Basionym Name:Peltigera canina var. extenuata Nyl. ex Vain., Meddn Soc. Fauna Flora fenn. 12: 49 (1873)
Homotypic synonyms:Peltigera canina subsp. extenuata (Nyl. ex Vain.) Vain., Meddn Soc. Fauna Flora fenn. 6: 129 (1881)Peltigera didactyla var. extenuata (Nyl. ex Vain.) Goffinet & Hastings, Lichenologist 27(1): 48 (1995)Peltigera extenuata (Nyl. ex Vain.) Lojka, Lichenoth. univers., Fasc. 5: no. 222 (1886)