Lichens from Monte Pascoal, Bahia, Brazil, with some new pyrenocarpous species and a key to the Pyrenula species from Brazil

Abstract

Abstract. The following seven new species of pyrenocarpous lichens are described from Monte Pascoal in Bahia (Brazil): Astrothelium citrisporum Aptroot, Oliveira-Junior & M.Cáceres, with thallus ochraceous, UV-negative, ascomata fused in hemispherical, concolorous pseudostromata, hamathecium not inspersed, and ascospores submuriform, 5 × 1–2-septate, 35–40 × 18–20 µm, citriform, both ends pointed; A. eustominspersum Aptroot & Oliveira-Junior, with thallus pale greyish olivaceous, UV-negative, ascomata fused, ostiole UV+ yellow, hamathecium inspersed, and ascospores 3-septate, 25–27 × 7–7.5 µm; A. flavogigasporum Aptroot, with thallus olivaceous, UV-negative, ascomata single, ostioles apical, hamathecium yellowish (K-negative) inspersed, and ascospores 4/ascus, hyaline, densely muriform, 240–260 × 33–38 µm, long-ellipsoid, without thickened central septum; A. medioincrassatum Aptroot & M.Cáceres, with thallus olivaceous, UV-negative, ascomata fused in inconspicuous groups, ostioles lateral, hamathecium not inspersed, and ascospores 9–11-septate, 98–115 × 23–27 µm, long-ellipsoid, with thickened central septum; Pseudopyrenula gelatinosa Aptroot, with thallus UV-negative, ascomata solitary, ostioles apical, hamathecium not inspersed, and ascospores 3-septate, 34–37 × 9–10.5 µm, wall 1 µm thick, surrounded by a 9–10.5 µm thick gelatinous sheath; Pyrenula salmonea Aptroot, with thallus salmon pink, ascomata solitary, ostioles apical, hamathecium densely hyaline inspersed, and ascospores 3-septate, uniseriate, 24–27 × 13–16 µm, ellipsoid, lumina oval to somewhat angular, broader than long, without endospore between the outer lumina and the ascospore wall; and P. sanguineoastroidea Aptroot with thallus olivaceous, UV-negative, ascomata fused, deeply immersed in the bark, ostioles lateral, hamathecium not inspersed, and ascospores 3-septate, 24–27 × 10–12 µm, long-ellipsoid, lumina rhomboid, with thick endospore layer between the outer lumina and the ascospore wall. A further 353 species are reported, of which 12 are first records for Brazil and 192 are first records for the state of Bahia, despite it being one of the states of Brazil that is best investigated lichenologically. A graph is presented with the cumulative number of species collected after a certain time of fieldwork. It does not significantly level off, suggesting that many more species occur in the area. A key to the Pyrenula species known from Brazil is presented.