discoaster
{{Short description|Extinct genus of single-celled organisms}}
{{italic title}}
{{taxobox
| name =Discoaster
| fossil_range = {{fossil range |Paleocene |Pleistocene |ref=
{{cite journal
| last = Bukry | first = David
| year = 1971
| title = Discoaster evolutionary trends
| journal = Micropaleontology
| volume = 17 | pages = 43–52 | issue = 1
| publisher = The Micropaleontology Project, Inc.
| jstor = 1485036 | doi = 10.2307/1485036
}} |ps=Most abundant during Miocene }}
| image = Discoaster surculus 01.jpg
| image_caption = Discoaster surculus, about 15 μm across
| domain = Eukaryota
| unranked_phylum = Haptophyta
| classis = Prymnesiophyceae
| ordo = Coccosphaerales
| familia = Coccolithaceae
| genus = {{extinct}}Discoaster
| genus_authority = Tan Sin Hok (1931)
}}
{{commons category|Discoaster}}
Discoaster is a genus of extinct star-shaped marine algae, with calcareous exoskeletons of between 5-40 μm across that are abundant as nanofossils in tropical deep-ocean deposits of Neogene age. Discoaster belongs to the haptophytes. About 100 species can be recognized.
{{cite web
|title=Discoasters
|website=Springer Reference
|publisher=Springer
|url=http://www.springerreference.com/docs/html/chapterdbid/43485.html
|access-date=4 July 2013
}}
Biostratigraphic significance
The International Commission on Stratigraphy (ICS) has assigned the extinction of Discoaster brouweri as the defining biological marker for the start of the Calabrian Stage of the Pleistocene, 1.806 million years ago. ICS has assigned the extinction of Discoaster pentaradiatus and Discoaster surculus as the defining biological marker for the start of the Gelasian Stage, 2.588 million years ago, the earliest stage of the Pleistocene. ICS further assigned the extinction of Discoaster kugleri as biological marker for the start of the Tortonian Stage of the Miocene, 11.62 million years ago.
Species
Some species in this genus include:
{{cite journal
|last1=Raffi |first1=I.
|last2=Mozzato |first2=C.
|last3=Fornaciari |first3=E.
|last4=Hilgen |first4=F.J.
|last5=Rio |first5=D.
|date=Spring 2003
|title=Late Miocene calcareous nannofossil biostratigraphy and astrobiochronology for the Mediterranean region
|journal=Micropaleontology
|volume=49 |issue=1 |pages=1–26
|doi=10.1661/0026-2803(2003)049[0001:LMCNBA]2.0.CO;2
|publisher=The Micropaleontology Project, Inc.
|s2cid=198157383
}}
{{cite web
|last1=Guiry |first1=M.D.
|last2=Guiry |first2=G.M.
|year=2008
|title=Discoaster
|website=AlgaeBase
|department=World-wide electronic publication
|publisher=National University of Ireland
|place=Galway, IE
|url=http://www.algaebase.org/search/genus/detail/?genus_id=45430
|access-date=2009-02-21
}}
:
| + {{big|Discoaster}}
! Species !! Authority | |
| D. asymmetricus | {{small|Gartner}} |
| D. bellus | {{small|Bukry & Percival}} |
| D. berggrenii | {{small|Bukry}} |
| D. bollii | {{small|Martini & Bramlette}} |
| D. brouweri | {{small|Bramlette & Riedel}} |
| D. calcaris | {{small|Gartner}} |
| D. exilis | {{small|Martini & Bramlette}} |
| D. hamatus | {{small|Martini & Bramlette}} |
| D. intercalaris | {{small|Bukry}} |
| D. kugleri | {{small|Martini & Bramlette (1963)}} |
| D. loeblichii | {{small|Bukry}} |
| D. neohamatus | {{small|Bukry & Bramlette}} |
| D. neorectus | {{small|Bukry}} |
| D. pentaradiatus | {{small|(Tan, 1931) Bramlette & Riedel}} |
| D. quintatus | {{small|Gartner}} |
| D. surculus | {{small|Martini & Bramlette}} |
| D. toralus | {{small|Ellis, Lohmann, & Wray}} |
| D. triradiatus | {{small|Tan (1931)}} |
| D. variabilis | {{small|Martini & Bramlette}} |
| D. arneyi | {{center|—}} |
References
{{Reflist|25em}}
{{Taxonbar|from=Q5281570}}
Category:Prehistoric eukaryote genera
Category:Paleocene first appearances
Category:Pleistocene genus extinctions
{{Haptophyte-stub}}