Taxon Concept provided by
  Home |   Search

Click on a letter below to get a list of species:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z all
Hantkenina australis Finlay 1939 from: Pearson, P.N.Olsson, R.K.Hemleben, C.Huber, B.T.Berggren, W.A. (2006): Atlas of Eocene Planktonic Foraminifera. p. 1-513
.
Anonymous: Unedited TaxonConcept data
Notice: This catalogue page may contain unedited data.

Species Hantkenina australis Finlay 1939


Alternative name:
Diagnosis / Definition:
Pearson et al. (2006):
DESCRIPTION. Type of wall: Smooth, normal perforate, probably nonspinose; average pore size is often smaller than in other species of Hantkenina; tubulospines imperforate, smooth or with spiral rifling. Test morphology: Planispiral, laterally compressed with 5-6 closely appressed subtriangular chambers in the final whorl; peripheral outline lobed or slightly angular, anterior chamber shoulder is minimal or non-existent; most or all of the adult chambers extend into a hollow tubulospine; primary aperture is an equatorial high arch extending about halfway up the apertural face, widening towards the base into weak basal lobes and bordered on each side by an imperforate lip; sutures depressed, straight or slightly sigmoidal; pustules common on early chambers of the final whorl and in the umbilical region; tubulospines slender, often long, curved backwards slighily in the opposite direction to coiling, tapering to a poiilt, arising sharply from the supporting chamber, positioned at or just spanning the anterior chamber suture, sometimes partially contacting the adjacent younger chamber. Size: Maximum diameter without spines: 0.45 mm, with spines, 0.56 mm (Jenkins, 1965).
Discussion / Comments:
Jenkins (1985):
H. australis is distinguished from other species of the genus by recurved spines. It is found sporadically in the Middle Late Eocene Globigerinatheka index Globorotalia inconspicua zones in New Zealand. The only other good record of H. australis is in the early Middle Eocene of DSDP Leg 40 Site 362A in the South Atlantic (Tournarkine, 1978).
Pearson et al. (2006):
DISTINGUISHING FEATURES.- This species has a variable test morphology, showing features of H. dumblei and H. compressa. It differs froin both, and all other species of Hantkenina in having posteriorly recurved tubulospines. DISCUSSION.- Finlay (1939) did not provide a detailed description or designate a type specimen when he erected this species because the available specimens were incomplete. He stated that the holotype would be figured later when new material was found and instead figured a paratype from a different locality. This specimen differs significantly from the type description in lacking recurved tubulospines and having a more angular outline. Jenkins (1965) produced the first detailed description of H. australis and selected a type specimen out of the six incomplete specimens from Finlay's original sample that satisfactorily represents the taxon. This specimen is illustrated in SEM for the first time (Pl. 8.5, Figs. 1-2). Brönnimann (1950) and Ramsay (1962) recorded H. australis in Trinidad and Tanzania respectively but in both cases the identification was based on Finlay's paratype and the illustrated specimens do not have recurved tubulospines. Our concept of H. australis is based on Finlay's (1939) and Jenkins's (1965) notion of a form with backward curving tubulospines. Subbotina's (1953) illustrations of 'Hantkenina alabamensis' clearly show this distinctive feature. We have found this species in correlatable sequences hom the southern Labrador Sea (ODP Site 647), Uzbekistan, southern Russia and the Ukraine (Beniamovski, pers. comrn., 2001), indicating that it has a global distribution. It appears to be most common at the high southerly and northerly extremes of the hantkeninid latitudinal range suggesting it was more tolerant of cold water than other hantkeninids. In parallel with the H. dmmblei-H. compressa-H. alahamensis transition, there is a tendency for the test to become more inflated through time. Hantkenina compressa coexists with H. australis in the upper middle Eocene in New Zealand. A common feature of this taxon is for tubulospines to be absent on the early chambers as in H. primitiva, which makes it impossible to distinguish between them when the tubulospines are missing. PHYLOGENETIC RELATIONSHIPS.- Probably evolved from H. dumblei in the middle Eocene. STRATIGRAPHIC RANGE.- Middle Eocene, Zones Ell-E13. GEOGRAPHIC DISTRIBUTION.- Global, low to mid latitudes, most common at the high northerly and southerly extremes of the hantkeninid range, i.e., New Zealand, southern Labrador Sea. STABLE ISOTOPE PALEOBIOLOGY.- No data available.
Systematics:

