Pannaria crispella comb. nov. and P. campbelliana Hue, two overlooked lichens from New Zealand

Abstract

Psoroma sphinctrinum var. crispellum has been considered a synonym of Pannaria implexa, but it is a distinct species, recombined here as P. crispella. It forms a thin, filmy thallus on tree trunks, and consists of rounded, confluent squamules surrounded by a distinct black prothallus. The apothecia are initially simple with a well-defined central thalline plug. However, the plug soon expands into a labyrinth-like structure with undulate margins, unlike those of any other Pannariaceae. The ascospores are long-tailed, as in P. implexa, but otherwise smooth, and the species contains argopsin, very rarely reported from the family except for the parmelielloid clade. Pannaria campbelliana, previously also considered to be a synonym of P. implexa, is shown here to represent a second well-founded species, characterized by thick, geotropically arranged squamules, a distinct fibrous prothallus, apothecia with a prominent simple thalline plug and short-ellipsoid spores lacking apiculate extensions.