First inventory of lichens from the Brazilian Amazon in Amapa State

Preliminary results are presented of a lichen exploration in Amapa State in Brazil. The following new species are described: Absconditella termitariicola with apothecia immersed to emergent, often partly covered by the thallus, 0.15-0.25 mm diam., pale ochraceous; asci pyriform; ascospores 1-septate, 10-12 x 4.0-5.0 mu m, Astrothelium lineatum with orange thallus with orange, often linear pseudostromata with immersed ascomata in groups of 3-15; ascospores 8/ascus, hyaline, regularly muriform, 45-55 x 11-13 mu m, without distinctly thickened median septum, Astrothelium unisporum with thickly corticate thallus, high, thallus-covered pseudostroma warts with 1-4 ascomata; ascospores 1/ascus, muriform, 125-148 x 35-42 mu m, Coenogonium minidenticulatum with apothecia 0.2-0.4 mm diam., usually distinctly denticulate; ascospores 6-7 x 1.0-1.5 mu m, with rounded ends, Crypthonia corticorygmoides with olive green felty thallus, up to 1 cm large white stromatoid-like ascigerous areas and 3-5-septate clavate ascospores of 25-29 x 5-6 mu m, Cryptothecia rhizophora with white thallus with long, branching, superficial rhizomorphs of up to 0.2 mm wide, which reach until in the prothallus and ascigerous areas with lichexanthone; ascospores 85-95 x 32-37 mu m, Endocarpon riparium with thallus consisting of dense agglutinated flat squamules which are not overlapping, with margins and cracks with numerous 0.1-0.2 mm diam. dorsiventral lobules of thallus-structure that are easily detached and serve as asexual propagules, Psammina tropica with sporodochia abundant in the central part of the thallus, absent in a marginal zone of 1-2 mm wide, whitish grey, irregular to rounded, ca. 0.1-0.3 mm diam., only ca. 15 mu m high; conidia hyaline, palmate, with 3-6 arms, each of which are 4-7-celled, ca. 20-25 mu m diam., consisting of cells of ca. 2.5-3.0 mu m, Thelenella monospora with shiny grey thallus, low conical thallus-covered ascomata and ascospores 1/ascus, hyaline, ellipsoid, irregularly muriform, 75-90 x 25-28 mu m, and Thelocarpon triseptatum with minute pallid perithecioid ascomata with flat tops, hamathecium thin anastomosing paraphysoids; ascospores 8/ascus, 3-septate, 12-16 x 3.5-4.5 mu m. A further 209 species are reported new to Amapa State, eight are new to the Neotropics, one is new to South America and a further seven are new to Brazil. In Amapa, just as in Rondonia, Astrothelium is the most speciose lichen genus, and this may be the case all over the Amazon.