A reassessment of the Pyrenula andina-mastophoroides complex (lichenized Ascomycota: Pyrenulaceae) focusing on the neotropics clarifies taxon concepts and reveals nine new or previously unrecognized species

In the course of a revision of the historical lichen collections of Alexander Lindig from Colombia, housed in the herbaria PC, BM, G, H, M and S, we came across various specimens fitting the broad concept of Pyrenula andina Aptroot and P. mastophoroides (Nyl.) Zahlbr., including the type material. In order to clarify taxon concepts in this complex, we proceeded to revise numerous collections reported as P. andina and P. mastophoroides from the neotropics (Costa Rica, Puerto Rico, Colombia, Ecuador, Bolivia), plus one from the eastern palaeotropics (Papua New Guinea), which are almost all housed in the Herbarium Berolinense (B), with some duplicates in the ABL, COL and CR herbaria (including former INBio collections). Much to our surprise, the studied material revealed a total of 17 species, differing in the absence or presence of lichexanthone and in its location (on the thallus surface or in the medulla), the absence or presence of hamathecium inspersion and its extension (entire hamathecium or parts of it), ascospore type and size, and overall thallus and perithecial morphology. As a result, only the type collections of P. andina (from Costa Rica) and P. mastophoroides (from Colombia) represent these species in a strict sense. All other collections are either misidentifications or represent new species or taxa resurrected from synonymy. Misidentifications include P. adacta Fée, P. dermatodes (Borrer) Schaer., P. diamantinensis C. O. Mendonça, Aptroot & M. Cáceres (new for Costa Rica), P. flavoinspersa Aptroot & Sipman, P. gahavisukana Aptroot (new for Costa Rica, Colombia and Ecuador) and P. quassiicola Fée. Pyrenula mastophoroides var. flavicans (Nyl.) Zahlbr. is removed from synonymy of P. mastophoroides and reinstated as P. flavicans (Nyl.) B. Moncada & Lücking comb. & stat. nov. The following eight species are described as new: P. endoperidermica B. Moncada & Lücking sp. nov. (Costa Rica), P. ferruginea B. Moncada & Lücking sp. nov. (Costa Rica), P. flavascolea B. Moncada & Lücking sp. nov. (Ecuador), P. henrici B. Moncada & Lücking sp. nov. (Papua New Guinea), P. inversa B. Moncada & Lücking sp. nov. (Colombia), P. latens B. Moncada & Lücking sp. nov. (Costa Rica, Colombia), P. tica B. Moncada & Lücking sp. nov. (Costa Rica) and P. xanthomaculata B. Moncada & Lücking sp. nov. (Costa Rica, Colombia). Citation: Moncada B. & Lücking R. 2025: A reassessment of the Pyrenula andina-mastophoroides complex (lichenized Ascomycota: Pyrenulaceae) focusing on the neotropics clarifies taxon concepts and reveals nine new or previously unrecognized species. – Willdenowia 55: 325–355. Version of record first published online on 3 October 2025.