Lichenologist 27(1): 25–42 (1995) A P RELIMINARY ACCOU NT OF THE LICHENICOLOU S AR T HO NIA S P ECIES WITH RED D IS H, K+ REACTIVE P IGMENTS M. GRU B E*, M. MATZER* and J. HAFELLNER* Abstract: D escriptions and a key for identification of lichenicolous A rthonia species with red to purple pigments reacting with K are provided. T he previously reported species, A . cryptotheciae and A . maz osiicola (as A . maz osiae), are here validly described, and A . haematostigma, A . tavaresii and A . destruens var. nana are new to science. T he genus H elicobolomyces is introduced with the type species H . lichenicola, being based on the anamorph of A . cinnabarinula. Introduction A rthonia Ach. is one of the largest genera of crustose lichens and comprises more than 500 species according to the current concept. T he status of many principally tropical taxa is still unclear and a comparative treatment is urgently needed. Additionally, the interrelationships between species arranged into different subgeneric taxa are poorly understood. H owever, the disposition of species into more or less artificial taxonomic groups (e.g. Redinger 1937) may serve as a basis for future work directed at providing a more natural arrangement. One of the subgeneric units, subsection Coniocarpon (D C .) Stein, is characterized by coloured (not black) ascomata with pigments that show a reddish to violet reaction with alkaline solutions (e.g. KOH ). T his group shows a wide ecological range including several lichenicolous fungi. F ormerly, lichen parasitic species of A rthonia were placed into the genera Conida M assal., and Celidium T ul. T hese two genera were distinguished by differences in spore septation (one-septate in Conida, pluriseptate in Celidium), but due to the lack of other characters Santesson (1952) synonymized Conida and Celidium with A rthonia. H e mentioned three lichenicolous A rthonia species that exhibit reddish, K + reactive pigments, namely A . cinnabarinula, A . cryptotheciae and A . maz osiicola (as A . maz osiae). H owever, the last two species were not validly described (IC BN , Art. 36.1) as Santesson planned to include the lichenicolous species in an anticipated second part of his revision of foliicolous lichens. N o additional species were indicated to have reddish pigments in the key recently compiled by C lauzade et al. (1989), which incorporated 48 lichenicolous A rthonia spp. In this paper we include valid descriptions and present all known species possessing reddish, K + reacting pigments. It should be emphasized that neither these fungi nor the lichenized species of the subsection Coniocarpon represent a single natural group (a new arrangement will be proposed later; G rube, unpublished data). T his is underlined by the variety of reddish *Institut für Botanik, Karl-F ranzens-U niversität, H olteigasse 6, A–8010 G raz, Austria. 0024–2829/95/010025 + 18 $08.00/0 ? 1995 T he British Lichen Society 26 T H E LIC H EN OLOG IST Vol. 27 pigments in Coniocarpon, which may be either crystalline or amorphous and in addition vary by their reaction with K as well (G rube 1991). H owever, these characters are constant within the species and useful in diagnostic keys. Within the order Arthoniales red (quinoid) pigments are also known from A rthothelium M assal., Cryptothecia Stirton, Erythrodecton T hor and Opegrapha Ach. Materials and Methods D imensions, given in micrometres, were measured in water, except for those of conidia, which were studied in ammoniacal erythrosin. T he studied specimens are cited together with the treated species. Key to the Species 1 On foliicolous lichens . . . . . . . . . . . . . . . . . . . . . 2 N ot on foliicolous lichens . . . . . . . . . . . . . . . . . . . 4 2(1) Ascomata superficial from the beginning, often whitish pruinose, epithecioid layer distinct. Ascospores 9–14 #3–5 ìm, 2–3-septate (F ig. 1D ). On Cryptothecia . . . . 4. Arthonia cryptotheciae Ascomata erumpent, never pruinose, epithecioid layer indistinct. Ascospores 1-septate . . . . . . . . . . . . . . . . . . . . 3 3(2) Ascomata dark reddish brown. Ascospores 7–10 #1·5–3 ìm (Fig. 4C ). On M az osia . . . . . . . . . . . . . 7. A. m azosiicola Ascomata bright orange to orange-red. Ascospores 5–11 #2–4 ìm (F ig. 1A). On Porina and T richothelium . 1. A. cinnabarinula 4(1) Ascomata &stellate, dark blood red pruinose. Ascospores 17– 23 #7–8 ìm, 2–3-septate, brown (Fig. 2B). On ‘ A nthracothecium ’ and Parmentaria . . . . . . . . . . . . . . . 10. A. tavaresii Ascomata &roundish . . . . . . . . . . . . . . . . . . . . . 