LICHENICOLOUS FUNGI OCCURRING ON ROCCELLACEAE (ARTHONIALES) I. NEW SPECIES FROM SOUTH AMERICA

Abstract

  Seven lichenicolous ascomycetes are described as new species living on South American Roccellaceae s. str. Three of these form part of the Arthoniaceae (1. Arthonia darbishirei Follm. & Wern. sp. nov. on Roccella nigerrima [Darb.] Follm., 2. A. ingaderiae Follm. sp. nov. on Ingaderia gracillima [Kremp.] Feige & Lumbsch and A. pulcherrima Darb., 3. A. prominens Follm. sp. nov. on I. gracillima [Kremp.] Feige & Lumbsch), four appertain to the Opegraphaceae (4. Lecanographa imitans Wern. & Follm. sp. nov. on Roccella humboldtiana Follm., 5. Opegrapha perturbans Follm. sp. nov. on I. pulcherrima Darb., 6. O. reinkellae Follm. sp. nov. on R. lirellina [Darb.] Follm., 7. Plectocarpon labyrinthicum Follm. sp. nov. on R. portentosa [Mont.] Darb.). Hence, the roccellicolous fungi observed share various basic characters with their hosts in the order Arthoniales. This is supposed to be the main reason why the fructifications of four of them (1, 2, 5, 6) were confused with genuine ones of their hosts in former times. Four species originate from Chile (2, 3, 5, 7), two from the Galapagos Islands (1, 4) and one from Perú (6). All hosts mentioned constitute endemics, but their fungal commensals (5), parasymbionts (1, 2) and parasites (3, 4, 6, 7) occupy throughout smaller areas of distribution. It is emphasized that the Roccellaceae s. str. are not as poor in lichenicolous fungi as generally accepted. The recently discovered representatives of roccellicolous ascomycetes are compared with the few hitherto known ones from other floral regions, and their joint developmental, symbiological and biogeographical traits, including taxonomical and nomenclatural problems, are briefly discussed.