Clavigerinella


Classification: pf_cenozoic -> smooth non-spinose -> Hantkeninidae -> Clavigerinella
Sister taxa: Cribrohantkenina, Hantkenina, Clavigerinella,
Daughter taxa (blue => in age window 0-300Ma)
Final chambers with bulbous terminal swellings
Final chambers taper into an acute or pointed tip
Final chambers paddlewheel-like, i.e. flattened in side view, sub-triangular in edge view
Final chambers smoothly rounded, clavate
Final chambers elongate and slender, without terminal swellings
Specimens which cannot be assigned to established species

Taxonomy

Citation: Clavigerinella Bolli, Loeblich and Tappan, 1957
Rank: Genus
Type species: Clavigerinella akersi Bolli, Loeblich and Tappan, 1957.
Synonyms:
Taxonomic discussion: We unite all Eocene morphotypes that possess clavate chambers in the genus Clavigerinella with the exception of the early Eocene form Parasubbotina prebetica, which has a low trochospiral coiling mode (Chapter 5, Olsson and others, this volume). Previously there has been a lack of agreement over the appropriate generic designation; some authors have united all Eocene digitate forms in Clavigerinella (Banner and Blow, 1959; Blow, 1979; Banner, 1982; Toumarkine and Luterbacher, 1985; Pearson, 1993; Coxall and others, 2003), whereas others distinguish both Hastigerinella and Clavigerinella spp. because several species (eocanica, jarvisi, caucasica and colombiana) were originally placed in the modern digitate genus Hastigerinella (e.g., Saito and others, 1976; Loeblich and Tappan, 1988). The dichotomy can be traced to a dispute over the validity and original authorship of the type species of Hastigerinella, i.e., modern Hastigerina digitata Rhumbler, 1911, and the question of whether or not it should be replaced by Eocene Hastigerinella eocanica (the second named species of Hastigerinella), which would fundamentally change Cushman’s (1927) original concept of Hastigerinella. In order to obtain a formal resolution on this matter and stabilize the taxonomy of Clavigerinella the case was brought to the International Commission on Zoological Nomenclature (Coxall, 2003). The Commission proposed that Hastigerina digitata Rhumbler, 1911 should be included on the list of valid species and thus be maintained as the type species of Hastigerinella, in accordance with the view of Banner and Blow (1959), Banner (1982) and Hemleben and others (1989). This leaves Clavigerinella legally available as the generic name for stratigraphically and phylogenetically linked Eocene digitate forms that have an entirely different wall texture to (and, thus, are unrelated to) modern Hastigerinella digitata.
The taxonomy and stratigraphic range of Clavigerinella is difficult to assess because of their patchy geographical and stratigraphic distribution. Concentrations of Clavigerinella spp. occur in regions that were probably associated with high biological productivity due to upwelling during the Eocene. We acknowledge that there is a range of variability in chamber morphology within and between individuals, but in contrast to Blow (1979) who recognised only two species of Clavigerinella, we have identified five distinct morphotypes based on chamber shape and character of the chamber terminations that may be of geographic, stratigraphic or phylogenetic significance.
As observed by Blow (1979) the wall of Clavigerinella spp. is usually smooth but like its ancestor Parasubbotina eoclava it can also be weakly cancellate with a sacculifer-like underlying structure. Hemleben and Olsson (Chapter 4, this volume) have designated this wall texture as the Clavigerinella-type wall. The question of whether or not Clavigerinella was spinose in life is still unresolved. Cushman believed that Hastigerinella jarvisi ( =Clavigerinella jarvisi) had spines at the ends of the chambers, as in its modern homeomorph Hastigerinella digitata. Scanning electron micrographs of the holotype of this species (Pl. 8.2, Figs. 14-18) do not, however, support this. There is possible evidence of spine holes in material from the Helvetikum section in Austria (see Hemleben and Olsson, Chapter 4, this volume). There is as yet no good evidence, however, of spines in the descendent group Hantkenina, so presumably the spines were lost at some stage in the evolution.
There are at least 15 other digitate species from the Cretaceous, Paleogene and Neogene that are broadly comparable in overall morphology to Clavigerinella but are probably unrelated. Clavigerinella is restricted to the latest early to late Eocene and all earlier and subsequent digitate species are regarded as independently evolved homeomorphs. Species of Clavigerinella, particularly C. akersi, C. colombiana and C. jarvisi, are usually rare in tropical pelagic assemblages. However, they occasionally occur in relatively large numbers in association with species of Paragloborotalia, Parasubbotina and Pseudoglobigerinella, e.g., in Colombia, Peru, the Ivory Coast (ODP Site 960), Endeavour Seamount (Kane 9-C Piston core), the equatorial Pacific (ODP Site 1218) and the western equatorial Atlantic (ODP Site 1258). These localities, which are mainly western continental margins, equatorial zones and oceanic seamounts were probably regions of upwelling during the Eocene. This suggests Clavigerinella spp. were specialized to high-productivity environments (Coxall, 2000).
[Coxall & Pearson 2006]

Catalog entries: Clavigerinella;

Type images:

Short diagnosis: Final chambers clavate.

NB The short diagnoses are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus. They have initially been copied from the diagnostic characters/distinguishing features sections of the Eocene and Paleocene Atlases, they will be edited as the site is developed.

