| Name | Cosmarium lundellii f. crassangulatum A. M. Scott & Prescott | 
| Authorship | A. M. Scott & Prescott | 
| Rank | Forma | 
| NomenclaturalStatus | NomLeg | 
| Placed in | Cosmarium lundellii Delponte | 
| Citation | 1961 Hydrobiologia 17(1/2): 61 | 
| Holdings | 1 Specimen held in the Harvard University Herbaria identified as Cosmarium lundellii f. crassangulatum A. M. Scott & Prescott | 
| Identification made in | [no date] (1) |