5 5(4) Ascomata blood-red or orange-red . . . . . . . . . . . . . . 6 Ascomata dark reddish brown to black . . . . . . . . . . . . 7 6(5) Ascomata blood-red. Pigments distinctly crystallized. Ascospores 6–8·5 #1·5–2·5 ìm (Fig. 4B). On Ramalina . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6. A. haem atostigm a Ascomata orange-red. Pigments amorphous or partly granular. Ascospores 11·5–15 #4–6·5 ìm (Fig. 2A). On Pseudocyphellaria . . . . . . . . . . . . . . . . . 9. A. pseudocyphellariae 7(5) Without distinct epithecioid layer. Ascospores 12–14 #5–6 ìm (Fig. 1C ). On A rthothelium . . . . . . . . . . . . 3. A. cohabitans With distinct epithecioid layer . . . . . . . . . . . . . . . . 8 8(7) Ascospores 7–10 #3–4 ìm (Fig. 4D ). Ascomata scattered. On a sterile, sorediate crust . . . . . . . . . . . 8. A. neglectula Ascospores larger . . . . . . . . . . . . . . . . . . . . . . . 9 1995 Lichenicolous A rthonia— Grube et al. 27 F . 1. Ascospores. A, A rthonia cinnabarinula (M atz er 1511). B, A . circinata (lectotype). C , A . cohabitans (topotype). D , A . cryptotheciae (Lücking 92–72). Scale = 10 ìm. 9(8) Ascomata arising in circular infection spots in progressive infections, in section commonly with granular red pigment. Ascospores 11–14 #4–6 ìm (Fig. 1B). On Umbilicaria . . 2. A. circinata N ot in circular spots, in section with amorphous yellowish pigment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 10(9) Ascomata crowded. Ascospores 10·5–17 #5–7 ìm (Fig. 4A). On Physcia . . . . . . . . . . . . . . . . . . . 5. A. destruens Ascomata dispersed. Ascospores 10·5–13 #5–7. On X anthoria . . . . . . . . . . . . . . . . . . . 5a. A. destruens var. nana The Species 1. Arthonia cinnabarinula Müll. Arg. Flora 64: 234 (1881); type: Brazil, Apiahy, on Porina cf. tetramera, Puiggari 384 pr.p., L.B. n. 307 (G !—holotype, isotype [‘384 pr.p.’ not indicated]). Cryptodiscus aurantiacoruber Rehm, H edwigia 39: 82 (1900), as ‘C. aurantiaco-ruber’; type: Brazil, Auf F arnwedel, E. Ule 863 c (S!—holotype). (F ig. 1A) A scomata scattered or crowded, erumpent from the host thallus, rounded or elongated, usually simple, up to 0·4 mm diam., orange or bright red; in section 40–70 ìm tall. Parathecioid layer indistinct. Epithecioid layer hyaline to 28 T H E LIC H EN OLOG IST Vol. 27 yellowish, 5–15 ìm tall. Ascigerous layer hyaline, yellow, or light orange, 30–40 ìm tall. H ypothecioid layer not always distinct, orange, up to 10 ìm tall. Interascal filaments paraphysoidal, branched and anastomosed, c. 1 ìm thick. A sci (shortly) clavate, 17–27 #9–14 ìm, with distinct stipe, 8-spored, lacking I + and KI + structures in the tholus. A scospores oblong ovoid, hyaline, becoming pale brown when over-mature, halonate or not, (5–)7–10(–11) #2– 4 ìm, 1-septate, not constricted at the septum (Fig. 1A). V egetative hyphae indistinct. Chemistry: Ascigerous and hypothecioid layer I + deep red, KI + deep blue. Yellow to orange pigment turning violet and dissolving in K. Life form: Lichenicolous, apparently not damaging the host; on foliicolous T richotheliaceae: Porina epiphylla (Fée) Fée, P. fulvella M üll. Arg., P. cf. tetramera (M alme) R. Sant. in T horold, T richothelium epiphyllum M üll. Arg., T richothelium species. Remarks: F or the coelomycetous anamorph of A . cinnabarinula, generic and species descriptions are provided as follows: Helicobolom yces Matzer gen. nov. C onidiomata aurantiaca ad fusca, K + violacea, ostiolis instructa. C onidiophora hyalina, septata. C ellulis conidiogenis holothallicis terminalibus. C onidiogenesis terminalis. C onidia primum hyalina demum fuscidula, helicoidea, septata, strato gelatinoso hemiamyloideo circumdata. T ypus generis: H elicobolomyces lichenicola M atzer. Conidiomata rounded, flat or convex, brown to orange above, with a rather wide opening. In longitudinal section laterally with hyaline to brownish, septate and branched hyphae covered by an orange to red pigment; at base with a thin layer. Conidiophores formed from the lateral hyphae of the conidiomata, usually hyaline, branched only at the base, septate. Conidiogenous cells holothallic, integrated, terminal, usually hyaline, oblong, forming conidia apically. Conidia light coloured when mature, roundish to oblong in outline, composed of a few to many cells arranged in a helical chain; single cells small, isodiametric or shortly oblong, smooth; gelatinous material is deposited around the conidia and in the gaps of the helical chain. Chemistry: C entrum of conidiomata and gelatinous material of the conidia I + red, KI + blue. C onidiomata K + dark violet to blackish; orange pigment turning violet and dissolving in K. Helicobolom yces lichenicola Matzer sp. nov. C onidiomata lichenicola, ut descripta, 0·02–0·075 mm diam. C onidiophora 1–2 ìm lata. C onidia 5–18 #5–9 ìm magna, cellulis 2–4(–5) ìm diam. T ypus: C osta Rica, San José province, C ordillera de T alamanca, trail from the village San G erardo de Rivas up to the C erro C hirripó, c. 1700–2200 m, 9)28*N , 83)35*W, tropical montane rain forest, on Porina epiphylla, 1991, M . M atz er[1512] & B. Pelz mann (G ZU —holotype). (F ig. 2C , 3) 1995 Lichenicolous A rthonia— Grube et al. 29 F . 