progressively attenuate toward the ultimate chamber; shallow umbilical area moderate to large in size; umbilical area may be covered, at least partially, by large flaps from the ultimate and penultimate chambers that fuse along a slightly depressed line forming a cover-plate; primary aperture an interiomarginal arch, umbilical-extraumbilical extending toward the periphery; may have one to two small, weakly developed umbilical accessory (infralaminal) apertures in the last chambers.

Distinguishing features. Paraticinella n. gen. is highly convergent in morphology with true Ticinella. The major differences between these two genera are wall textures: presence of perforation cones that coalesce to form irregular imperforate ridges paralleling the coiling direction in finely perforate Paraticinella, instead of single muricae and absence of any ridge patterns as in normally perforate Ticinella; and lack of true umbilical supplementary apertures in the new genus.

Remarks. Paraticinella differs from the genus Ticinella in having the wall surface covered by smaller pores and perforation cones that coalesce to form irregular imperforate ridges on earlier chambers and toward the periphery that may mask the small, dense perforations and that may grow as ridges in patterns paralleling the coiling direction of the inner spire and the equatorial outline; evolutionarily advanced specimens contain well-developed flaps merging into a cover-plate and may contain one to two weakly developed infralaminal accessory apertures bordered by a thin rim. In Ticinella, rugosities on the wall surface form from pointed muricae that grow as irregularly distributed larger pustules surrounding large perforations, and there are at least two well-developed supplementary apertures bordered by rims in the umbilical area, which may remain open or lightly covered by weakly developed portici. It is worth mentioning that Longoria (1974, p. 93) re-emended the genus Ticinella Reichel 1950, emended Brönnimann and Brown 1956, in order to summarize the characters he used for distinguishing Ticinella bejaouaensis Sigal.

Stratigraphic range. Uppermost Aptian; the extension into the lowermost Albian, as reported in the literature (i.e., Moullade, 1966; Sigal, 1966; Moullade and others, 2002), cannot be proven in the absence of the formal definition for the base of the Albian stage (Aptian/Albian boundary).

The original description appears to define two type species, however this is a reflection of the history of the species concerned. The text should probably be read as "type species; Ticinella eubejaouaensis Randrianasolo and Anglada, 1998 = T. bejaouaensis sensu Moullade 1966" [editor's comment - JRY 2019]

References:

Brönnimann, P. & Brown, N. K. (1956). Taxonomy of the Globotruncanidae. Eclogae Geologicae Helvetiae. 48: 503-562. gs O

Longoria, J. F. (1974). Stratigraphic, morphologic and taxonomic studies of Aptian planktonic foraminifera. Revista Española de Micropaleontología. Numero Extraordinario: 5-107. gs

Moullade, M. (1966). Etude stratigraphique et micropaleontologique du Crétacé inférieur de la "fosse vocontienne". Document des Laboratoires de Géologie de la Faculté des Sciences de Lyon. 15: 1-369. gs

Premoli Silva, I., Caron, M., Leckie, R. M., Petrizzo, M. R., Soldan, D. & Verga, D. (2009). Paraticinella n. gen. and taxonomic revision of Ticinella bejaouaensis Sigal, 1966. Journal of Foraminiferal Research. 39: 126-137. gs

Randrianasolo, A. & Anglada, R. (1998). About Ticinella roberti var. bejaouaensis Sigal 1966 and Ticinella bejaouaensis Sigal emended Moullade 1966. La Habana. 1-298. gs

Reichel, M. (1950). Observations sur les Globotruncana du gisement de la Breggia (Tessin). Eclogae Geologicae Helvetiae. 42: 591-617. gs O

CATALOG OF ORIGINAL DESCRIPTIONS: Paraticinella Premoli Silva et al., 2009

Paraticinella

References:

Add Comment

Comments