| Name | Cetraria islandica var. tenuifolia (Retzius) Vainio |
| Authorship | (Retzius) Vainio |
| Rank | Variety |
| NomenclaturalStatus | NomLeg |
| Placed in | Cetraria islandica (Linnaeus) Acharius |
| GUID | urn:lsid:indexfungorum.org:names:452215 |
| Citation | 1909 Ark. Bot. 8(4): 21 |
| Holdings | 7 Specimens held in the Harvard University Herbaria identified as Cetraria islandica var. tenuifolia (Retzius) Vainio |
| Identification made in | [no date] (6), 1915 (1) |