2. A, A rthonia pseudocyphellariae (W edin 2293), ascospores. B, A . tavaresii (holotype), ascospores. C , H elicobolomyces lichenicola (M atz er 1511), conidia. Scale = 10 ìm. Conidiomata lichenicolous, together with the teleomorph on the same host thallus or separate, erumpent from the host thallus, remaining immersed or becoming more or less prominent, rounded, flat or convex, dark reddish brown to orange, scattered, 0·02–0·075 mm diam; in section 15–70 ìm tall. Laterally with hyaline to brownish, 1–2 ìm wide, septate and branched hyphae covered by an orange to red pigment; centrum filled with numerous conidia (F ig. 3A), gel between the conidia hyaline to pinkish; at base with a thin, &hyaline layer. Conidiophores formed from the lateral hyphae of the conidiomata, projecting towards the centrum, usually hyaline but more or less covered by the orange to red pigment, 1–2 ìm wide, branched only at the base. Conidiogenous cells integrated, usually hyaline, oblong, forming conidia apically; conidial initials in the form of hyaline, non-septate, coiling hyphal ends (F ig. 3C ). Conidia light brown when mature, roundish to oblong in outline, composed of few to many cells arranged in a helical chain; single cells 2–4(–5) ìm diam.; conidia 5–18 #5–9 ìm (Figs 2C , 3B). Chemistry: See generic description. Remarks: A rthonia cinnabarinula was described as a lichen by M üller Argoviensis (1881) but it was later recognized to be a lichenicolous fungus by Santesson (1952). It is a pleomorphic ascomycete readily distinguished by orange to bright red ascomata, small and 1-septate ascospores, and a coelomycetous anamorph forming peculiar conidia. T he relationship between A . cinnabarinula and H . lichenicola is evident from the following observations. T he same orange pigment, turning violet and dissolving in KOH was constantly found to be present in both the ascomata and conidiomata, and the gelatinous material in ascomata and conidiomata reacts I + red, KI + blue. In 30 T H E LIC H EN OLOG IST Vol. 27 F . 3. H elicobolomyces lichenicola (M atz er 1511). A, conidioma in cross section; B, C onidia; C , C onidiophores with young conidia. M edium: lactic acid-cotton blue. Scales: A & C = 20 ìm; B = 10 ìm. addition, the perfect and imperfect state were repeatedly found side by side on the same host thallus. T he morphological and chemical characters of H . lichenicola are unique and the species could not be placed in one of the genera of coelomycetes described so far. 1995 Lichenicolous A rthonia— Grube et al. 31 T he original description and the illustrations of Cryptodiscus aurantiacoruber (Rehm 1900) clearly represent an ascomycete with orange-red apothecia. T he author interpreted the fungus to be a parasite growing in a white tissue covering the leaf surface. G rowing together with the type of C. aurantiacoruber were found several species of foliicolous lichens including Porina epiphylla var. epiphylla infected by H . lichenicola. N one of the lichenized species fits the description of C. aurantiacoruber. It is concluded here that in the original material, ascomata of A . cinnabarinula were also present but all were destroyed during the preparation of the protologue or later examinations of the specimen. C onsequently, C. aurantiacoruber is treated as a synonym of A . cinnabarinula, following Santesson (1952: 50). Several passages of the original description and the illustrations provided by Rehm (1900) do not coincide with the characters present in A . cinnabarinula (see description above) and thus are apparently observation errors. So far as is known, A . cinnabarinula occurs in tropical rain forests of America and Southeast Asia. A dditional selected specimens examined: Costa Rica: S an José province: C ordillera C entral, Braulio C arillo N ational Park, La Botella-T rail, c. 750–800 m, 10)09*N , 83)58*W, on Porina epiphylla, (with H elicobolomyces lichenicola on Porina epiphylla and T richothelium sp.), 1991, M . M atz er [1511] & B. Pelz mann (G ZU ); C ordillera de T alamanca, trail from the village San G erardo de Rivas up to the C erro C hirripó, c. 1700–2200 m, 9)28*N , 83)35*W, on T richothelium epiphyllum, 1991, M . M atz er [1523] & B. Pelz mann (G ZU ); Cartago province: E of the city of C artago, on the left side of the road from Paraiso to C ervantes, c. 5 km behind Paraiso, c. 1500 m, 9)53*N , 83)50*W, on Porina fulvella, (with H elicobolomyces lichenicola), 1991, M . M atz er [1513] & B. Pelz mann (G ZU ).