Description


Wall type: Weakly cancellate or smooth, normal perforate, possibly sparsely spinose. [Coxall & Pearson 2006]

Test morphology: Planispiral or pseudo-planispiral coiling, 4-5 chambers in the final whorl, increasing rapidly in size as added; final 2-3 chambers elongate, becoming clavate (club-shaped) or digitate (finger-like); distal chamber ends may be inflated, compressed or paddle-shaped with rounded, bulbous, or pointed terminations; aperture is an elongated equatorial arch aperture bordered by a distinctive flaring lip. [Coxall & Pearson 2006]

Biogeography and Palaeobiology


Phylogenetic relations: Clavigerinella was descended from Parasubbotina inaequispira via the intermediate morphospecies P. eoclava. It gave rise to tubulospinose Hantkenina by gradual morphological transition in the latest early Eocene (Coxall and others, 2003). Hantkenina singanoae n. sp. is the transitional species that bridges the morphological and stratigraphic gap between clavate and tubulospinose morphologies. [Coxall & Pearson 2006]

Most likely ancestor: Parasubbotina - at confidence level 4 (out of 5). Data source: Coxall & Pearson (2006), fig 8.1.

Biostratigraphic distribution

Geological Range:
Notes: Uppermost lower Eocene to the upper Eocene. [Coxall & Pearson 2006]
Last occurrence (top): near top of Priabonian Stage (90% up, 34.3Ma, in Priabonian stage). Data source: Total of range of species in this database
First occurrence (base): near top of Ypresian Stage (85% up, 49.1Ma, in Ypresian stage). Data source: Total of range of species in this database

Plot of occurrence data:

Primary source for this page: Coxall & Pearson 2006 - Atlas of Eocene Planktonic Foraminifera, chapter 8, p. 216

References:

Banner, F.T. & Blow, W.H., (1959). The classification and stratigraphical distribution of the Globigerinaceae. Paleontology, 2(1): 1-27.

Banner, F.T., (1982). A classification and introduction to the Globigerinacea. Aspects of Micropaleontology (papers presented to Professor Tom Barnard). Allen and Unwin, London, 142-239 pp.

Blow, W.H., (1979). The Cainozoic Globigerinida: A study of the morphology, taxonomy, evolutionary relationships and stratigraphical distribution of some Globigerinida (mainly Globigerinacea). E. J. Brill, Leiden, 1413 pp.

Campos 1980 [sorry, not in our bibliography yet]

Coxall, H.K. & Pearson, P.N., (2006). Taxonomy, biostratigraphy, and phylogeny of the Hantkeninidae (Clavigerinella, Hantkenina and Cribrohantkenina). In: Pearson, P.N. et al. (Editors), Atlas of Eocene Planktonic Foraminifera, Cushman Foundation Special Publication 41. Allen Press, Lawrence, Kansas, pp. 213-256.

Coxall, H.K., (2000). Hantkeninid planktonic foraminifera and Eocene palaeoceanographic change. PhD Thesis, University of Bristol, unpublished, 264 pp.

Coxall, H.K., (2003). Hastigerinella Cushman, 1927 and Clavigerinella Bolli, Loeblich & Tappan, 1957 (Rhizopodea, Foraminiferida): proposed conservation of the usage by designation of Hastigerina digitata Rhumbler, 1911 as the type species of Hastigerinella. Bulletin of Zoological Nomenclature, 60: 182-186.

Coxall, H.K.; Huber, B.T. & Pearson, P.N., (2003). Origin and morphology of the Eocene planktonic foraminifera Hantkenina. Journal of Foraminiferal Research, 33: 237-261.

Cushman 1927 Mexican Mexican [sorry, not in our bibliography yet]

Loeblich, A.R., Jr. & Tappan, H., (1957). Planktonic foraminifera of Paleocene and early Eocene Age from the Gulf and Atlantic coastal plains. In: Loeblich, A.R., Jr. et al. (Editors), Studies in Foraminifera, U.S. National Museum Bulletin 215. U.S. Government Printing Office, Washington, D.C., pp. 173-198.

Loeblich, A.R. & Tappan, H., (1957). Woodringina, a new foraminiferal genus (Heterohelicidae) from the Paleocene of Alabama. Journal of the Washington Academy of Sciences., 47: 39-40.

Loeblich, A.R., Jr. & Tappan, H., (1988). Foraminiferal Genera and Their Classification (Volume I-II). Van Nostrand Reinhold Co., New York, 1059 pp.

Pearson, P.N., (1993). A lineage phylogeny for the Paleogene planktonic foraminifera. Micropaleontology, 39: 193-232.

Rhumbler, L., (1911). Die Foraminiferen (Thalamophoren) der Plankton-Expedition: Teil 1. Die allgemeinen Organisations verhaltnisse der Foraminiferen, Plankton Expedition Humbold-Stiftung, Ergeben 3, L. C 1, 331 pp.

Saito, T.; Thompson, P.R. & Breger, D., (1976). Skeletal ultra-microstructure of some elongate-chambered planktonic foraminifera and related species. Progress in Micropaleontology, Special Publication. Micropaleontology Press, The American Museum of Natural History, New York, 278-304 pp.

Toumarkine, M. & Luterbacher, H., (1985). Paleocene and Eocene planktic foraminifera. Plankton Stratigraphy. Cambridge Univ. Press, Cambridge, 87-154 pp.


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Clavigerinella compiled by the pforams@mikrotax project team viewed: 13-12-2017

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