Nannotax3 - ntax_cenozoic - Sphenolithus Nannotax3 - ntax_cenozoic - Sphenolithus

Sphenolithus


Classification: ntax_cenozoic -> Discoasterales -> Sphenolithaceae -> Sphenolithus
Sister taxa: Sphenolithus, Furcatolithus

moriformis group ranges from Paleocene to Pliocene, the other groups are arranged in age sequence (time control age-window is: 0-800Ma)Granddaughter taxa
S. moriformis group
Conical and hemispherical sphenoliths without prominent apical spines.
Sphenolithus abies
Sphenolithus apoxis
Sphenolithus moriformis
Sphenolithus grandis
Sphenolithus puniceus
Sphenolithus acervus
Sphenolithus primus

Oligocene-Miocene groups
S. heteromorphus group
Late Oligocene - Early Miocene sphenoliths with apical spines formed from a single element.
Sphenolithus heteromorphus
Sphenolithus milanetti
Sphenolithus preasii
Sphenolithus pseudoheteromorphus
Sphenolithus conicus
Sphenolithus calyculus

S. delphix group

Sphenolithus belemnos
Sphenolithus tintinnabulum
Sphenolithus bipedis
Sphenolithus delphix
Sphenolithus microdelphix
Sphenolithus spinula

S. capricornutus group
Apical spine formed of radiating elements
Sphenolithus capricornutus
Sphenolithus cometa
Sphenolithus multispinatus

S. dissimilis group
Bases cylindrical or conical, compound apical spine
Sphenolithus disbelemnos
Sphenolithus dissimilis
Sphenolithus procerus
Sphenolithus compactus
Sphenolithus truaxii

Eocene - Oligocene groups
S. furcatolithoides group
Small Middle Eocene sphenoliths with duocrystaline spines that are dark in the 45° position.
Sphenolithus recolletensis
Sphenolithus strigosus
Sphenolithus furcatolithoides
Sphenolithus pseudofurcatolithoides
Sphenolithus perpendicularis
Sphenolithus kempii

S. radians group
Eocene to Early Oligocene sphenoliths with compound spines, that are visible but dim at 0° and brightest when at 45° to the polarizing directions.
Sphenolithus pseudoradians
Sphenolithus radians
Sphenolithus arthurii
Sphenolithus richteri
Sphenolithus spiniger
Sphenolithus orphanknollensis
Sphenolithus editus

S. anarrhopus group
Late Paleocene and Early Eocene sphenoliths with monocrystalline spines
Sphenolithus anarrhopus
Sphenolithus conspicuus
Sphenolithus villae

Sphenolithus sp.
Specimens which cannot be assigned to established species

Taxonomy:

Citation: Sphenolithus Deflandre in Grassé, 1952
taxonomic rank: Genus
Type species: Sphenolithus radians Deflandre in Grassé, 1952
Synonyms:
Taxonomic discussion: More than 40 species of Sphenolithus have been described. We subdivide them here into informal groups which we believe represent clusters of closely related species, or in some cases single morphologically variable species. The primary criteria are the nature of the spine which may be barely developed (moriformis group), formed of numerous elements (radians group), two elements (predistentus and furcatolithoides groups), or a single element (conspicuus and heteromorphus groups). In addition the base may be formed of several cycles of elements (most groups) or only one cycle (predistentus group).
There has been a tendency toward recognition of ever more sphenolith "species", but it is by no means clear that these reflect biological species, as discussed by Towe (1979). 
See also - Perch-Nielsen 1985; Aubry 1989; Maiorano & Monechi 1997; Shamrock 201; Bergen et al. 2017; Howe 2021

Distinguishing features:
Parent taxon (Sphenolithaceae): Conical discoasteralids with a concave base, consisting of a mass of elements radiating from a common origin.
This taxon: Conical nannoliths with a concave base, consisting of a mass of elements radiating from a common origin.