—B razil: São Paulo, Serra do M ar, Serra do G arrãozinho, between M ogi das C ruzes and Bertioga, 800 m, on Porina epiphylla, 1979, K . K alb & J. Poelt (G ZU ).— Indonesia: Java, T jibodas, 1500 m, on sterile thallus, 1898, E. N yman (U PS). 2. Arthonia circinata Th. Fr. Bot. N otiser 1865: 100 (1865).—Lecideopis circinata (T h. F r.) Zopf, H edwigia 35: 328 (1896).— Conida circinata (T h. F r.) Sacc. & D . Sacc., S yll. Fung. 18: 188 (1906); type: N orway, F innmark, Alten, Bosekop, på Kognshavnfjeldet, on Umbilicaria vellea, 3 vi 1864, T h. M . Fries (U PS!— lectotype). (F ig. 1B) A scomata in rings of 10–30, &confluent, round, 0·1–0·24 mm diam., sessile, cushion-like and well-delimited, black, with rough surface, 90–110 ìm tall. Parathecioid layer similar to epithecioid layer. Epithecioid layer brown, 8–30 ìm tall, cells 4–6 ìm diam., apically with swollen wall and pigment caps. Ascigerous layer brownish with age, 20–30 ìm tall, occasionally (old infections?) with integrated crystallized orange-red grains. H ypothecioid layer hyaline, brownish with age, 30–40 ìm tall; cells 3–4 ìm diam., slightly roundish to reniform, densely conglutinate. Interascal filaments paraphysoidal, 2 ìm thick and distinct in young ascomata, branched and anastomosed, scanty and collapsed in old ascomata, cells c. 3–5 #1–2 ìm. A sci clavate, 20–35 #10–15 ìm, with indistinct foot, 8-spored, lacking I + or KI + structures in the tholus. A scospores ellipsoid to oblong ovoid, 1-septate, hyaline, perispore indistinct, 11–14 #4–6 ìm, 1-septate, upper cell slightly larger, (not or) slightly constricted at the septum (Fig. 1B). V egetative hyphae not distinct; 32 T H E LIC H EN OLOG IST Vol. 27 mycelium causing regularly roundish spots in progressive infections; infection spots dispersed to confluent, with &constant concentric zonation, an outer zone brownish black, sometimes bleaching, the median zone reddish brown with ascomata arranged in a ring, the central zone pale brown to bleaching and necrotic, often with reddish grains. Chemistry: Ascomatal gels I + reddish, KI + deep blue. Orange-red grains K + turning red-violet, more or less unsoluble. Life form: Lichenicolous, parasitic; on Umbilicaria africana (Jatta) Krog & Swinscow, U. crustulosa (Ach.) Frey, U. hirsuta (Sw. ex Westr.) H offm., U. spodochroa (H offm.) D C ., and U. vellea (L.) Ach. Remarks: A rthonia circinata was studied in detail by H awksworth (1991), who worked out the differences from another lichenicolous species on Umbilicaria H offm., viz. A . rufidula (H ue) D . H awksw., R. Sant. & Øvstedal, a species first described in the monotypic genus Charcotia H ue. A rthonia circinata, distinguished from A . rufidula by the infection symptoms and blunt-ended spores, is known from Sweden, N orway, Austria and U ganda (H awksworth 1991). A rthonia circinata is a parasite and causes necrotic patches on the host thallus in progressive infections. T he species is well developed only on very old thalli of Umbilicaria and then it shows the typical ring-like arrangement of ascomata. T he material cited from U. crustulosa and U. hirsuta exhibits a young infection as the ascomata arise only in small groups and the orange pigments are missing. T he species is included although it is very doubtful whether the red pigments are a product of the lichenicolous fungus. Red spots on old thalli of Umbilicaria species can occasionally be seen without further indications of fungal infections, and it cannot be excluded that the red pigments are products of the host in response to infections. A dditional specimens examined: Norway: Sör-T röndlag, Opdal par., Kongsvold, on Umbilicaria vellea, 1870, J. E. Zetterstedt (U PS).—Austria: Kärnten, N ational Park N ockberge, Rosennock, 2400 m, Blockmeer, Schiefergneis, auf Umbilicaria crustulosa, 1990, W . Petutschnig (G ZU ).— S pain: G erona, Pyrenäen, N aria N Ribas de F reser, c. 2100–2200 m, auf Umbilicaria hirsuta, 1983, J. H afellner 17654 (hb. H afellner). 