pforams@mikrotax - Morozovella formosa

Citation: Morozovella formosa (Bolli 1957)

Basionym: Globorotalia formosa formosa

Synonyms:

?Globorotalia velascoensis (Cushman)._Cushman and Renz, 1946:47, pl. 8: figs. 13-14 [upper Lizard Springs Fm., Trinidad; see Renz, 1951 for corrected figure explanation]. [Not Cushman, 1925.]
Globorotalia formosa formosa Bolli 1957b:76, pl. 18: figs. 1-3 [lower Eocene G. formosa formosa Zone, upper Lizard Springs Fm., Trinidad].—Luterbacher, 1964:694-696, text-figs. 118a-c [G. formosa formosa Zone, upper Lizard Springs Fm., Trinidad]; 119a-c [G. formosa formosa /G. subbotinae Zone, Gubbio section, Central Apennines, Italy]; 120a-122c [G. aragonensis Zone, Gubbio section, Italy]. —Samanta, 1970:624, pl. 97: figs. 15, 16 [upper Marlstone of Pondicherry Fm., southeastern India].— Stainforth and others, 1975:184, text-fig. 48.1-5 [G. formosa formosa Zone, Lodo Fm., California]; 48.6 [reillustration of holotype from Bolli, 1957b, pl. 18, figs. 1-3].—Luterbacher, 1975b:65, pl. 5: figs. 16-18 [G. formosa formosa Zone, Possagno section, Italy].— Toumarkine and Luterbacher, 1985:112, Fig. 15.13 [holotype reillustrated].
Pseuodogloborotalia formosa (Bolli).—Bermúdez, 1961:1343, 1344.
Globorotalia formosa Bolli. —Postuma, 1971:190, figures on p. 191 [lower Eocene, Cuba].
Morozovella formosa (Bolli).—Berggren, 1971, pl. 5: figs. 15, 16 [Zone P6b, DSDP Hole 20C, South Atlantic Ocean].
Globorotalia (Morozovella) formosa Bolli.—Blow, 1979:1000, pl. 127: figs. 3 and 4 [Zone P8a, DSDP Hole 47.2, Shatsky Rise, northwest Pacific Ocean]; pl. 134: figs. 7, 8, pl. 224: fig. 4 [Zone P8b, DSDP Hole 47.2, Shatsky Rise, northwest Pacific Ocean]; pl. 138: figs. 9, 10; pl. 224: fig. 3 [Zone P8b, DSDP Hole 20C, South Atlantic Ocean].
Morozovella formosa formosa (Bolli).—Warraich and others, 2000:293, fig. 17. 21-23 [Zone P7, Dungan Fm., Rakhi Nala section, Sulaiman Range, Pakistan].—Warraich and Ogasawara, 2001, 39, figs. 9. 13-15 [Zone P7, Dungan Fm., Rakhi Nala section, Sulaiman Range, Pakistan].

Taxonomic discussion: Blow (1979, p. 1000, 1001) drew attention to the fact that formosa and the crater -caucasica complex, while seemingly morphologically distinct when treated as isolated individuals, in fact require close scrutiny in order to retain the biostratigraphic utility of both. He further pointed out the gross homeomorphy between formosa and some morphotypes of the older velascoensis. Finally he observed that some of the phylogenetically advanced morphotypes of the velascoensis and the lensiformis-crater -caucasica “gens” exhibit features in common with formosa; a sort of “threefold homeomorphy” as he dubbed it. Distinction among the different morphotypes was made on the following basis:
1. formosa is flat to slightly convex in dorsal (spiral) aspect with chambers somewhat longer (anterio-posteriorly) tangentially than broad radially.
2. formosa has dorsal /spiral intercameral sutures nearly radial proximally but recurved (but not sharply retorse) near periphery.
3. velascoensis has chambers in dorsal/spiral aspect nearly equidimensional and spiral intercameral sutures exhibit retorse distal part.
4. In axial-apertural view anguloconical angle in formosa is markedly acute (~ 45o), whereas in velascoensis it is nearly a right-angle (~ 80-85o); the umbilico-peripheral part of chamber is often somewhat concave in the area between the peripheral test
muricocarina and the “horn-like”, adumbilically pointed umbilical shoulders.
5. Whereas the anguloconical angle in the crater -caucasica group is comparable to that in formosa, the earlier chambers have a more rounded appearance in axial/edge view.
6. The umbilicus in formosa is wide and the angle made by the junction of the chamber walls interior and exterior to the umbilicus is on the order of ~ 40-45o; in crater this angle is ~ 60-65o in the case of the earlier chambers and the umbilical shoulders are more gently rounded, only the last 2-3 chambers exhibiting a strongly reflexed angle between interior and exterior chamber walls.
7. The main distinguishing feature separating formosa from the other forms above is the nature of the early vorticiform spiral intercameral sutures together with the acute conical angle and the distinctly flat spiral side. [Berggren & Pearson 2006]

