menardii lineage


Classification: pf_cenozoic -> Globorotaliidae -> Globorotalia -> menardii lineage
Sister taxa: hirsuta lineage, menardii lineage, truncatulinoides lineage, tumida lineage, temperate Globorotalia species, G. sp.,
Daughter taxa: - species arranged by lineage and FAD (blue => in age window 0-800Ma)
exilis sublineage
Like G. exilis but larger and with a distinctly more lobate and compressed test.
Like G. limbata but with a more compressed, thinner, and delicate test.
miocenica sublineage
Like G. limbata but with more chambers in final whorl (usually 8-10 vs 6-8), a circular-outline to the test, and a wide, circular and deep umbilicus
Distinguished from other species of the menardii lineage by its distinctly planoconvex test and circular outline.
strongly-biconvex test with a sub-circular equatorial periphery and pronounced keel.
Like G. menardii but uniformly increasing chambers in the final whorl; spiral sutures, initially straight then become sharply curved near the periphery, giving a hockey-stick shape
menardi sublineage
Like G. praemenardii but larger, with raised spiral sutures, and a more massive keel.
Like G. archeomenardii but larger, more lobulate, and with less convex spiral side.
Lenticular, low trochospiral, prominent keel and densely perforate surface; aperture low-arched slit, with a distinct lip

Taxonomy

Citation: menardii lineage
Rank: lineage
Type species: Pulvinulina menardii (Parker, Jones; and Brady, 1865)
Synonyms:
Taxonomic discussion: The subgenus Menardella proposed by Bandy (1972) for the Globorotalia praescitula-archeomenardii-praemenardii-menardii evolutionary lineage, which has been, and remains, an important element of Late Neogene planktonic foraminiferal assemblages of tropical to warm-subtropical waters. Species of the Menardella lineage are characterized by lenticular, trochospiral tests, a prominent keel and smooth, densely perforate surfaces (Pl. 28, Figs. 1, The subgenus Globorotalia, which includes the Gr. lenguaensis-Gr. plesiotumida-Gr. tumida lineage, has many characteristics in common with Menardella, but they are phylogenetically unrelated.

Although Globorotalia (G.) praescitula, originally evolved in the temperate areas, it subsequently migrated to the tropics and thence gave rise to Menardella during the late Early Miocene (Text Fig. 14). Although the earliest representative of Menardella (Gr. (M.) archeomenardii) first appeared within Early Miocene Zone N8, the lineage did not become dominant among the tropical globorotaliids until the extinction of Fohsella at 12.4 Ma.

Members of Menardella during the Pliocene and Quaternary exhibit a wide range of variation, especially with respect to the strength of the keel, the number of chambers in the final whorl coiling mode, and bending of the final chamber.  [Kennett & Srinivasan 1983]

Catalog entries: Globorotalia (Menardella),

Distinguishing features: G. archeomenardii - menardii, limbata - miocenica & exilis - pertenius lineages

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.

Description

Biogeography and Palaeobiology


Geographic distribution: Since Menardella is so distinctly tropical, changes in its relative abundances in stratigraphic sequences have been used extensively as a paleoclimatic tool. [Kennett & Srinivasan 1983]

Most likely ancestor: hirsuta lineage - at confidence level 4 (out of 5). Data source: Kennett & Srinvasan 1983; Stewart 2003; Aze et al. 2011.
Likely descendants: tumida lineage;

Biostratigraphic distribution

Geological Range:
Last occurrence (top): Extant Data source: Total of range of species in this database
First occurrence (base): near top of Burdigalian Stage (94% up, 16.2Ma, 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. 120

References:

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


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menardii lineage compiled by the pforams@mikrotax project team viewed: 21-7-2019

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Short stable page link: http://mikrotax.org/pforams/index.php?id=104168 Go to Archive.is to create a permanent copy of this page - citation notes



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