Studies in Bacidia sensu lato (lichenized Ascomycetes: Lecanorales) I.: The genus Bapalmuha

The lichen genus Bapalmuia is emended and monographed. Sixteen species are assigned to the genus, seven of which being new to science: Bapalmuia cacaotica Kalb & Lucking spec, nova, Bapalmuia confusa Kalb & Lucking spec. nova, B. costaricensis Lucking & Kalb spec. nova, B. halleana Serus. spec. nova, B. lineata Lucking & Kalb spec. nova, B. sorediata Kalb & Lucking spec. nova, and B. variratae Serus. spec. nova. B. buchananii (Stirt.) Kalb & Lucking comb. nova (= Stereocaulon buchananii), B. callichroa (Mull. Arg.) Kalb & Lucking comb. nova (= Lopadium callichroum), and B. lafayetteana (Vain.) Kalb & Lucking comb. nova (= Bacidia lafayetteana) are new combinations. Bapalmuia kakouettae Serus. is excluded from the genus and Byssoloma aptrootii Serus. is reduced into synonymy with it. Bapalmuia is characterized by biatorine apothecia with strongly convex disc and thin, usually evanescent margin, prosoplectenchymatous excipulum with radiating cell rows or with a labyrinthic structure, unbranched paraphyses, asci with an I+ darker tubular structure in the tholus, needle-shaped to narrowly cylindrical, multiseptate to submuriform ascospores, and small, unseptate, ellipsoid to fusiform conidia. 4,5-dichlorolichexanthone (= coronatone) is the major secundary product in all corticolous and muscicolous and in several foliicolous species. Because of apothecial anatomy and ascus structure, the genus is placed in the Pilocarpaceae. A key to all hitherto known species is provided.