CATALOG OF ORIGINAL DESCRIPTIONS: Planoheterohelix praenuttalli Haynes, Huber & MacLeod 2015

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 -> P -> Planoheterohelix -> Planoheterohelix praenuttalli
Other pages this level: P. postmoremani, P. praenuttalli,

Planoheterohelix praenuttalli

Citation: Planoheterohelix praenuttalli Haynes, Huber & MacLeod 2015
Rank: Species
Type locality: Tanzania Drilling Project Site 31, southeastern coastal region of Tanzania, Africa. Geographic coordinates: 10 degerees 1minute 49.8 seconds S/39 degrees 38minutes 44.0 seconds E.
Type age: Middle Turonian (Marginotruncana schneegansi
Holotype Repository: Washington; USNM
Type & figured specimens: 560331

Linked specimens: USNM-560332 USNM-606424 USNM-560333 USNM-606426 USNM-606428 USNM-606425 USNM-606427 USNM-560331

Current identification/main database link: Planoheterohelix praenuttallii Haynes, Huber & MacLeod 2015

Original Description
Test relatively large (typically greater than 300 microns in length, average is 304 microns, n = 11), broadly rounded, consists of 9 to 12 chambers (n = 12) that are biserially arranged and globular throughout. The diameter of the proloculus is variable (range = 15 to 32 microns, n = 7) and subsequent chambers rapidly increase in size, resulting in a strongly tapered, subtriangular outline in side and edge views. Sutures are straight, strongly depressed, and generally meet the central axis at a right angle. Aperture is a symmetrical semicircular, low, broad arch at the base of the final chamber, bordered by an imperforate lip. Periapertural flanges are absent. Test wall is calcitic and hyaline. Chamber surface is finely perforate to macroperforate (pore diameter = 0.9 to 3.2 microns, n = 2) and is ornamented with costae that vary from almost completely smooth to those with discontinuous costae that are up to 4.3-microns thick. Distinguishing features. Planoheterohelix praenuttalli is generally large, strongly tapering, and almost as broad (in edge view) as it is wide (in side view).

Editors' Notes
Described as Planoheterohelix praenuttalli the name has since been corrected to Planoheterohelix praenuttallii 


Haynes, S., Huber, B. T. & MacLeod, K. G. (2015). Evolution and phylogeny of mid-Cretaceous (Albian-Coniacian) biserial planktic foraminifera. Journal of Foraminiferal Research. 44: 42-81. gs :: ::


Planoheterohelix praenuttalli compiled by the pforams@mikrotax project team viewed: 6-7-2020

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