Distinguishing features:
Parent taxon (Morozovella): Test typically plano-convex, chambers strongly anguloconical.
Wall strongly pustulose (muricate) on parts of spire and umbilicus. Most species with muricocarina.
This taxon: Like M. gracilis but test larger and more robust; more chambers in final whorl (6-7, rarely 8) and wider umbilicus.

Description

Test subcircular, moderately lobulate peripheral outline, planoconvex; chambers triangular, inflated and subangular on umbilical side; trapezoidal with curved margins on spiral side; 15-18 chambers arranged in approximately 3 whorls on spiral side and generally 6-6½ chambers (rarely 7-8) in final whorl on umbilical side with muricae scattered on early chambers of last whorl; sutures moderately depressed, weakly curved (early chambers) to straight, radial (later chambers) on last whorl; umbilicus open, moderately wide, deep; primary aperture a low umbilical-extraumbilical arch extending to peripheral margin; gradual increase in chamber size throughout although last 2-3 chambers exhibit varying size; muricate sutures strongly curved, flush with/slightly elevated above test surface; umbilico-convex in edge view; spiral side flat or nearly so; strongly muricate keel. [Berggren & Pearson 2006]

Muricate, nonspinose, normal perforate. [Berggren & Pearson 2006]

Dimensions of holotype: maximum diameter: 0.65 mm. [Berggren & Pearson 2006]

Biogeography and Palaeobiology

Widely distributed in (sub)tropical regions (Caribbean Sea, Atlantic, Pacific, Tethyan, Indian and Austral Oceans). [Berggren & Pearson 2006]
Aze et al. 2011 summary: Low latitudes; based on Berggren & Pearson (2006)

No data available. [Berggren & Pearson 2006]
Aze et al. 2011 ecogroup 1 - Open ocean mixed-layer tropical/subtropical, with symbionts; based on comparison with other species of the genus.

This taxon evolved from M. gracilis and does not appear to have left any descendants. [Berggren & Pearson 2006]

Most likely ancestor: Morozovella gracilis - at confidence level 4 (out of 5). Data source: Berggren & Pearson (2006) f11.1.

Biostratigraphic distribution

Geological Range:
Notes: Base of Zone E4 (by definition) to top of Zone E6 (by definition). [Berggren & Pearson 2006]
The FAD of Morozovella formosa marks the base of zone E4 / top of E3 (Wade et al. 2011)
Last occurrence (top): at top of E6 zone (100% up, 50.2Ma, in Ypresian stage). Data source: Berggren & Pearson (2006) f11.1
First occurrence (base): at base of E4 zone (0% up, 54.6Ma, in Ypresian stage). Data source: zonal marker (Wade et al. 2011)

Primary source for this page: Berggren & Pearson 2006 - Eocene Atlas, chap. 11, p. 365

References:

Berggren, W. A. & Pearson, P. N. (2006a). Taxonomy, biostratigraphy, and phylogeny of Eocene Morozovella. 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 11): 343-376. gs O

