Hantkenina liebusi


Classification: pf_cenozoic -> smooth non-spinose -> Hantkeninidae -> Hantkenina -> Hantkenina liebusi
Sister taxa: H. alabamensis, H. australis, H. compressa, H. dumblei, H. lehneri, H. liebusi, H. mexicana, H. nanggulanensis, H. primitiva, H. singanoae,

Taxonomy

Citation: Hantkenina liebusi Shokhina 1937
Rank: Species
Basionym: Hantkenina liebusi
Synonyms:
Taxonomic discussion: The first Hantkenina to be illustrated was Hantken’s ‘Siderolina kochi’. This may be a prior synonym for H. liebusi but the type specimen is lost and the original illustration is not definitive. When Shokhina (1937) described H. liebusi she specifically rejected Hantken’s figure as belonging to the same species. Although Shokhina’s specimens are also lost, she illustrated the morphology quite clearly and it is possible to make an almost exact match with specimens from the middle Eocene (see Plate 8.9) which is the level from which Shokhina described her species. The holotype of H. longispina Cushman resembles Shokhina’s illustrations of H. liebusi and may be a prior synonym. It has not been possible to compare the type specimens of these taxa because Shokhina’s H. liebusi material is unavailable for study and the type specimen of H. longispina is missing from the USNM collections. Moreover, H. longispina has been used indiscriminately for a variety of only distantly related Hantkenina morphotypes with ‘long’ tubulospines. Although the name H. longispina cannot be rejected on the grounds that it is an inappropriate name (ICZN, 1999, Art. 23.3.7), in an attempt to avoid further taxonomic confusion, and because the type specimen of H. longispina is lost, we propose that the name H. longispina be suppressed and H. liebusi adopted as the valid name for these middle Eocene morphotypes. Shokhina illustrated a large number of H. liebusi syntypes that clearly represent the range of morphology exhibited by this taxon. Since no holotype was designated we herein select Shokhina’s (1937) text-fig. 2 as the lectotype of H. liebusi and text fig. 8 as the paralectotype (Pl.8.9, Figs. 1-2). Blow (1979) did not recognise H. liebusi and instead assigned Shokhina’s (1937) morphotypes either to H. mexicana sensu lato or H. dumblei. We consider H. liebusi to be a useful species that is morphologically and stratigraphically intermediate between H. mexicana and H. dumblei. [Coxall & Pearson 2006]

Catalog entries: Hantkenina (Applinella) trinitatensis;
Hantkenina liebusi;
Siderolina kochi;

Type images:

Short diagnosis: Hantkenina liebusi shares features of wall texture, aperture and tubulospines with H. mexicana but differs in having a more compressed test, more closely appressed chambers and a less stellate peripheral outline. The tubulospines are also in a more forward position with respect to the radial chamber axis (i.e. there is a short anterior chamber-shoulder). Hantkenina liebusi usually has fewer chambers in the final whorl than H. dumblei and H. lehneri (4½-6, compared to 5-7 in the latter). It can be distinguished from H. dumblei by the slightly incised peripheral outline and shorter adult chambers and from H. lehneri in being generally less stellate.

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


Diagnostic characters: Hantkenina liebusi shares features of wall texture, aperture and tubulospines with H. mexicana but differs in having a more compressed test, more closely appressed chambers and a less stellate peripheral outline. The tubulospines are also in a more forward position with respect to the radial chamber axis (i.e. there is a short anterior chamber-shoulder). Hantkenina liebusi usually has fewer chambers in the final whorl than H. dumblei and H. lehneri (4½-6, compared to 5-7 in the latter). It can be distinguished from H. dumblei by the slightly incised peripheral outline and shorter adult chambers and from H. lehneri in being generally less stellate. [Coxall & Pearson 2006]

Wall type: Smooth, normal perforate probably nonspinose; tubulospines smooth or with spiral rifling, imperforate or perforated by small sparsely distributed pores with a well-defined zone of demarcation between the tubulospines and the chamber wall. [Coxall & Pearson 2006]

Test morphology: Planispiral, involute, biumbilicate and laterally compressed; 4-6 subtriangular chambers in the adult whorl, somewhat appressed, increasing rapidly in size as added; peripheral outline (excluding tubulospines) is slightly lobulate with minor incisions between chambers; each chamber of the final whorl extends into a hollow tubulospine; aperture is a narrow, elongated equatorial arch bordered by an imperforate lip that extends about two thirds up the apertural face, lip is often crenulated and/or pustulose along its margin; sutures are depressed, straight, becoming curved to slightly sigmoidal, remnants of earlier apertural lips are sometimes present along the sutures; tubulospines are constricted at the base, stout on early adult chambers, longer and more slender in final chambers, directed radially, positioned close to or at the anterior chamber suture, long posterior chamber shoulder and a minor or nonexistent anterior shoulder, terminating in finger-like projections (coronet structure of Ramsay, 1962) or tapering to a point, often with a tiny circular terminal aperture. [Coxall & Pearson 2006]

Size: Maximum shell diameter (excluding tubulospines) 0.48 mm (Shokhina, 1937). [Coxall & Pearson 2006]

Character matrix

test outline:Lobatecoiling axis:N/Achamber arrangement:Planispiralumbilicus:Wide
edge view:Compressedumbilical or test sutures:Moderately depressedspiral sutures:Moderately depressedshell porosity:Finely Perforate: 1-2.5
wall texture:Smoothaperture:Equatorialaperture border:Thin lipaccessory apertures:None
periphery:Tubulospinesumb chamber shape:Subtriangularsp chbr shape:Subrectangularperiph margin shape:Subangular
umb depth:Shallowdiameter mm:0.48width mm:breadth mm:
final-whorl chambers:4.0-6.0