3. Arthonia cohabitans Coppins Lichenologist 21: 211 (1989); type: G reat Britain, C aledonia, V.C . 98, Argyll M ain, Seil, Ballachuan, Pòrt M òr, 17/76-15-, Corylus, on A rthothelium reagens, 5 viii, 1980, P. W. James (BM —holotype, not seen); ibidem, 7 viii 1980 (G ZU !—topotype). (F ig. 1C ) A scomata crowded (rarely with confluent initials), on thallus, but sometimes growing also on the ascomata of the host, roundish, 0·12–0·24 mm, erumpent and &sessile, cushion-like, reddish brown (darker at the margins when moist), with &rough surface, somewhat shiny, epruinose, in section 60–80 ìm tall. Parathecioid layer indistinct. Epithecioid layer developed only in young 1995 Lichenicolous A rthonia— Grube et al. 33 ascomata, yellowish, 5–10 ìm tall, becoming discontinuous and hyphae becoming gelatinized. Ascigerous layer yellowish brown by amorphous pigments. H ypothecioid layer brownish (pigments intercellular and partly fine granular), 10–20 ìm tall. Interascal filaments paraphysoidal, in mature ascomata evanescent, in young ascomata typically branched and anastomosed. A sci clavate, 28–35 #12–17 ìm, 6–8-spored, epiplast sometimes with yellowish contents, aborted asci often with brownish contents; tholus with very minute or reduced KI + bluish ring. A scospores obovate, greyish brown to brownish, brownish verruculose when mature, 12–14 #5–6 ìm, 1-septate, upper cell slightly larger, slightly constricted at the septum; aborted spores with dark orange-coloured contents (Fig. 1C ). V egetative hyphae not distinct. Pycnidia globose to broadly ellipsoid, 30–50 ìm, brown, basally paler. C onidiogenous cells short, conidia acrogenous, bacilliform, c. 5 #1 ìm. Chemistry: Ascomatal gels I + pale blue, KI + distinctly blue, yellowish pigments K + turning purplish violet (especially cell contents), not dissolving, brownish pigments K + sordid grey. Life form: Lichenicolous, apparently not damaging the host; on A rthothelium reagens (C oppins & James) C oppins & James. Remarks: T his species is hitherto known only from Scotland, where it occurs in strongly oceanic habitats, accompanied by T helotrema sp. and Radula sp., for example. A rthonia cohabitans apparently does not damage the host and might be interpreted as being commensalistic. 4. Arthonia cryptotheciae R. Santesson ex Matzer & R. Santesson sp. nov. Ascomata supra thallum Cryptotheciae ( candidae) formata, dispersa ad gregaria, sessilia, rotundata ad oblonga, 0·1–0·25 mm in diametro, discis fuscis sed frequenter obtectis pruina alba et lateraliter pigmento rubro K + violaceorufo incrustata. Epithecium fuscum. H ymenium hyalinum, 30–50 ìm altum, I + caeruleum. H ypothecium rufofuscum. F ilamenta interascalia ramosa et anastomosantia. Asci clavati, 28–40 #10–17 ìm magni, octospori, stipitati, fissitunicati. Ascosporae hyalinae, halonatae, 2- ad 3-septatae, 9–14 #3–5 ìm magnae. T ypus: T rinidad, Port of Spain, M araval Valley, on Cryptothecia candida, 1913, R. T haxter (U PS—holotype). (F ig. 1D ) A scomata scattered to crowded or confluent, sessile, roundish to oblong, aggregates sublobate, single ascomata 0·1–0·25 mm, aggregates up to 0·5 mm diam.; disc dark brown to blackish, often but not always covered by a white pruina, ascomata laterally covered by shortly projecting hyphae usually encrusted with a red pigment; in section 40–100 ìm tall. Parathecioid layer distinct, 10–30 ìm thick, composed of brown, reticulated hyphae that are more or less encrusted with hyaline crystals, cells 5–8 #1–3 ìm; parathecioid layer especially below with a red, &crystallized pigment. Epithecioid layer brown, up to 15 ìm tall; hyphae interwoven, branched, partially encrusted with hyaline crystals. Ascigerous layer &hyaline, 30–50 ìm tall. H ypothecioid 34 T H E LIC H EN OLOG IST Vol. 27 layer mainly brown but with a red, &crystallized pigment, up to 50 ìm deep, composed of brown, loosely reticulated hyphae. Interascal filaments paraphysoidal, branched and anastomosed (especially in upper ascigerous layer), slender, &collapsed in mature ascomata, cells c. 3–4 #1–3 ìm. A sci clavate, 28–40 #10–17 ìm, with distinct stipe, 8-spored, lacking I + and KI + structures in the tholus. A scospores oblong ovoid, hyaline, halonate, 9–14 # 3–5 ìm, 2- or 3-septate, with the upper cell enlarged, primary septum laid down in or below the middle, then the lower hemispore is divided by one or two further transsepta, spores not constricted at the septa (Fig. 1D ). V egetative hyphae&indistinct. Chemistry: Ascigerous layer I + blue, blue-green reddish, sordid yellow, or olive-brown, K/I + blue. Red pigment