TaxonConcept: Morozovella edgari Premoli Silva & Bolli 1973 from: Pearson, P.N.Olsson, R.K.Hemleben, C.Huber, B.T.Berggren, W.A. (2006): Atlas of Eocene Planktonic Foraminifera. p. 1-513

Click on a letter below to get a list of species:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z all

Morozovella edgari Premoli Silva & Bolli 1973 from: Pearson, P.N.Olsson, R.K.Hemleben, C.Huber, B.T.Berggren, W.A. (2006): Atlas of Eocene Planktonic Foraminifera. p. 1-513

Anonymous: Unedited TaxonConcept data

Notice: This catalogue page may contain unedited data.

Species Morozovella edgari Premoli Silva & Bolli 1973

Diagnosis / Definition:

Pearson et al. (2006):
DESCRIPTION. Type of wall: Muricate, nonspinose, normal perforate. Test morphology: Low to moderately conical trochospiral; weakly lobulate peripheral outline, 5-6 gradually enlarging , cuneiform-shaped chambers in last whorl, intercameral sutures on umbilical side radial, straight and weakly incised; on spiral side chambers trapezoidal in shape, separated by distinctly curved sutures which are flush with the test; early part/chambers of the test raised (i.e., the test exhibits an unequal biconvexity); umbilicus narrow, deep; distinct muricocarina extends to final chamber; aperture a low umbilical-extraumbilical arch extending nearly to the periphery; surface distinctly muricate with concentration of pustules decreasing towards terminal chambers. Size: Dimensions of holotype: maximum diameter: 0.2 1 mm.

Discussion / Comments:

Toumarkine & Luterbacher (1985):
This species is characterized by its small size, fragile aspect with only a weakly developed ' keel', and the relatively large number of chambers (4 to 6) in the last whorl. It differs from Morozovella subbotinae by the larger number of chambers in the last whorl and the less lobate peripheral outline. M. formosa gracilis is more robust and has a better-developed 'keel'.
Pearson et al. (2006):
DISTINGUISHING FEATURES.- This taxon is characterized by its relatively small size, narrow and deep umbilicus, and weakly developed peripheral muricocarina. It bears a close resemblance to juvenile individuals of M. velascoensis from which it is believed to have evolved (Kelly and others, 2001). DISCUSSION.- This minute morozovellid (test diameter ranges from 0.2-0.25 mm) is associated with, and ranges beyond, terminal members of the Morozovella velascoensis group. Kelly and others (200 1, p. 507) have suggested that edgari descended from velascoensis by a process called "terminal progenesis" in which the diminutive descendant (edgari) with an adult morphology resembles the juvenile stages of the ancestral form velascoensis. Morozovella finchi Blow is placed in the synonomy of this taxon. It shares most morphologic features in common with edgari except that the holotype is somewhat larger (0.32 mm) in diameter. It was described from Zone P5 (of Blow, 1979) and said to range to Zone P7 (=E4 of this paper), a range comparable to that ascribed to edgari here. Blow (1 979, p. 999-1000) was of the opinion that finchi descended from "Acarinina " trichotrocha and even included a paratype from the Hornerstown Formation (Zone P4) of New Jersey (erroneously ascribed to Zone P5) in his new taxon ,finchi, but our examination of this form at the USNM suggests that this specimen is not ascribable to ,finchi (=edgari). PHYLOGENETIC RELATIONSHIPS.- This taxon evolved from Morozovella velascoensis (by means of a gradual decrease in test size and truncation of the ancestral ontogenetic sequence; Kelly and others, 2001) but does not appear to have left any descendants. STRATIGRAPHIC RANGE.- Zone E2 (uppermost part) to Zone E3. GEOGRAPHIC DISTRIBUTION.- Probably widely distributed in (sub)tropical regions (Caribbean, Atlantic Ocean and Pacific Ocean) but records are sparse owing to this taxon having been overlooked heretofore. We have found this form relatively commonly distributed in lower Eocene strata (Esna Shales) of Egypt. STABLE ISOTOPE PALEOBIOL0GY.- Shallow-intermediate depth-habitat (Kelly and others, 2001).

Systematics:

15
Classis Foraminifera
  Genus Morozovella
   Species Morozovella edgari

35
  Ordo Foraminiferida
   Superfamilia Globigerinaceae
    Familia Truncorotaloididae
     Genus Morozovella
      Species Morozovella edgari

Synonym list:

Toumarkine & Luterbacher (1985):

1973 Globorotalia edgari Premoli Silva & Bolli. - Premoli Silva & Bolli : p.525 pl 7 figs 10-12, pl 8 figs 1-12 (type reference)

1985 Morozovella edgari Premoli Silva & Bolli. - Toumarkine & Luterbacher : p.113 fig 15.6

Pearson et al. (2006):

1973 Globorotalia edgari Premoli Silva & Bolli. - Premoli Silva & Bolli : p.526 pl. 7, fig. 10-12; pl. 8, fig. 1 (holotype)-12 [Globorotalia edgari Zone, DSDP Site 152, Nicaragua Rise, Caribbean Sea]

1979 Globorotalia (Morozovella) finchi Blow. - Blow : p.999 pl. 99; fig. 6-11 (holotype) [Zone P5, DSDP Hole 47.2, Shatsky Rise, Pacific Ocean]

1985 Morozovella edgari Premoli Silva & Bolli. - Toumarkine & Luterbacher : p.114 text-fig. 15.6a (holotype) and 6b, c (paratypes)reillustrated

2001 Morozovella edgari Premoli Silva & Bolli. - Kelly et al. : p.509 text-fig. 1D-F; text-fig. 3C [lower Eocene, ODP Hole 865B, Allison Guyot, Mid-Pacific Mountains, Pacific Ocean]; text-fig. 2E [Zone P6a, DSDP Site 152, Caribbean Sea]

2006 Morozovella edgari Premoli Silva & Bolli. - Pearson et al. : p.356 pl. 11.6; fig. 1-16 (Pl. 11.6, Figs. 1-7: reillustrations of holotype and paratypes of Globorotalia edgari Premoli Silva and Bolli)

Specimen:

National Museum of Natural History, Basel, Inventory number: C-29482
National Museum of Natural History, Basel, Inventory number: C-29483
National Museum of Natural History, Basel, Inventory number: C-29484
National Museum of Natural History, Basel, Inventory number: C-29485
National Museum of Natural History, Basel, Inventory number: C-29486

References:

Premoli Silva,I. and Bolli,H.M. (1973):
Late Cretaceous to Eocene planktonic foraminifera and stratigraphy of Legs 15 sites in the Carribean Sea.
In: Initial Reports of the Deep Sea Drilling Program Vol. 15 p. 449-547

Blow,W.H. (1979):
The Cainozoic Globigerinida. 3 Vols p. 1413 pp

Toumarkine,M. and Luterbacher,H.P. (1985):
Paleocene and Eocene Planktic Foraminifera.
In: Plankton Stratigraphy p. 87-154

Kelly,D.C.; Bralower,T.J. and Zachos,J.C. (2001):
On the demise of the Early Paleogene Morozovella velascoensis lineage: terminal progenesis in the planktonic Foraminifera . Palaios Vol. 16 p. 507-523

Pearson,P.N.; Olsson,R.K.; Hemleben,C.; Huber,B.T. and Berggren,W.A. (2006):
Atlas of Eocene Planktonic Foraminifera. p. 1-513

Anonymous: Unedited TaxonConcept data

This work is licensed under a Creative Commons Attribution 2.5 License.

Taxon Concept provided by
Home \| Search