This is the only extant marine species. According to Algaebase 36 species have been described in Actiniscus, predominantly by Ehrenberg. Of these they regard the following as 'currently accepted'
These names do appear on taxonomic name lists but not in publications on the algae.
Update - as noted by Ines Galovic (see comments) Dumitrica (1973) and Locker & Martin (1986) provided detailed fossil record data on actiniscids, and described several taxa.
Distinguishing features:
Parent taxon (Actiniscus): Dinoflagellate with siliceous internal skeleton formed of two star-like bodies
This taxon: Skeletal bodies are 5-rayed with concavo-convex shape and a sculpted surface
There is an obvious superficial similarity with discoasters but this is most likely coincidental
| Lith size: 0->0µm; |
Geological Range:
Last occurrence (top): Extant. Data source: occurs the plankton
First occurrence (base): within Late Oligocene Sub-Epoch (23.03-28.09Ma, base in Chattian stage). Data source: Dumitrica 1973
Plot of occurrence data:
Dumitrica, P. (1973). Cenozoic endoskeletal dinoflagellates in southwestern Pacific sediments cored during Leg 21 of the DSDP. Initial Reports of the Deep Sea Drilling Project. 21: 819-835. gs O Ehrenberg, C. G. (1840). Uber noch jetzt zahlreich lebende Thierarten der Kreidebildung und
den Organismus der Polythalamien. Abhandlungen der Koniglichen Akademie der Wissenschaften zu Berlin. [1839]: 81-174. gs Ehrenberg, C. G. (1843). Über die verbreitung des jetzt wirkenden kleinsten organischen lebens in Asien, Australien und Afrika und über die vorherrschende bildung auch des oolithkalkes der Juraformation aus kleinen polythalamischen thieren. Bericht uber die zu Bekanntmachung geeigneten Verhandlungen der Koniglichen Preussische Akademie der Wissenschaften zu Berlin. 100-106. gs Locker, S. & Martini, E. (1986). Ebridians and actiniscidians from the southwest Pacific. Initial Reports of the Deep Sea Drilling Project. 90: 941-951. gs References:

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Actiniscus pentasterias compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 14-8-2026
Short stable page link: https://mikrotax.org/Nannotax3/index.php?id=20004 Go to Archive.is to create a permanent copy of this page - citation notes |
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Comments (5)
Please see http://deepseadrilling.org/21/volume/dsdp21_25.pdf
thanks - I will add a reference to that paper.
According to Dumitrica, it is known from Oligocene to recent. Could you revise its base as a fossil, please? Thank you:)
P.S. In the Paratethys it is typical for the Miocene.
Hi Ines
Thank yo for pointing that out - and I have changed it.
Jeremy
Please see: http://deepseadrilling.org/21/volume/dsdp21_25.pdf