35
 Ordo Foraminiferida
  Superfamilia Globigerinaceae
   Familia Hantkeninidae
    Genus Hantkenina
     Species Hantkenina alabamensis
Synonym list:
Jenkins (1985):
1939 Hantkenina australis Finlay. - Finlay : p.538
1985 Hantkenina australis Finlay. - Jenkins : p.273 figs. 6.16; 5
Pearson et al. (2006):
1939 Hantkenina australis Finlay. - Finlay : p.538 pl. 56; fig. 20, 21 [middle Eocene, Hampden, New Zealand]
1942 Hantkenina (Hantkenina) australis Finlay. - Thalmann : p.811 (listed only)
non 1950 Hantkenina (Hantkenina) australis Finlay. - Brönnimann : p.413 pl. 56; fig. 20, 21 [upper Eocene, Oceanic Fm., Barbados]; (=H. alabamensis).
1953 Hantkenina alabamensis Cushman. - Subbotina : p.146 pl. 1; fig. 6-7 [upper Eocene, northern Caucasus, Russia]; [Not Cushman, 1925]
non 1962 Hantkenina (Hantkenina) australis Finlay. - Ramsay : p.83 pl. 16; fig. 10 [middle Eocene, Kitunda Bluffs, Lindi, Tanganyika, Sample WA 1981]
1965 Hantkenina australis Finlay. - Jenkins : p.518 fig. 1, 2 [late middle Eocene, Hampden, New Zealand, sample F5 179B
2006 Hantkenina australis Finlay. - Pearson et al. : p.231 pl. 8.5; fig. 1-15 (Pl. 8.5, Figs. 1-2: new SEMs of the holotype of Hantkenina australis Finlay)
Was used in synonym list of:
Specimen:
New Zealand Geological Survey Collection - Lower Hutt, New Zealand, Inventory number: 103211
New Zealand Geological Survey Collection - Lower Hutt, New Zealand, Inventory number: 103213
New Zealand Geological Survey Collection - Lower Hutt, New Zealand, Inventory number: F5601
New Zealand Geological Survey Collection - Lower Hutt, New Zealand, Inventory number: 1035/4-6
References:

Finlay,H.J. (1939):
New Zealand foraminifera; key species in stratigraphy, No. 3 . Transactions of the Royal Society of New Zealand Vol. 69 p. 309-29

Finlay,H.J. (1939):
New Zealand foraminifera; key species in stratigraphy, No. 1 . Transactions of the Royal Society of New Zealand Vol. 68

Thalmann,H.E. (1942):
Foraminiferal genus Hantkenina and its subgenera . American Journal of Sciences Vol. 240 p. 809-823

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

Subbotina,N.N. (1953):
Fossil foraminifera of the USSR. Globigerinidae, Hantkeninidae and Globorotaliidae [in Russian] . Trudy Vsesoyuznogo Neftyanogo Nauchno-Isledovatelskogo Geologo-Razvedochnogo Instituta (VNIGRI), Novaya Seriya Vol. 76 p. 1-296

Ramsay,W.R. (1962):
Hantkenininae in the Tertiary rocks of Tanganyika . Contributions from the Cushman Foundation for Foraminiferal Research Vol. 13 p. 79-89

Jenkins,D.G. (1965):
The genus Hantkenina in New Zealand . New Zealand Journal of Geology and Geophysics Vol. 8 p. 518-526

Jenkins,D.G. (1985):
Southern mid-latitude Paleocene to Holocene planktic foraminifera.
In: Plankton stratigraphy Eds: Bolli, H.M.Saunders, J.B.Perch-Nielsen, K. p. 263-282

Pearson,P.N.; Olsson,R.K.; Hemleben,C.; Huber,B.T. and Berggren,W.A. (2006):
Atlas of Eocene Planktonic Foraminifera. p. 1-513
Anonymous: Unedited TaxonConcept data
Creative Commons Attribution 2.5 License
This work is licensed under a Creative Commons Attribution 2.5 License.