Position in a system
| system | Vitae - living organisms |
| domain | Eukaryota Whittaker & Margulis, 1978 - lifeforms with nucletic cells |
| superregnum | Unikonta |
| system | Opisthokonta Cavalier-Smith, 1987 |
| kingdom | Fungi Whittaker - fungi |
| divisio | Ascomycota Caval.-Sm. - sac fungi |
| subphylum | Pezizomycotina O.E. Erikss. & Winka |
| class | Lecanoromycetes O.E.Erikss. & Winka |
| subclass | Lecanoromycetidae |
| order | Peltigerales |
| family | Placynthiaceae |
| genus | Placynthium (Ach.) Gray - blackthread lichen |