hirsuta lineage

Classification: pf_cenozoic -> Globorotaliidae -> Globorotalia -> hirsuta lineage
Sister taxa: hirsuta lineage, menardii lineage, truncatulinoides lineage, tumida lineage, temperate Globorotalia species, G. sp.,
Daughter taxa: (blue => in age window 0-800Ma) Granddaughter taxa
margaritae->hirsuta sublineage
Distinguished by its thick, relatively high-spired test, 4 chambers in the final whorl, and pustulose surface.

Distinct but thin peripheral keel and strongly recurved spiral sutures, lobate outline

Like G. juanai & scitula, but more convexly rounded spiral side and concave to flat umbilical side; more delicate peripheral keel, and in the distinctly elongate, narrower, and more strongly curved chambers on spiral side.

Like G. scitula but periphery rounded and early chambers umbonate

scitula sublineage
Like G. scitula but much smaller, has inflated chambers on the umbilical side, and a more irregularly perforated test.

Like G. praescitula but smooth surface and subcircular outline

Like G. zealandica but more chambers in final whorl (4½ vs 4), increased curvature of the sutures on the umbilical side, peripheral compression, and a return to a low-arched aperture

other species
Distinguished by its biconvex test with a rounded periphery (sometimes angular or narrowly keeled in the final chamber.)

Like G. scitula but much larger (>0.5mm vs ca 0.3mm)

Like G. praescitula, but 5-5½ chambers in final whorl (vs 4½), more inflated chambers, and a more rounded periphery


Citation: hirsuta lineage Bandy 1972
Rank: lineage
Type species: Rotalina hirsuta d'Orbigny, 1839
Taxonomic discussion: Bandy (1972) proposed the subgenus Hirsutella for the Globorotalia scitula-Gr. margaritae-Gr. hirsuta lineage. Hirsutella includes sharp-edged to keeled forms and inflated to compressed forms. Most of the species are thin walled, with smooth and densely perforate tests (PI. 31, Figs. 1,2). Elements of the Hirsutella lineage differ from Menardella in being of smaller size and in possessing a tight, quadrate coil and long crescentic-shaped chambers on the spiral side.

Globorotalia (Globoconella) praescitula is the ancestral form for the Hirsutella lineage. During the early Middle Miocene, Gr. (G.) praescitula evolved into Globorotalia (Hirsutella) scitula in tropical to temperate areas and Globorotalia (Hirsutella) challengeri in temperate areas. Later in the Middle to Late Miocene, several taxa evolved in turn from Globorotalia (Hirsutella) scitula (Text Fig. 15). [Kennett & Srinivasan 1983]

There are significant inconsistencies in the literature regarding the hirsuta lineage. In particular:
  1. Stainforth (1975) and Kennett & Srinivasan (1983) regard G. juanai as the senior synonym of G. praemargaritae and part of the challengeri->margaritae lineage. By contrast Stewart (2003) and Aze etal. (2011) regard praemargaritae and juanai as separate species and sugest that juanai evolved from challengeri. The more tradtional interpretation is followed here.
  2. G. hirsuta is often indicated as evolving from directly from G. margaritae  - e.g. Kennett & Srinivasan (1983), Aze et al. (2011). However, according to Wade et al. (2011) there is a 3.5Ma range gap between these two species. 

Catalog entries: Globorotalia (Hirsutella), Obandyella

Distinguishing features: G. scitula - juanai - margaritae - hirsuta lineage

NB These concise distinguishing features statements are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus.
They are being edited as the site is developed and comments on them are especially welcome.


Biogeography and Palaeobiology

Biostratigraphic distribution

Geological Range:
Last occurrence (top): Extant Data source: Total of range of species in this database
First occurrence (base): in mid part of Burdigalian Stage (48% up, 18.3Ma, in Burdigalian stage). Data source: Total of range of species in this database

Plot of occurrence data:

Primary source for this page: Kennett & Srinivasan 1983, p. 132


Bandy, O. L. (1972). Origin and development of Globorotalia (Turborotalia) pachyderma (Ehrenberg). Micropaleontology. 18(3): 294-318. gs

Haman, D., Huddleston, R. W. & Donahue, J. P. (1981). Obandyella, a new name for Hirsutella Bandy, 1972 (Foraminiferida) non Cooper and Muir Wood,1951 (Brachiopoda). Proceedings of the Biological Society of Washington. 93(4): 1264-1265. gs

Kennett, J. P. & Srinivasan, M. S. (1983). Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania. 1-265. gs


hirsuta lineage compiled by the pforams@mikrotax project team viewed: 22-1-2020

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Short stable page link: http://mikrotax.org/pforams/index.php?id=104167 Go to Archive.is to create a permanent copy of this page - citation notes

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