Zeauvigerina


Classification: pf_cenozoic -> Guembelitrioidea -> Heterohelicidae -> Zeauvigerina
Sister taxa: Rectoguembelina, Zeauvigerina,
Daughter taxa: - species ordered by first occurrence (blue => in age window 0-800Ma)
Distinguished from other zeauvigerinids by its more gently tapering test with a blunt initial end, more inflated adult chambers, necked aperture that is angled toward the apical axis rather than being terminal in position, and by lacking development of a uniserial final chamber.
Differs from other Eocene zeauvigerinids by lacking a produced neck and lip surrounding the terminal aperture. It further differs from Z. zelandica by its more elongate test that is parallel-sided for most of its length.
Distinguished from other zeauvigerinids by having a more elongate neck on the terminal uniserial chamber that is surrounded by a distinct rim.
The test variable in shape and size (150 - 370 µm), outline elliptical to moderately tapering, periphery rounded. Most specimens biserial with uniserial final chamber and terminal aperture on a short neck with surrounding lip. Less commonly biserial throughout, with off-centered interiomarginal aperture.
Distinguished from Z. parri and Z. waiparaensis by larger size and presence of a necked aperture, and from Z. zelandica by the absence of a rim around the terminal aperture.
Test elongate with very uniform chamber addition, biserial throughout. Aperture interiomarginal with equidimensional, thickened rim or lip.
The small, irregular outline of the test, uneven biserial chamber addition, and terminal, oval-shaped aperture on mature specimens distinguish this species. An equidimensional, narrow lip partially surrounds and folds into the aperture.
Specimens which cannot be assigned to established species

Taxonomy

Citation: Zeauvigerina Finlay, 1939, emended by Huber and Boersma, 1994
Rank: Genus
Type species: Zeauvigerina zelandica Finlay, 1939
Taxonomic discussion: There has been disagreement about the suprageneric classification of Zeauvigerina and whether or not this is a planktonic or benthic taxon. In his original description of this genus, Finlay (1939) noted similarities in chamber arrangement and morphology of the necked aperture between Zeauvigerina and the benthic taxon Eouvigerina and suggested a strong likelihood that these were closely related. Subsequently, Finlay (1947) noted that broken specimens of Z. teuria resemble Gu ½mbelina ( =Chiloguembelina) and suggested that Zeauvigerina was probably planktonic. A number of subsequent workers (e.g., Beckmann, 1957; Reiss, 1963; Jenkins, 1966, 1971) agreed with Finlay’s (1947) observations and considered Zeauvigerina to be closely related to Chiloguembelina. On the other hand, Loeblich (1951) emended the definition of Eouvigerina to accommodate Zeauvigerina as a junior synonym, and Loeblich and Tappan (1964) adopted this classification without considering Finlay’s (1947) revised interpretation. More recently, Loeblich and Tappan (1988) resurrected Zeauvigerina as a senior synonym but reallocated it to the benthic superfamily Loxostomatacea without explanation.
Huber and Boersma (1994) illustrated the “chiloguembelinid” morphology preserved within adult zeauvigerinid tests, but noted that this genus cannot be related to Chiloguembelina since (1) the earliest zeauvigerinid (Z. waiparaensis) precedes the early Danian origin of chiloguembelinids by several million years; and (2) the apertural lip in Chiloguembelina is inequally broadened and oriented to the side of the test, whereas the lips on immature specimens of Z. waiparaensis are uniformly thick, do not overlap on to the previous chamber, and the aperture is a smaller, semicircular arch oriented to the front of the test. They suggested that Z. waiparaensis was probably derived from Laeviheterohelix (Heterohelicidae) during the late Campanian or early Maastrichtian based on similarity of their wall textures and apertures of some Laeviheterohelix specimens.
It is not clear whether Zeauvigerina lived a planktonic or benthic mode of life. Oxygen and carbon isotope values of Z. waiparaensis plot much closer to co-occurring benthic species than planktonic species, yet its relative abundance in pelagic carbonate samples is greater than that of all benthic species combined (Huber and Boersma, 1994). The only oxygen isotope value obtained for Z. aegyptiaca is closer to a co-occurring benthic species than most co-occurring planktonic species (except Chiloguembelina strombiformis) yet its carbon isotope value suggests a planktonic habitat (Huber and Boersma, 1994). The limited geographic distribution of zeauvigerinids and restriction of some species to nearshore environments are not consistent with a dominantly planktonic mode of life. Further study of this group is needed to clarify its preferred depth habitat and determine if the zeauvigerinid clade is polyphyletic.
[Huber et al. 2006] Huber and Boersma (1994) emended the description of Zeauvigerina to accommodate the morphologic variation they observed in a biometric study of the genus.
[Huber et al. 2006]

Catalog entries: Zeauvigerina

NB These concise distinguishing features statements are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus.
They are being edited as the site is developed and comments on them are especially welcome.

