Discoplastis
{{Short description|Genus of algae}}
{{Automatic taxobox
|image =
|image_caption =
|taxon = Discoplastis
|authority = R.E.Triemer, 2006
| type_species = Discoplastis spathirhyncha
| type_species_authority = (Skuja) Triemer{{AlgaeBase genus | id=50751 | title=Discoplastis Triemer, 2006 | access-date=2025-05-04 }}
| subdivision =
- Discoplastis adunca {{Au|(J.Schiller) Triemer}}
- Discoplastis angusta {{Au|(C.Bernard) Zakryś & Łukomska}}
- Discoplastis constricta {{Au|(Matvienko) Zakryś & Łukomska}}
- Discoplastis excavata {{Au|(J.Schiller) Zakryś & Łukomska}}
- Discoplastis gasterosteus {{Au|(Skuja) Zakryś & Łukomska}}
- Discoplastis spathirhyncha {{Au|(Skuja) Triemer}}
}}
Discoplastis is a genus of euglenoid algae belonging to the family Phacaceae.{{cite web |title=Discoplastis R.E.Triemer, 2006 |url=https://www.gbif.org/species/4893670 |website=www.gbif.org |access-date=10 May 2021 |language=en}} The species of this genus are found in Europe, Northern America, Southeastern Asia and Australia.
Discoplastis consists of solitary, free-living cells with one emergent flagellum. The cells have a flexible, spirally striated pellicle and are therefore capable of metaboly. When swimming, the cells are a variety of different but characteristic shapes (cylindrical, fusiform, hourglass-shaped, etc.). The posterior of the cell ends in a pointed, colorless cell. Within each cell there are numerous small, discoid chloroplast lacking pyrenoids. Cells have paramylon grains; the paramylon grains may be monomorphic (all small) or dimorphic (some large, some small).{{cite journal|doi=10.1111/jpy.13107 |title=Description of Flexiglena gen. nov. and new members of Discoplastis and Euglenaformis (Euglenida) |date=2021 |last1=Łukomska-Kowalczyk |first1=Maja |last2=Chaber |first2=Katarzyna |last3=Fells |first3=Alicja |last4=Milanowski |first4=Rafał |last5=Zakryś |first5=Bożena |last6=De Clerck |first6=O. |journal=Journal of Phycology |volume=57 |issue=3 |pages=766–779 |pmid=33205421 |pmc=8248102 |bibcode=2021JPcgy..57..766L }} As with other euglenoids, the cell has a reddish eyespot (stigma).{{cite book |editor-first1=John D.|editor-last1=Wehr|editor-first2=Robert G.|editor-last2=Sheath|editor-first3=J. Patrick|editor-last3=Kociolek |date= 2014 |edition=2 |title= Freshwater Algae of North America: Ecology and Classification |last1= Triemer|first1=Richard E. |last2= Zakryś |first2=Bożena |chapter= Chapter 10. Photosynthetic Euglenoids |url= |location= |publisher= Elsevier Inc. |page= |isbn=978-0-12-385876-4 }}
Discoplastis can be distinguished by to the combination of small, discoid parietal chloroplasts without pyrenoids (a synapomorphy for the family Phacaceae), and its flexibility.{{cite journal|doi=10.1111/j.1529-8817.2010.00910.x |title=Multigene analyses of photosynthetic euglenoids and new family, Phacaceae (Euglenales) |date=2010 |last1=Kim |first1=Jong Im |last2=Shin |first2=Woongghi |last3=Triemer |first3=Richard E. |journal=Journal of Phycology |volume=46 |issue=6 |pages=1278–1287 |bibcode=2010JPcgy..46.1278K }} The similar genus Flexiglena is even more flexible, displaying metabolic movement even when swimming. It is also distinguished by having a large paramylon grain directly adjacent to the stigma.
Molecular phylogenetics suggest the following relationships between species:
{{clade
|1=
{{clade
|1={{clade
|1={{clade
|1={{clade
|2=D. excavata
}}
}}
|2={{clade
|2=D. angusta
}}
}}
|2=D. adunca
}}
}}