Farinacci & Howe catalog pages: Sphenolithus + * , Sphenaster * , Nannoturbella *


Morphology:

see family

Search data:
LITHS: nannolith-radiate, circular, cylindrical, CROSS-POLARS: R-prominent,
Lith size: 4->20µm;
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 NN16 zone (100% up, 2.5Ma, in Gelasian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within NP4 zone (61.51-63.25Ma, base in Danian stage). Data source: Total of ranges of species in this database

Plot of occurrence data:

References:

Aubry, M. -P. (1989a). Handbook of Cenozoic calcareous nannoplankton. Book 3: Ortholithae (Pentaliths, and others), Heliotithae (Fasciculiths, Sphenoliths and others). Micropaleontology Press, American Museum of Natural History, New York. 1-279. gs

Bergen, J. A., de Kaenel, E., Blair, S. A., Boesiger, T. M. & Browning, E. (2017). Oligocene-Pliocene taxonomy and stratigraphy of the genus Sphenolithus in the circum North Atlantic Basin: Gulf of Mexico and ODP Leg 154. Journal of Nannoplankton Research. 37(2-3): 77-112. gs O

Bown, P. R. & Dunkley Jones, T. (2012). Calcareous nannofossils from the Paleogene equatorial Pacific (IODP Expedition 320 Sites U1331-1334). Journal of Nannoplankton Research. 32(2): 3-51. gs O

Deflandre, G. (1952). Classe des Coccolithophoridés. (Coccolithophoridae. Lohmann, 1902). In, Grassé, P. P. (ed.) Traité de Zoologie. Masson, Paris 439-470. gs

Howe, R. (2021). Ultrastructure and taxonomy of the family Sphenolithaceae. Journal of Nannoplankton Research. 39(1): 29-75. gs O

Maiorano, P. & Monechi, S. (1997). New Early Miocene species of Sphenolithus Deflandre, 1952 from the North Atlantic Ocean. Journal of Nannoplankton Research. 19(2): 103-107. gs

Martini, E. (1965). Mid-Tertiary calcareous nannoplankton from Pacific deep-sea cores. Colston Papers. 17: 393-411. gs O

Perch-Nielsen, K. (1985). Cenozoic calcareous nannofossils. In, Bolli, H. M., Saunders, J. B. & Perch-Nielsen, K. (eds) Plankton Stratigraphy. Cambridge University Press, Cambridge 427-555. gs

Romein, A. J. T. (1979). Lineages in Early Paleogene calcareous nannoplankton. Utrecht Micropaleontological Bulletin. 22: 1-231. gs O

Towe, K. M. (1979). Variation and systematics in calcareous nannofossils of the genus Sphenolithus. American Zoologist. 19: 555-572. gs

Wilcoxon, J. A. (1970). Sphenaster new genus, a Pliocene calcareous nannofossil from the tropical Indo-Pacific. Tulane Studies in Geology and Paleontology. 8: 78-81. gs


nannotaxlogo400px

Sphenolithus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 26-5-2024

Taxon Search:
Advanced Search

Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=1277 Go to Archive.is to create a permanent copy of this page - citation notes
nannotaxlogo400px

Nannotax is being sponsored through 2024 by Woodside Energy and Shell USA


Add Comment

* Required information
Captcha Image
Powered by Commentics

Comments (4)

Avatar
David Campbell(US)

The reported Gelasian occurrence seems to be based on the PDBD record at https://paleobiodb.org/classic/basicCollectionSearch?collection_no=152368&is_real_user=1. However, the actual ODP record clearly states the actual age for the Sphenolithus specimens. As this PDBD entry also identifies Emiliania huxleyi as a bivalve and wrongly reports it from the Gelasian as well, the PDBD needs editing.

Avatar
Jeremy Young

Hi

Thanks for the comment - the posting was delayed because comments with links need to be approved (otherwise we get flooded with spam). We don't use PBDB at all - there is not much useful nannofossil data on it. The range into the Gelasian for Sphenolithus is in fact a rounding problem - S. abies gets into NN16 and NN16 extends into the Gelasian. So, I should emend the code which summarises ranges for higher taxa. In most cases rounding to stage level makes sense but occasionally, as here, it produces unfortunate errors.

Jeremy

Avatar
Kenneth M. Towe(US)
This old paper should be added to the list of references...

1979 K.M. Towe, Variation and systematics in calcareous nannofossils of the genus Sphenolithus. AMERICAN ZOOLOGIST, v. 19, p. 555-572.

It should give pause to the discussion of various "species" in this genus.
Avatar
Jeremy Young(UK)
good point - do you have a pdf copy of the paper. it would be nice to include your reconstruction of sphenolithus sphere.