Nannotax3 - ntax_main - Fasciculithaceae

Citation: Fasciculithaceae Hay & Mohler, 1967

Taxonomic discussion: The species traditionally included in Fasciculithus have recently been subdivided into three genera - Fasciculithus, Gomphiolithus and Lithoptychius - and an additional genus, Diantholitha, described (Aubry et al. 2011). This scheme is further described in Aubry et al. (2012) and Monechi et al. (2012). Finally Monechi et al. (2013) provides data on their stratigraphic ranges.
The term "fasciculith" is used here for nannoliths from any of the genera.

Distinguishing features:
Parent taxon (Discoasterales): Radially symmetrical nannoliths formed from one to several separate cycles of elements that radiate from a common centre or axis.
This taxon: Conical or cylindrical discoasteralids consisting of 10-30 wedge-shaped, radially-arranged elements, in one to three superposed cycles.

Typically fasciculiths have a concave end, which is assumed to be proximal, and a convex or pointed end, which is considered distal. The outer surface is often covered by depressions (fenestrae). Typically seen in diagnostic side view.
Key references - Romein 1979; Perch-Nielsen 1985; Aubry et al. 2011; Aubry et al. 2012; Monechi et al. 2012; Monechi et al. 2013; Minatti et al. 2021

Fasciculiths are predominantly moderate size nannliths within the size range 5-9µm and size does not vary much between species. The prime exception is F. tonii which is much bigger, 10-20 µm.

Geological Range:
Last occurrence (top): at top of NP10 zone (100% up, 54.2Ma, in Ypresian 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

References:

Aubry, M. P., Bord, D. & Rodriguez, O. (2011). New taxa of the Order Discoasterales Hay 1977. Micropaleontology. 57(3): 269-287. gs

Aubry, M. -P., Rodriguez, O., Bord, D., Godfrey, L., Schmitz, B. & Knox, R. W. O. B. (2012). The first radation of the Fasciculiths: Morphologic adaptations of the coccolithophores to oligotrophy. Australian Journal of Earth Sciences. 105(1): 29-38. gs

Hay, W. W. & Mohler, H. P. (1967). Calcareous nannoplankton from Early Tertiary rocks at Point Labau, France and Paleocene-Early Eocene correlations. Journal of Paleontology. 41(6): 1505-1541. gs

Miniati, F., Cappelli, C. & Monechi, S. (2021). Revised taxonomy and early evolution of fasciculiths at the Danian–Selandian transition. Journal of Micropalaeontology. 40: 101-144. gs O

Monechi, S., Reale, V., Bernaola, G. & Balestra, B. (2012). Taxonomic review of early Paleocene fasciculiths. Micropaleontology. 58(4): 351-365. gs

Monechi, S., Reale, V., Bernaola, G. & Balestra, B. (2013). The Danian/Selandian boundary at Site 1262 (South Atlantic) and in the Tethyan region: Biomagnetostratigraphy, evolutionary trends in fasciculiths and environmental effects of the Latest Danian Event. Marine Micropaleontology. 98(1): 28-40. gs

Perch-Nielsen, K. (1985). Cenozoic calcareous nannofossils. In, Bolli, H. M., Saunders, J. B. & Perch-Nielsen, K. (eds) Plankton Stratigraphy. Cambridge University Press, Cambridge (1): 427-555. gs

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

Daughter taxa (time control age-window is: 0-800Ma)		Granddaughter taxa
	Diantholitha Squat fasciculiths divided into sub-equal upper and lower cycles with different optical orientations. Conical openings on both sides, no fenestrae	Diantholitha mariposa Diantholitha sp.
	Fasciculithus Conical or cylindrical fasciculiths formed of a single cycle of elements, outer surface is usually covered by fenestrae.	F. alanii group F. involutus group F. schaubii group Fasciculithus sp.
	Gomphiolithus Fasciculiths formed of a single cycle, arguably with central body, deep cavity on the distal side, no fenestrae	Gomphiolithus magnicordis Gomphiolithus magnus
	Lithoptychius Complex fasciculiths - formed of three discrete cycles; no fenestrae	Lithoptychius ulii Lithoptychius chowii Lithoptychius galeottii Lithoptychius maioranoae Lithoptychius varolii Lithoptychius felis Lithoptychius collaris Lithoptychius schmitzii Lithoptychius sp.
	Tectulithus Complex fasciculiths - formed of two discrete cycles; no fenestrae	Tectulithus merloti Tectulithus janii Tectulithus stonehengei Tectulithus pileatus Tectulithus pagodiformis Tectulithus stegastos Tectulithus sp.

Fasciculithaceae

References:

Add Comment

Comments