Nannotax3 - ntax_mesozoic - Stephanolithiaceae

Stephanolithiaceae


Classification: ntax_mesozoic -> Stephanolithiales -> Stephanolithiaceae
Sister taxa: Parhabdolithaceae, Stephanolithiaceae

Distinguishing features:
Parent taxon (Stephanolithiales): Murolith coccoliths with a distal/outer cycle of non-imbricating elements, i.e., in side view, the sutures are vertical or near-vertical.
This taxon: Murolith (protolith type) coccoliths with rims of non-imbricate V-units and weakly-developed, or vestigial, proximal/inner-cycles (R-units), with central-areas spanned by one to numerous bars. 


Daughter taxa (time control age-window is: 0-800Ma)Granddaughter taxa
Cylindralithus
Circular or sub-circular with high, sculpted, wall; central-area vacant or with cross bars.
C. biarcus
C. coronatus
C. sculptus
C. serratus
C. duplex
C. oweinae
C. flat-top
C. nieliae
C. sp.

Darwinilithus
Cylindrical nannofossil with median flange, a flaring cone on one side and a circlet of flaring spines on the other
D. pentarhethum
D. sp.

Rotelapillus
Subcircular to circular; rim high, narrow, bicyclic; central area spanned by radial bars; Short spines protrude from the rim
R. pleoseptatus
R. crenulatus
R. munitus
R. radians
R. hexaradiatus
R. applegatei
R. msakyae
R. sp.

Stephanolithion
Elliptical and often polygonal; rims low but broad, bicyclic; central-area spanned by one to eight bars; prominent spines protrude from the rim
S. atmetos
S. bigotii
S. brevispinus
S. hexum
S. speciosum
S. sp.

Stoverius
Narrowly elliptical to circular; rim low, bicyclic; central area wide, spanned by cross bars.
S. achylosus
S. acutus
S. coangustatus
S. protosignum
S. sp.

Stradnerlithus
Elliptical to diamond-shaped; rims low, narrow, unicyclic; central-area spanned by bars, radiating from central node or a longitudinal bar, usually spine bearing; typically small fragile and inconspicuous in LM.

Polygonal
Corollithion
Polygonal, usually hexagonal; rim bicyclic; central area with 4-6 radial bars
C. completum
C. exiguum
C. karegae
C. kennedyi
C. signum
C. covingtonii
C. madagaskarensis
C. perch-nielseniae
C. sp.

Rhombolithion
Diamond-shaped; rim unicyclic (stradnerlithids).
R. minutum
R. scutulatus
R. rhombicum
R. octocostatum
R. horrellii
R. rotatum
R. duodecostatum
R. sp.

Truncatoscaphus
Polygonal (subhexagonal), often elongate and narrow; muroliths with central area spanned by a longitudinal bar and 6 or more lateral bars.
T. hexaporus
T. octoporus
T. pauciramosus
T. intermedius
T. delftensis
T. macmillanii
T. sp.

Complex central structure
Paralithella
Very small (<2 µm) elliptical stephanolithid; central area with bridge supporting a hollow spine and bars parallel to the long axis
P. recta

Rectocorona
Elliptical murolith with non-imbricate wall and low spine supported by complex central structure
R. brachyrhabda
R. sp.

Thurmannolithion
Elliptical; rim narrow; central area with axial cross, numerous lateral bars and spine
T. clatratum
T. sp.

Taxonomy:

Citation: Stephanolithiaceae Black 1968
Rank: Family

Taxonomic discussion:
The family as originally described by Black (1968) included only Stephanolithion. The concept of the family was broadened by Black (1973). 

Farinacci & Howe catalog pages: Stephanolithiaceae [no catalog entry yet]

Distinguishing features:
Parent taxon (Stephanolithiales): Murolith coccoliths with a distal/outer cycle of non-imbricating elements, i.e., in side view, the sutures are vertical or near-vertical.
This taxon: Murolith (protolith type) coccoliths with rims of non-imbricate V-units and weakly-developed, or vestigial, proximal/inner-cycles (R-units), with central-areas spanned by one to numerous bars. 


Morphology: LM image is usually unicyclic and inconspicuous, although a number of genera do exhibit bicyclicity, e.g. Rotelapillus, Stephanolithion and Stoverius. Coccolith outlines may be polygonal.

Search data:
TagsLITHS: murolith, ca_disjunct,
MetricsLith size: 0->0µm;
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): at top of Maastrichtian Stage (100% up, 66Ma, in Danian stage). Data source: Total of range of species in this database
First occurrence (base): in lower part of Pliensbachian Stage (21% up, 189.1Ma, in Pliensbachian stage). Data source: Total of range of species in this database

Plot of occurrence data:

References:

Black, M. (1968). Taxonomic problems in the study of coccoliths. Palaeontology. 11: 793-813. gs V O

Black, M. (1973). British Lower Cretaceous Coccoliths. I-Gault Clay (Part 2). Palaeontographical Society Monograph. 127: 49-112. gs

Bown, P. R. & Cooper, M. K. E. (1998). Jurassic. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 34-85. gs

Bown, P. R., Rutledge, D. C., Crux, J. A. & Gallagher, L. T. (1998). Early Cretaceous. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series. 86-131. gs


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Stephanolithiaceae compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 24-10-2021

Taxon Search:
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Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=11144 Go to Archive.is to create a permanent copy of this page - citation notes



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