Distinguishing features:
Parent taxon (Holococcoliths): Coccoliths formed of minute (ca 0.1µm) rhombohedral micro-crystals. Often a life-cycle stage with heterococcolith counterpart(s).
This taxon: Less common genera
Daughter taxa (time control age-window is: 0-800Ma)![]() | Granddaughter taxa | ||||
Disk-shaped holococcoliths | |||||
![]() | ![]() | ![]() | Bifidalithus Holococcoliths formed from two blocks divided by a transverse suture. | ||
![]() | Bilapillus Holococcolith with narrow rim and two blocks in central area | ||||
Multipartis Holococcoliths formed from ~7 triangular blocks with irregular blocks in the central-area. | |||||
![]() | ![]() | ![]() | Munarinus Holococcoliths formed from 4-12 blocks with central-area filled or spanned by disjunct bar or block. | ||
![]() | ![]() | ![]() | Octolithus Holococcolith formed of 8 blocks, typically 4 large and 4 small. | ||
![]() | ![]() | Okkolithus Elliptical holococcolith with broad rim of numerous small blocks and central area of two or more blocks | |||
Ottavianus Elliptical holococcolith with rim of multiple small elements, central are open except for bridge across short axis. | |||||
![]() | Pharus Elliptical coccolith formed of a single block, with two perforations | ||||
Ramsaya Holococcoliths with rim of 12-14 blocks and central-area spanned by a narrow, dark bar. | |||||
![]() | ![]() | ![]() | ![]() | Russellia Holococcoliths with rim of 10-26 blocks and a small central block. | |
![]() | ![]() | Saepiovirgata Holococcoliths with rim formed from 8-12 elements, and 2 longitudinally-oriented elongate blocks in the central-area. | |||
Other forms - mostly cavate | |||||
![]() | ![]() | Acuturris Holococcoliths with a proximal plate of three blocks and tall, tapering spines. | |||
![]() | ![]() | ![]() | Anfractus Elliptical, cavate (and usually septate) holococcoliths, often bearing hollow spines. Distal surfaces may be perforate and there may be internal buttresses. | ||
![]() | ![]() | ![]() | ![]() | Duocameratus Cavate holococcolith with central septum | |
Lacunolithus-Bown | |||||
![]() | Metadoga Cavate, conical-flask shaped holococcolith with lid and internal partition. | ||||
![]() | ![]() | ![]() | Nicholasia Conical shaped holococcolith, usually seen in side view, base weak or absent | ||
![]() | ![]() | ![]() | Paulpearsonia Cavate holococcoliths with thin rims and small spines; whole holococcolith behaves as a single crystal in xpl, | ||
![]() | Petrobrasiella Domed-shaped holococcoliths with holes or cavities. | ||||
![]() | ![]() | Pseudoconus Solid, truncated-cone-shaped nannolith with rectangular cross-section constructed from minute, roughly equidimensional crystallites. Possibly a holococcolith. | |||
Semihololithus Holococcoliths usually seen in side view and comprising a thick proximal plate and spine or process, typically with a cavity or axial canal. | |||||
Stereorhabdus Holoccolith with elliptical base and five-rayed process | |||||
![]() | ![]() | Tanzanella Cavate holococcolith with internal walls and distal protrusions | |||
![]() | Thecatus Cavate holococcolith with box-shape, high rim and thin proximal plate, short spine on distal surface | ||||
![]() | ![]() | unidentified holococcoliths |
Taxonomy:
Farinacci & Howe catalog pages: Rarer genera [no catalog entry yet]
Distinguishing features:
Parent taxon (Holococcoliths): Coccoliths formed of minute (ca 0.1µm) rhombohedral micro-crystals. Often a life-cycle stage with heterococcolith counterpart(s).
This taxon: Less common genera
Search data:
: holococcolith, |
Lith size: 0->0µm; |
Geological Range:
Last occurrence (top): at top of Paleocene Epoch (100% up, 56Ma, in Thanetian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within Toarcian Stage (174.15-182.7Ma, base in Toarcian stage). Data source: Total of ranges of species in this database
Plot of occurrence data:
![]() |
Rarer genera compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 6-12-2023
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=10985 Go to Archive.is to create a permanent copy of this page - citation notes |
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