CATALOG OF ORIGINAL DESCRIPTIONS: Acarinina pseudosubsphaerica Pearson & Berggren, in Berggren et al. 2006

This page provides data from the catalog of type descriptions. The catalog is sorted alphabetically. Use the current identification link to go back to the main database.

Higher levels: pf_cat -> A -> Acarinina -> Acarinina pseudosubsphaerica
Other pages this level: << < A. intermedia, A. interposita, A. kiewensis, A. mattseensis alticonica, A. mcgowrani, A. microsphaerica, A. multicamerata, A. multiloculata, A. pentacamerata acceleratoria, A. pentacamerata camerata, A. pentacamerata erevanensis, A. planodorsalis, A. praecursoria, A. primitiva, A. proxima, A. pseudosubsphaerica, A. pseudotopilensis, A. punctocarinata, A. quadratoseptata, A. rotundimarginata, A. rugosoaculeata, A. subintermedia, A. subpentacamerata, A. tadjikistanensis djanaensis, A. triplex, A. umbilicata, A. vedica

Acarinina pseudosubsphaerica

Citation: Acarinina pseudosubsphaerica Pearson & Berggren, in Berggren et al. 2006
Rank: Species
Type locality: Arabian Sea
Type sample (& lithostrat): DSDP Site 220/16/2, 68-70 cm,
Type specimens: PLATE 9.2, FIGURES 9-16 (Pl. 9.2, Figs. 9-10, 14-15: SEMs of holotype and paratypes); Holotype (USNM 523427) and paratypes (USNM 523427a, b, c)
Type repository: Washington; USNM

Current identification/main database link: Acarinina pseudosubsphaerica Pearson & Berggren 2006

Original Description
Wall type: Weakly muricate, cancellate on spiral side with large, bladed muricae on umbilical side, normal perforate, nonspinose.

Test morphology: Compact subspherical test coiled in a high trochospire of about two whorls with circular, slightly lobate outline; 4-6 moderately inflated, radially compressed chambers in final whorl; dorsal sutures wide and depressed, between circular chambers; primary aperture slit-like or a low, broad arch, situated in a wide, open umbilicus, and often covered by a small, sparsely muricate final chamber.

Size: Maximum diameter of holotype 0.19 mm, thickness 0.16 mm

Extra details from original publication
Taxonomic discussion: Despite being a relatively common form in the lower and middle Eocene, Acarinina pseudosubsphaerica n. sp. has not been formally recorded. Acarinina alticonica Fleisher is closely related and the two species have been observed to intergrade in Zone E6/E7 (undifferentiated) of Tanzania Drilling Project Site 2 (P.N. Pearson, unpublished data). Lu and Keller (1995) recorded a first occurrence in Zone P9 (=E7) of Acarinina aquiensis in DSDP Site 577 (Shatsky Rise, north-west Pacific Ocean), which is regarded as conspecific here, and not referable to Loeblich and Tappan’s species (which is a Paleocene form from the Aquia Formation of Virginia and Maryland probably related to/conspecific with Acarinina subsphaerica; see Berggren and Norris, 1997).

Diagnostic characters:
Acarinina pseudosubsphaerica n. sp. is distinguished from all other middle Eocene acarininids by its high spire, small size and subspherical shape. It is similar in morphology to the Paleocene species, A. subsphaerica (Subbotina), but differs from that form and A. alticonica Fleisher by having less closely appressed chambers and a broader umbilicus.

Geographic distribution: Probably widely distributed in tropical and mid-latitude sites.

Isotope paleobiology: Recorded (under the name Muricoglobigerina esnehensis) as a mixed layer dwelling species by Pearson and others, (1993).

Phylogenetic relations: Descended from A. alticonica.

Geological Range: Zone E7 to Zone E10


Berggren, W. A. & Norris, R. D. (1997). Biostratigraphy, phylogeny and systematics of Paleocene trochospiral planktonic foraminifera. Micropaleontology. 43(supplement 1): 1-116. gs

Berggren, W. A., Pearson, P. N., Huber, B. T. & Wade, B. S. (2006b). Taxonomy, biostratigraphy, and phylogeny of Eocene Acarinina. 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(Chap 9): 257-326. gs V O

Lu, G. & Keller, G. (1995). Planktic foraminiferal faunal turnovers in the subtropical Pacific during the Late Paleocene to Early Eocene. Journal of Foraminiferal Research. 25: 97-116. gs

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. gs

Pearson, P. N. et al. (2004). Paleogene and Cretaceous sediment cores from the Kilwa and Lindi areas of coastal Tanzania: Tanzania Drilling Project Sites 1–5. Journal of African Earth Sciences. 39: 25-62. gs


Acarinina pseudosubsphaerica compiled by the pforams@mikrotax project team viewed: 18-4-2021

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