Chiloguembelina ototara

Classification: pf_cenozoic -> microperforate -> Chiloguembelinidae -> Chiloguembelina -> Chiloguembelina ototara
Sister taxa: C. cubensis, C. ototara, C. parallela, C. trinitatensis, C. wilcoxensis, C. crinita, C. subtriangularis, C. midwayensis, C. morsei, C. sp.,


Citation: Chiloguembelina ototara Finlay 1940
Rank: Species
Basionym: Guembelina ototara
Taxonomic discussion: Hornibrook (1990) was the first to draw attention to the significant difference in wall texture between topotypes of C. cubensis, which are striate, and topotypes of C. ototara, which have pustules that are randomly distributed on the test surface rather than striae. These differences are apparent in SEM images but they are difficult to discern under the light microscope. Guembelina cubensis Palmer var. heterostoma Bermúdez and Guembelina venezuelana Nuttall var. rugosa Parr may be prior synonyms but their wall textures are currently undetermined. [Huber et al. 2006]

Catalog entries: Guembelina cubensis heterostoma;
Guembelina ototara;
Guembelina venezuelana rugosa;

Type images:

Short diagnosis: Test short to somewhat elongate, moderately to rapidly expanding, subtriangular, periphery rounded rather than compressed; usually 11-12, up to 15 chambers; sutures depressed, perpendicular to slightly oblique to growth axis; Aperture moderately narrow to broad symmetrical arch centered or slightly off-center, bordered on one side by a narrow lip.

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.


Diagnostic characters: Distinguished from C. cubensis by the absence of striae on the wall surface and the shorter, more strongly tapering test, and from S. martini by its more inflated chambers and lower apertural arch. [Huber et al. 2006]

Wall type: Microperforate, uniformly finely pustulose, lacking pore mounds or costae. [Huber et al. 2006]

Test morphology: Test short to somewhat elongate, moderately to rapidly expanding, subtriangular in outline, periphery rounded rather than compressed; chambers biserial, increasing moderately to rapidly in size, usually 11-12, and sometimes up to 15 in adult specimens; sutures depressed, perpendicular to slightly oblique to growth axis; aperture a moderately narrow to broad symmetrical arch centered or slightly off-center of the base of the final chamber, extending half-way up the final chamber face, bordered on one side by a narrow lip that thickens away from its attachment point on the chamber face. [Huber et al. 2006]

Size: Paratype USNM 689102: length, 0.17 mm, width 0.10 mm, breadth 0.07 mm; hypotypes up to 0.23 mm length, 0.9 mm breadth. [Huber et al. 2006]

Character matrix

test outline:Triangularchamber arrangement:Biserialedge view:aperture:
umb chamber shape:coiling axis:periphery:aperture border:
sp chbr shape:umbilicus:periph margin shape:accessory apertures:
umbilical or test sutures:umb depth:wall texture:shell porosity:
spiral sutures:diameter mm:width mm:breadth mm:
final-whorl chambers:2.0-2.0

Biogeography and Palaeobiology

Geographic distribution: Cosmopolitan. [Huber et al. 2006]

Isotope paleobiology: Stable isotope data obtained for upper Eocene C. ototara (Barrera and Huber, 1991; identified as Chiloguembelina spp.) suggest that it lived near the surface mixed layer at high southern latitudes. [Huber et al. 2006]

Phylogenetic relations: Probably descended from Chiloguembelina crinita during the early middle Eocene. [Huber et al. 2006]

Most likely ancestor: Chiloguembelina crinita - at confidence level 4 (out of 5). Data source: Huber et al. 2006, f16.2.

Biostratigraphic distribution

Geological Range:
Notes: Middle Eocene Zone E9 through lower Oligocene Zone O1. The lowest and highest occurrences of this species are difficult to determine because of its morphologic similarity to its presumed ancestor, C. crinita, and its likely descendant, C. cubensis. A lowermost Oligocene (Zone O1) extinction of this species was recorded in New Zealand (Hornibrook, 1990) and ODP Sites 806 and 807 on Ontong Java Plateau (Resig, 1993). [Huber et al. 2006]
Last occurrence (top): within O1 zone (32.10-33.90Ma, top in Rupelian stage). Data source: Huber et al. 2006, f16.2
First occurrence (base): within E9 zone (43.23-43.85Ma, base in Lutetian stage). Data source: Huber et al. 2006, f16.2

Plot of occurrence data:

Primary source for this page: Huber et al. 2006 - Atlas of Eocene Planktonic Foraminifera, chapter 16, p. 474


Barrera, E. & Huber, B.T., (1991). Paleogene and early Neogene oceanography of the southern Indian Ocean: Leg 119 foraminifer stable isotope results. Proceedings of the Ocean Drilling Program, Sci. Res., 119: 693-717.

Bermudez, P.J., (1937). Nuevas especies de Foraminiferos del Eoceno de las cercanias de Guanajay, provincia Pinar del Rio, Cuba. Memorias de la Sociedad Cubana de Historia Natural, 11(4): 237-248.

Finlay, H.J., (1940). New Zealand foraminifera: Key species in stratigraphy - no. 4. Transactions of the Royal Society of New Zealand, 69(4): 448-472.

Hornibrook, N.d.B., (1990). Chiloguembelina cubensis (Palmer) and C. ototara (Finlay), in New Zealand. Journal of Foraminiferal Research, 20(4): 368-371.

Huber, B.T., (1991). Paleogene and Early Neogene Planktonic Foraminifer Biostratigraphy of Sites 738 and 744, Kerguelen Plateau (Southern Indian Ocean). Proceedings of the Ocean Drilling Program, Scientific Results, 119: 427-449.

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. et al. (Editors), Atlas of Eocene Planktonic Foraminifera, Cushman Foundation Special Publication 41. Cushman Foundation Special Publication.41 Allen Press, Lawrence, Kansas, pp. 461-508.

Hussey, K.M., (1949). Louisiana Cane River Eocene foraminifera. Journal of Paleontology, 23: 109-144.

Jenkins, D.G. & Srinivasan, M.S., (1985). Cenozoic planktonic foraminifera from the Equator to the Sub-Antarctic of the Southwest Pacific. Initial Reports of the Deep Sea Drilling Project, 90: 795-834.

Jenkins, D.G., (1971). New Zealand Cenozoic Planktonic Foraminifera. New Zealand Geological Survey, Paleontological Bulletin, 42: 1-278.

Palmer, D.K., (1934). The Foraminiferal Genus Guembelina in the Tertiary of Cuba. Memorias de la Soc. Cubana de Historia Natural, 8(2): 73-76.

Parr, W.J., (1938). Upper Eocene Foraminifera from Deep Borings in King's Park, Perth, Western Australia. Journal of the Royal Society of Western Australia, 24: 69-101.

Resig, J.M., (1993). Cenozoic stratigraphy and paleoceanography of biserial planktonic foraminifers, Ontong Java Plateau. In: Berger, W.H. et al. (Editors), Proceedings of the Ocean Drilling Program, Scientific ResultsOcean Drilling Program, College Station, Texas, pp. 231-244.


Chiloguembelina ototara compiled by the pforams@mikrotax project team viewed: 20-2-2018

Taxon Search:
Advanced Search

Go to to create a permanent copy of this page - citation notes

Comments (0)

No comments yet. Be the first!

Add Comment

* Required information
Captcha Image
Powered by Commentics