dissolving in K, solution red (to violet) in colour. Life form: Lichenicolous, apparently not damaging the host; on Cryptothecia candida (Krempelh.) R. Sant. Remarks: A rthonia cryptotheciae is restricted to the foliicolous lichen C. candida (Arthoniaceae). It was included and illustrated in the study of Santesson (1952; drawing of the habit on p. 66) but a valid description was not given. T he species is readily distinguished by the superficial, sharply delimited ascomata with dark but often whitish pruinose discs and red lateral parts, by the red, &crystallized pigment, and by the 2- or 3-septate, macrocephalic ascospores. U ntil now this conspicuous fungus is known only from two localities in tropical America. A dditional selected specimens examined: Costa Rica: H eredia province, La Selva protection zone, about 60 km N of San José, base of Atlantic slope of the C ordillera C entral, 10)26*N , 84)03*W, c. 50 m, 1992, R. Lücking 92–72 (G ZU , hb. Lücking). 5. Arthonia destruens Rehm in Rabenh. Lich. Eur.: 816 (1868).—Conida destruens (Rehm) Rehm apud Rabenh., K ryptfl. Deutschl. 2. Aufl. 1/3: 423 (1891); type: G ermany, ‘ Auf dem T hallus und dem Apothecialrand von Parmelia stellaris und var. an den Aesten alter H olzbirnbäume auf den Aeckern bei Obernesselbach (Sugenheim) in F ranken, 1867, Rehm ’ (Rabh., Lich Eur. no. 816. S!—lectotype, hoc loco determinavit). (F ig. 4A) A scomata scattered to crowded in groups of about ten, then often confluent, roundish to irregularly roundish, 0·1–0·25(–0·4) mm diam., erumpent from the host thallus and becoming sessile, cushion-like, blackish (also when moist), with a rough surface, in section 50–100 ìm tall. Parathecioid layer formed by a down-turning epithecioid layer, occasionally forming ‘thalloconidia’ at the periphery. Epithecioid layer brownish (intercellular and intralaminar granular pigment) with a yellowish tinge, 5–15 ìm tall, composed of dense, but not interwoven, &anticlinal cells, covered by a 5 ìm tall, hyaline gelatinous coat; cells c. 5 ìm diam. Ascigerous layer yellowish (containing amorphous pigments), 25–50 ìm tall. H ypothecioid layer brown with a yellowish tone, 20–45 ìm tall, composed of&roundish cells, pigmentation as 1995 Lichenicolous A rthonia— Grube et al. 35 F . 4. Ascospores. A, A rthonia destruens var. destruens (lectotype). B, A . haematostigma (holotype); C , A . maz osiicola (M atz er 1532); D , A . neglectula (holotype). Scale = 10 ìm. in the epithecioid layer; cells 3–4 ìm diam.; often with integrated groups of algae, which are densely entwined by hyphal cells. Interascal filaments paraphysoidal, scanty, occasionally branched and anastomosed; cells 4–5 #0·7 –1 ìm. A sci clavate, 29–43 #11–15 ìm, with indistinct foot, 4–8spored, lacking any I + or KI + structures. A scospores oblong-ovoid, becoming brown and verrucose, 10·5–17 #5–7 ìm, 1-septate, slightly constricted at the septum and with a slightly larger upper cell (Fig. 4A). V egetative hyphae indistinct. ‘ T halloconidia ’ occasionally formed at the periphery of the ascomata, roundish, not septate, c. 3·5–5 ìm diam. Chemistry: Epithecioid layer and ascigerous layer I + dark and sordid blue; hypothecioid layer I + reddish brown; all parts KI + deep blue; yellowish pigments K + turning purplish violet and dissolving. Life form: Lichenicolous, locally parasitic; in progressive infections the host thallus bleaches locally and occasionally has a reddish tone due to pigments of the ascomata of the parasite; on Physcia stellaris (L.) N yl., Physcia aipolia (Ehrh. ex H umb.) Fürnr. (the parasites on Physcia adscendens (Fr.) H . Olivier and X anthoria parietina (L.) T h. Fr., often cited as hosts, are presumably not conspecific). Remarks: T he A rthonia that is found on P. adscendens in the type collection of A . destruens and the taxon on X . parietina are different from A . destruens, as indicated by the absence of yellowish K + reactive pigments, I + red reaction 36 T H E LIC H EN OLOG IST Vol. 27 of the ascomata and hyaline, smaller spores. In Arnold, Lich. exs. 397, the form on X . parietina was given the name A . destruens var. maculans Rehm (nom. nud.). T his taxon is probably referable to either A . epiphyscia N yl. (see also Santesson 1960: 501) or A . molendoi (H eufl. ex Frauenf.) R. Sant. A rthonia destruens is parasitic and weakens the host lichen with the infected parts sometimes becoming chlorotic. Algal cells are integrated in the lower parts of the ascomata, and they may have a nutritional function for the parasite. T he parasitic A rthonia on Lecanora