Description


Wall type: wall microperforate, surface covered with irregularly scattered pustules on all but the final one or two chambers; [Huber et al. 2006]

Test morphology: Test small, subcircular to elliptical in cross-sectional outline; chambers biserially arranged in the early portion, with a tendency to become uniserial in the later portion, increasing gradually in size; sutures smooth to slightly depressed, horizontally or obliquely curved; aperture an asymmetrically positioned, low interiomarginal arched opening partially bordered by a narrow lip in the early ontogenetic stage, becoming oval-shaped and areally or terminally positioned in gerontic specimens, sometimes produced on a short neck that may or may not have an encircling lip.
[Huber et al. 2006]

Biogeography and Palaeobiology


Phylogenetic relations: Early Maastrichtian through late middle Eocene Zone E13 or E14.
[Huber et al. 2006]

Biostratigraphic distribution

Geological Range:
Notes: Early Maastrichtian through late middle Eocene Zone E13 or E14.
[Huber et al. 2006]
Last occurrence (top): in mid part of Priabonian Stage (48% up, 35.9Ma, in Priabonian stage). Data source: Total of range of species in this database
First occurrence (base): in mid part of Maastrichtian Stage (48% up, 69.2Ma, in Maastrichtian stage). Data source: Total of range of species in this database

Plot of occurrence data:

Primary source for this page: Huber et al. 2006 - Eocene Atlas, chap. 16, p. 478

References:

Finlay, H. J. (1939a). New Zealand foraminifera: Key species in stratigraphy - no. 1. Transactions of the Royal Society of New Zealand. 68: 504-533. gs

Finlay, H. J. (1947). New Zealand foraminifera: Key species in stratigraphy - no. 5. New Zealand Journal of Science and Technology. 28(5): 259-292. gs

Huber, B. T. & Boersma, A. (1994). Cretaceous origination of Zeauvigerina and its relationship to Paleocene biserial planktonic foraminifera. Journal of Foraminiferal Research. 24: 268-287. gs

Huber, B. T., Olsson, R. K. & Pearson, P. N. (2006). Taxonomy, biostratigraphy, and phylogeny of Eocene microperforate planktonic foraminifera (Jenkinsina, Cassigerinelloita, Chiloguembelina, Streptochilus, Zeauvigerina, Tenuitella, and Cassigerinella) and Problematica (Dipsidripella). In, Pearson, P. N. , Olsson, R. K. , Hemleben, C. , Huber, B. T. & Berggren, W. A. (eds) Atlas of Eocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication. 41: 461-508. gs

Jenkins, D. G. (1966b). Planktonic foraminiferal zones and new taxa from the Danian to lower Miocene of New Zealand. New Zealand Journal of Geology and Geophysics. 8: 1088-1126. gs

Loeblich, A. R. & Tappan, H. (1964b). Sarcodina, Chiefly "Thecamoebians" and Foraminiferida. In, Moore, R. C. (ed.) Treatise on Invertebrate Paleontology, Protista 2, pt. C. University of Kansas Press, Lawrence 1-900. gs

Loeblich, A. R. & Tappan, H. (1988). Foraminiferal Genera and Their Classification (Volume I-II). Van Nostrand Reinhold Co., New York. 1-1059. gs

Loeblich, A. R. (1951). Coiling in the Heterohelicidae. Contributions from the Cushman Foundation for Foraminiferal Research. 2: 106-110. gs

Reiss, Z. (1963). Reclassification of perforate foraminifera. Bulletin of the Geological Survey of Israel. 35: 1-111. gs


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Zeauvigerina compiled by the pforams@mikrotax project team viewed: 22-8-2019

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