Vezda, A 1965: Flechtensystematische Studien I. Die Gattung Petractis Fr.. - Preslia37: 127-143. [RLL List # 55 / Rec.# 19549] Keywords: PETRACTIS/ NEW TAXA/ KEY
Abstract: 2 pl. [Key to the 5 species: P. clausa (Hoffm.) Krempelh., P. luetkemuelleri (Zahlbr.) comb. nov., P. hypoleuca (Ach.) comb. nov., P. thelotremella (Bagl.) comb. nov., and P. farlowii (Tuck. ex Nyl.) comb. nov.]