| Name | Lyngbya obscura f. aestivalis Kützing |
| Authorship | Kützing |
| Rank | Forma |
| Placed in | Lyngbya obscura Kützing ex Gomont |
| Holdings | 1 Specimen held in the Harvard University Herbaria identified as Lyngbya obscura f. aestivalis Kützing |
| Identification made in | [no date] (1) |