Berggren, W. A. (1971c). Paleogene planktonic foraminiferal faunas on Legs I-IV (Atlantic Ocean) JOIDES Deep Sea Drilling Program: a synthesis. In, Farinacci, A. (ed.) Proceedings of the Second Planktonic Conference, Roma 1970. Edizioni Tecnoscienza, Rome 57-77. gs

Bermudez, P. J. (1961). Contribucion al estudio de las Globigerinidea de la region Caribe-Antillana (Paleoceno-Reciente). Editorial Sucre, Caracas. (3): 1119-1393. gs

Blow, W. H. (1979). The Cainozoic Globigerinida: A study of the morphology, taxonomy, evolutionary relationships and stratigraphical distribution of some Globigerinida (mainly Globigerinacea). E. J. Brill, Leiden. 2: 1-1413. gs

Bolli, H. M. (1957d). The genera Globigerina and Globorotalia in the Paleocene-Lower Eocene Lizard Springs Formation of Trinidad. In, Loeblich, A. R. , Jr., Tappan, H., Beckmann, J. P., Bolli, H. M., Montanaro Gallitelli, E. & Troelsen, J. C. (eds) Studies in Foraminifera. U.S. National Museum Bulletin . 215: 61-82. gs

Cushman, J. A. & Renz, H. H. (1946). The foraminiferal fauna of the Lizard Springs formation of Trinidad, British West Indies. Cushman Laboratory for Foraminiferal Research, Special Publication. 18: 1-48. gs

Cushman, J. A. (1925e). Some new foraminifera from the Velasco shale of Mexico. Contributions from the Cushman Laboratory for Foraminiferal Research. 1(1): 18-23. gs

Luterbacher, H. P. (1964). Studies in some Globorotalia from the Paleocene and Lower Eocene of the Central Apennines. Eclogae Geologicae Helvetiae. 57: 631-730. gs O

Luterbacher, H. P. (1975b). Planktonic Foraminifera of the Paleocene and Early Eocene, Possagno Section. Schweizerische Paläontologische Abhandlungen. 97: 57-67. gs

Postuma, J. A. (1971). Manual of planktonic foraminifera. Elsevier for Shell Group, The Hague. 1-406. gs

Stainforth, R. M., Lamb, J. L., Luterbacher, H., Beard, J. H. & Jeffords, R. M. (1975). Cenozoic planktonic foraminiferal zonation and characteristics of index forms. University of Kansas Paleontological Contributions, Articles. 62: 1-425. gs O

Toumarkine, M. & Luterbacher, H. (1985). Paleocene and Eocene planktic foraminifera. In, Bolli, H. M., Saunders, J. B. & Perch-Neilsen, K. (eds) Plankton Stratigraphy. Cambridge Univ. Press, Cambridge 87-154. gs

Wade, B. S., Pearson, P. N., Berggren, W. A. & Pälike, H. (2011). Review and revision of Cenozoic tropical planktonic foraminiferal biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale. Earth-Science Reviews. 104: 111-142. gs

Warraich, M. Y. & Ogasawara, K. (2001). Tethyan Paleocene-Eocene planktic foraminifera from the Rakhi Nala and Zinda Pir land sections of the Sulaiman Range, Pakistan. Science Reports of the Institute of Geosciences, University of Tsukuba. 22: 1-59. gs

test outline:	Subcircular	chamber arrangement:	Trochospiral	edge view:	Planoconvex	aperture:	Umbilical-extraumbilical
sp chamber shape:	Crescentic	coiling axis:	Low	periphery:	Single keel	aperture border:	N/A
umb chbr shape:	Subtriangular	umbilicus:	Wide	periph margin shape:	Subangular	accessory apertures:	None
spiral sutures:	Raised muricate	umb depth:	Deep	wall texture:	Moderately muricate	shell porosity:	Finely Perforate: 1-2.5µm
umbilical or test sutures:	Moderately depressed	final-whorl chambers:	6-6.5	N.B. These characters are used for advanced search. N/A - not applicable

Morozovella formosa

Taxonomy

Description

Biogeography and Palaeobiology

Biostratigraphic distribution

References:

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