leptacina Sommerf. from G reenland (Alstrup & H awksworth 1990: 16) is different in the pigmentation as well as in other characters, and clearly does not belong to A . destruens. It should be compared with the material from the C airngorms cited by C oppins (1992: 79) as A . clemens (T ul.) T h.F r. A dditional specimens examined: Austria: S teiermark: G esäuse-G ebiet, Johnsbach, c. 0·5 km E des G asthofs Kölbl, c. 875 m, G rundfeld 8453/4, an Fraxinus excelsior, auf Physcia stellaris, 1988, J. H afellner [20296] & E. S chreiner (G ZU , hb. H afellner); H ochschwab-G ruppe, an der Straße von T hörl zum G hf. Bodenbauer, kurz vor dem M oarhaus c. 2·5 km N W von Innerzwain, c. 840 m, am Straßenrand, an T ilia, auf Physcia stellaris, 1985, J. H afellner 13335 (G ZU , hb. H afellner); H ochschwab-G ruppe, Seetal W von Seewiesen, c. 10 km N E von Aflenz, 930 m, an alten, freistehenden S alix-Sträuchern, auf Physica stellaris, 1985, J. H afellner & A . Ochsenhofer (hb. H afellner, hb. Kalb; material distributed in Santesson, F ungi lichenicoli exs. no. adhuc ined.); K ärnten: N ational Park H ohe T auern, Aichhorn ca. 4 km SE von H eiligenblut, U fer der M öll W des Ortes, c. 1100 m, 8943/3, G rauerlenau, an A lnus incana, auf Physcia stellaris, 1987, J. H afellner [19846] & M . W alther (hb. H afellner). 5a. Arthonia destruens var. nana Grube & Hafellner var. nov. F ungus in thallo X anthoriae fallacis incolens. D iffert a varietate destruens apotheciis minoribus dispersisque et sporibus minoribus. T ypus: N epal, C entral H imalaya, T hak Khola (83)45*E, 28)45*N ), Jomoson C han N ordflanke, 3400 m, Astflechten an V iburnum, auf X anthoria fallax, 1986, G. & S . M iehe 16838 (G ZU –holotypus). Remarks: T his variety is distinguished from var. destruens by smaller (0·09– 0·17 mm diam.) and dispersed ascocarps as well as by smaller ascospores (10·5–13 #5–7 ìm). H itherto, it is known only from the type locality, where it occurs on X . fallax (H epp) Arnold. All other characters are similar to that found in var. destruens. A rthonia destruens var. nana is closely related to the type variety. H owever, we believe it is genetically distinct. M ature asci are already found in rather small ascomata and the spores in var. destruens are constantly larger. C ompared with lichenized species the parasitic representatives of the genus are quite monomorphic and therefore we consider the distinction of varieties in A . destruens the most appropriate solution. 6. Arthonia haem atostigm a Grube & Hafellner sp. nov. F ungus in thallo Ramalinae gracilis incolens. Apothecia minuta, sanguinea, circularia, sessilia, 0·09–0·17 mm diam.; in sectione 30–50 ìm alta. Epithecium hyalinum, 3–6 ìm altum, H ymenium hyalinum 17–25 ìm altum. H ypothecium hyalinum, 10–20 ìm altum. Omnes partes apotheciorum pigmento cristallino inspersae. Asci obovati, 15–18 #8–10 ìm magni, octospori, 1995 Lichenicolous A rthonia— Grube et al. 37 fissitunicati. Ascosporae hyalinae, 1-septatae, 6–8·5 #1·5–2·5 ìm. KOH grana cristallina colore violaceo solvuntur. T ypus: Brazil, São Paulo, Ilha C omprida gegenüber von C ananéia, in einem trockenen Stranddünenwald (Restinga), 2 m, auf Ramalina gracilis, 16 vii 1979, K . K alb (G ZU —holotypus) [as admixture in Kalb, Lich. neotr. 195: Ramalina gracilis, distributed as R. exiguella] (F ig. 4B) A scomata scattered, arising superficially, round, 0·09–0·17 mm diam., sessile, cushion-like, blood-red, with roughened surface, not diaphanous, in section 30–50 ìm tall. All parts densely interspersed with orange red, needleshaped, c. 2 #0·3 ìm crystals, the concentration decreasing downwards. Parathecioid layer indistinct. Epithecioid layer c. 3–6 ìm tall, composed of hyaline hyphae. Ascigerous layer 17–25 ìm tall. H ypothecioid layer with scattered orange-red needles, 10–20 ìm tall, sharply bordered below (hyphae very rarely penetrating the host cortex); composed of roundish (c. 3 ìm) to slightly elongated cells. Interascal filaments paraphysoidal, poorly branched and anastomosed, slightly protruding beyond the asci; cells sometimes knotted, 3–5 #1–2 ìm. A sci broadly obovate, 15–18 #8–10 ìm, with a short, inconspicous foot (3–5 ìm long), 8-spored, without I + or KI + tholus structures. A scospores narrowly obovate, persistently hyaline, without a perispore, 6–8·5 #1·5–2·5 ìm, 1-septate, not to slightly constricted; septum &median (F ig. 4B). V egetative hyphae&superficial, sometimes growing into the pseudocyphellae of the host lichen; cells 3–4 #2–3 ìm. Chemistry: Ascomatal gel I + orange-red; thallus hyphae KI + yellowish blue, epithecioid layer KI + yellowish blue, hypothecioid layer with KI + dirty bluish gel matrix; orange-red pigments K + turning violet and &dissolving (a fraction remains in the ascocarps). Life form: Lichenicolous, apparently not damaging the host; on Ramalina gracilis (Pers.) N yl. Remarks: T his species is known only from the type collection. It was found in dry coastal forests on sandy soil (restingas) where the host lichen grows in open situations. All other specimens of the exsiccate Kalb, Lich. N eotr. 195 were unsuccessfully checked for isotypes. 