Biogeography and Palaeobiology


Geographic distribution: Global distribution in the mid to low latitudes. Absent from high southern or northern latitudes (Stott and Kennett, 1990; Huber, 1991). [Coxall & Pearson 2006]
Aze et al. 2011 summary: Low to middle latitudes; based on Coxall & Pearson (2006)

Isotope paleobiology: Hantkenina liebusi has more positive ∂18O and negative ∂13C than Morozovelloides and has a similar isotopic signature to Turborotalia frontosa suggesting a relatively cold, deep habitat (Pearson et al, 1993, 2001; Coxall and others, 2000). [Coxall & Pearson 2006]
Aze et al. 2011 ecogroup 4 - Open ocean sub-thermocline. Based on very light δ13C and very heavy δ18O. Sources cited by Aze et al. 2011 (appendix S3): Pearson et al. (1993, 2001a); Coxall et al. (2000)

Phylogenetic relations: Hantkenina liebusi evolved from H. mexicana by forward progression of the tubulospine and closer appression of the chambers. It gave rise to H. lehneri and H. dumblei
by radial increase in chamber length and relaxation of the coiling to increase the number of chambers. In H. lehneri the chambers became elongate and the stellate peripheral outline was retained, whereas in H. dumblei the tubulospines moved forwards to span the anterior suture, and the periphery was smoothed. [Coxall & Pearson 2006]

Biostratigraphic distribution

Geological Range:
Notes: Middle Eocene Zones mid E8 to basal E13. [Coxall & Pearson 2006]
Last occurrence (top): within E13 zone (37.99-39.97Ma, top in Bartonian stage). Data source: Eocene Atlas
First occurrence (base): in lower part of E9 zone (20% up, 43.7Ma, in Lutetian stage). Data source: Wade et al. (2011), fig. 6

Plot of occurrence data:

Primary source for this page: Coxall & Pearson 2006 - Atlas of Eocene Planktonic Foraminifera, chapter 8, p. 238

References:

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.

Brönnimann, P., (1950). The Genus Hantkenina Cushman in Trinidad and Barbados, B. W. I. . Journal of Paleontology, 24(4): 397-420.

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.; Pearson, P.N.; Shackleton, N.J. & Hall, M.A., (2000). Hantkeninid depth adaptation: An evolving life strategy in a changing ocean. Geology, 28: 87-90.

Cushman, J.A., (1924). A new genus of Eocene foraminifera. Proceedings of the United States National Museum, 66(2567): 1-4.

Hantken, V.M., (1875). Die fauna der Clavulina szaboi-schichten. 1. Teil: Foraminifera. Mitteilungen aus dem Jahrbuch der ungarischen Geologischen Anstaalt, Budapest, 4: 1-93.

Huber, B.T., (1991). Paleogene and early Neogene planktonic foraminifer biostratigraphy of ODP Leg 119 Sites 738 and 744, Kerguelen Plateau (southern Indian Ocean). Proceedings of the Ocean Drilling Program, Scientific Results, 119: 427-449.

Liebus, A., (1911). Die foraminiferen fauna der mitteleocaenen Mergle von Norddal matlen. Sitzungsberichte der Kaiserlichen Akademie der Wissenschaften in Wien, Mathematisch-Naturwissenschaftliche Klasse, 120: 805-956.

Pearson, P.N.; Shackleton, N.J. & Hall, M.A., (1993). Stable isotope paleoecology of middle Eocene planktonic foraminifera and multi-species isotope stratigraphy, DSDP Site 523, South Atlantic. Journal of Foraminiferal Research, 23: 123-140.

Raju, D.S.N., (1968). Eocene-Oligocene planktonic foraminiferal biostratigraphy of Cauvery Basin, South India. Geological Society of India, 2: 286-299.

Ramsay, W.R., (1962). Hantkeninidae in the Tertiary rocks of Tanganyika. Contributions from the Cushman Foundation for Foraminiferal Research, 13: 78-89.

Rey, M., (1939). Distribution stratigraphique des Hantkenina dans le Nummulitique du Rharb (Maroc). Bulletin de la Société Géologique de France, 5: 321-341.

Shokhina, V.A., (1937). The genus Hantkenina and its stratigraphical distribution in the north Caucasus. Problems of Paleontology: 425-441.

Stainforth, R.M.; Lamb, J.L.; Luterbacher, H.; Beard, J.H. & Jeffords, R.M., (1975). Cenozoic planktonic foraminiferal zonation and characteristics of index forms. The University of Kansas Paleontological Contributions, 62: 1-425.

Stott, L.D. & Kennett, J.P., (1990). The Paleoceanographic and Paleoclimatic signature of the Cretaceous/Paleogene boundary in the Antarctic: Stable isotopic results from ODP Leg 113. Proceedings of the Ocean Drilling Program, Scientific Results, 113: 829-848.

Thalmann, H.E., (1942). Foraminiferal genus Hantkenina and its subgenera. American Journal of Science, 240: 809-820.


Hantkenina liebusi compiled by the pforams@mikrotax project team viewed: 28-6-2017

Taxon Search:
Advanced Search




Comments (0)

No comments yet. Be the first!

Add Comment

* Required information
1000
Captcha Image
Powered by Commentics