Cosmiodiscus

{{Short description|Extinct genus of single-celled organisms}}

{{Automatic taxobox

| fossil_range = {{fossil range|5.33|3.6}}

| image =

| image_caption =

| taxon = Cosmiodiscus

| authority = Greville, 1866

| subdivision_ranks = Species

| subdivision =

• †Cosmiodiscus barbadensis Greville
• †Cosmiodiscus beaufortianus Hustedt
• †Cosmiodiscus elegans Greville, 1866
• †Cosmiodiscus elegans var. inermis
• †Cosmiodiscus insignis A.P.Jousé

}}

Cosmiodiscus is an extinct genus of diatom.{{Cite journal |last=Sullivan |first=Michael J. |date=1983-09-01 |title=Transfer of the marine fossil diatom Cosmiodiscus beaufortianus Hust. to the genus Actinocyclus |url=https://doi.org/10.2216/i0031-8884-22-3-277.1 |journal=Phycologia |volume=22 |issue=3 |pages=277–284 |doi=10.2216/i0031-8884-22-3-277.1 |bibcode=1983Phyco..22..277S |issn=0031-8884|url-access=subscription }}