pforams@mikrotax - Paraticinella rohri

Citation: Paraticinella rohri (Bolli 1959)

Basionym: Praeglobotruncana rohri

Synonyms:

Ticinella roberti var. eubejaouaensis
Paraticinella eubejaouaensis
Ticinella bejaouaensis Sigal, 1966, auctt [the holotype of T. bejaouaensis is a different species, but almost all usage of the species name follows the concept adopted here - see taxonomic discussion]

Taxonomic discussion: This species has previously been known as Ticinella bejaouaensis, or latterly T. eubejaouaensis, but Ando et al. (2013) have now definitively established the correct name as P. rohri Bolli 1957.

From Ando et al. (2013) abstract: The planktonic foraminiferal taxon Ticinella bejaouaensis Sigal, 1966 had long been an important zonal biomarker for the latest Aptian characterized by its large test, numerous (8-10) final-whorl chambers, and rugose test surface, usually with an umbilical cover-plate. Upon confirmation that Sigal’s Madagascan holotype was actually from the upper Albian, this species was renamed as T. eubejaouaensis Randrianasolo and Anglada, 1998 using Sigal’s Tunisian bejaouaensis paratype, which is late Aptian in age, as the new holotype. Following emendation of the genus, Paraticinella eubejaouaensis has recently become the standard usage. However, the validity of this species is still uncertain because the original designation was given in very obscure publication(s). Meanwhile, albeit tenuous, a presumable senior name “Paraticinella rohri (Bolli, 1959)” has recently been proposed in place of eubejaouaensis. Rigorous assessment of the original species designation of T. eubejaouaensis ascertains that the method of publication used does not comply with the criteria required in the International Code of Zoological Nomenclature, thereby making this species an invalid name, or nomen nudum. New backscattered scanning electron microscopic observations of the primary types of Praeglobotruncana rohri Bolli, 1959 reveal that this hitherto unattended species is indeed synonymous to “T. eubejaouaensis” particularly by exhibiting equatorially aligned rugosities on the wall surface, and that the holotype is sufficiently preserved and well qualified as the name-bearing type. The latest Aptian age of the rohri type level is robustly established by its co-occurrence with Pseudoplanomalina cheniourensis (Sigal, 1952) and Hedbergella trocoidea (Gandolfi, 1942) (¼ another rohri paratype). Upon confirmation of the absence of any potential nomenclatural acts for conservation of the junior name “[eu]bejaouaensis,” we are obliged to provide formal redescription and establish the valid, objective senior name Paraticinella rohri (Bolli, 1959), the binomen that should be of mandatory use henceforth. Accordingly, the uppermost Aptian “[eu]bejaouaensis” Zone should be referred to as the “Pt. rohri Zone. Having reviewed the supraspecific taxonomy, herein the type species of the genus Paraticinella is redefined as Pt. rohri, and the subfamily Pseudoplanomalininae is proposed.

Original description: Shape of test low trochospiral, equatorial periphery slightly lobate, axial periphery rounded. Wall calcareous, finely compressed on the anterior and posterior ends; twenty to twenty-five chambers, arranged in three whorls; the seven to nine chambers of the last whorl increase moderately in size. Sutures radial, depressed on spiral and umbilical side. Umbilicus fairly narrow, deep. Aperture a long, medium to low arch with a rim above, interiomarginal, umbilical-extraumbilical. Coiling, ratio of dextral to sinistral coiling approximately 2:1.

Premoli Silva et al., 2009: New description of Sigal's paratype. Test a low, almost flat trochospire, 9 globular chambers in the outer whorl, increasing very gradually in size, separated by radial straight depressed sutures throughout on both sides; the last chamber is slightly displaced toward the umbilicus; in edge view, chambers globular in shape; wall surface rugose except in the last three chambers, with distinctive rugosities concentrated on the inner spire and on both sides of the first chambers of the last whorl, forming an irregular network of short ridges paralleling the equatorial periphery, gradually attenuating in the last four chambers; on the early chambers, there are perforation cones visible at high magnification with the stereomicroscope; primary aperture an interiomarginal low-medium arch, umbilical-extraumbilical in position; in the last two chambers, two large triangular labial flaps extend over the umbilicus; their surface is slightly depressed in the middle and slightly raised at the margin as a gentle rim readily visible, especially in the last one; the two flaps are fused, but the suture line, slightly depressed, remains visible; two small depressions filled with sediment, apparently in correspondence with the sutures, may mark the location of two small infralaminal openings.

Geological Range:
Last occurrence (top): at top of P. rohri zone (100% up, 113.2Ma, in Albian stage). Data source:
First occurrence (base): at base of P. rohri zone (0% up, 116.6Ma, in Aptian stage). Data source:

References:

Ando, A., Huber, B. T. & Premoli Silva, I. (2013). Paraticinella rohri (Bolli, 1959) as the valid name for the latest Aptian zonal marker species of planktonic foraminifera traditionally called bejaouaensis or eubejaouaensis. Cretaceous Research. 45: 275-287. gs

Bolli, H. M. (1959c). Planktonic foraminifera from the Cretaceous of Trinidad, B. W. I. Bulletins of American Paleontology. 39(179): 253-277. gs

Leckie, M. (1984). Mid-Cretaceous planktonic foraminiferal biostratigraphy off Central Morocco, Deep Sea Drilling Project Leg 79, Sites 545 and 547. Initial Reports of the Deep Sea Drilling Project. 79: 579-620. gs

Lipson-Benitah, S. & Almogi-Labin, A. (2004). Aptian planktonic foraminifera from Israel. Israel Journal of Earth Sciences. 53(1): 27-46. 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. (2): 1-298. gs

test outline:	Subcircular	chamber arrangement:	Trochospiral	edge view:	Inequally biconvex	aperture:
sp chamber shape:	Subrectangular	coiling axis:	Low	periphery:	N/A	aperture border:	Thin lip
umb chbr shape:	Subtriangular	umbilicus:	Wide	periph margin shape:	Broadly rounded	accessory apertures:	None
spiral sutures:	Moderately depressed	umb depth:	Deep	wall texture:	Coarsely costate	shell porosity:
umbilical or test sutures:	Moderately depressed	final-whorl chambers:	6-9	N.B. These characters are used for advanced search. N/A - not applicable

Paraticinella rohri

References:

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