7. Arthonia m azosiicola Matzer & R. Santesson sp. nov. Ascomata in thallo specierum diversarum generis M az osia vigentes, gregaria ad confluentia, 0·05–0·4 #0·025–0·15 mm magna, rufofusca. Epithecium hyalinum ad luteolum, pro maxima parte gelatinosum. H ymenium in sectione 20–40 ìm altum, hyalinum ad flavum, hemiamyloideum. H ypothecium ochraceum. F ilamenta interascalia pauca, ramosa et anastomosantia, 1–3 ìm lata, Asci clavati, 20–35 #7–10 ìm magni, octospori, stipitati. Ascosporae primum hyalinae, in statu senescentiae fuscae, uniseptatae, 7–10 #2–3 ìm magnae. Substantia aurantiaca hypothecii K + violacea. T ypus: Java, T jibodas, primeval forest, on living leaves of Quercus, on M az osia phyllosema, vii 1898, E. N yman, E.L. 2a (U PS—holotypus). (F ig. 4C ) 38 T H E LIC H EN OLOG IST Vol. 27 A scomata crowded to aggregated and confluent, aggregates rounded or irregularly lobed, erumpent from the host thallus, rounded or elongated, simple or branched, 0·05–0·4 #0·025–0·15 mm (aggregates up to 1 mm), dark brownish red; in section 30–60 ìm tall. Parathecioid layer restricted to a few brown, slightly reticulate hyphae, cells c. 4–6 #1–3 ìm, hyphae covered by an orange to orange-red pigment. Epithecioid layer hyaline to yellowish, mainly gelatinous, with few hyphal elements, up to 13 ìm tall. Ascigerous layer hyaline to yellow, 20–40 ìm tall. H ypothecioid layer yellow, orange to brownish orange, up to 15 ìm tall; cells isodiametric to oblong. Interascal filaments paraphysoidal, scanty, branched and anastomosed, 1–3 ìm thick. A sci clavate, 20–35 #7–10 ìm, with distinct stipe, 8-spored; lacking I + and KI + structures in the tholus. A scospores oblong ovoid, hyaline, becoming brown when over-mature, not halonate, 7– 10 #(1·5–)2–3 ìm, 1-septate, not distinctly constricted at the septum (Fig. 4C ). V egetative hyphae indistinct. Chemistry: Ascigerous and hypothecioid layer I + deep red, KI + deep blue. Orange pigment turning violet and dissolving in K. Life form: Lichenicolous, apparently not damaging the host but ascomata often rather abundant; on M az osia phyllosema (N yl.) Zahlbr., M . rotula (M ont.) M assal., M az osia species. Remarks: A rthonia maz osiicola (as A . maz osiae) was first mentioned by Santesson (1952) but a valid description was not provided. A new specific epithet is selected for this species because A . maz osiae is regarded as a later homonym of A . maz osia (M assal. apud Krempelh.) Willey (as ‘A . maz oz ia’, Willey 1890: 40) according to IC BN Art. 64.3. T he fungus is wellcharacterized by dark reddish brown ascomata erupting from the host thallus and by small, 1-septate ascospores. So far the species is known from tropical America and the island of Java. S elected additional specimen examined: Costa Rica: C artago province, F lorencia S of the city of T urrialba, forest near to coffee plantations, c. 800 m, 09)53*N , 83)41*W, on M az osia rotula, 1991, M . M atz er [1532] & B. Pelz mann (U PS); ibid., on M az osia sp., 1991, M . M atz er [1531] & B. Pelz mann (G ZU ). 8. Arthonia neglectula Nyl. Flora 57: 13 (1874).—Conida neglectula (N yl.) Sacc. & D . Sacc., S yll. Fung. 18: 188 (1906); type: F inland, T avastia australis, Padosjoki, N yystölä, 1872, E. V ainio [on saxicolous, crustose, sterile, sorediate lichen, probably Lepraria neglecta] (H -N yl 4864!—holotype; U PS—isotype, not seen). non A rthonia neglectula sensu Almquist, see T riebel (1989: 55). (F ig. 4D ) A scomata arising superfically, scattered, &roundish, 0·09–0·2 mm diam., sessile, cushion-like, black (not translucent when moist), with rough surface, in section c. 70–80 ìm tall. Parathecioid layer formed by strongly carbonized hyphae, forming a transition from the hypothecioid layer to the epithecioid layer; texture as in epithecioid layer. Epithecioid layer strongly carbonized with dark brown pigments (K + olivaceous black), 5–15 ìm tall; cells c. 1995 Lichenicolous A rthonia— Grube et al. 39 4–5 ìm. Ascigerous layer hyaline to yellowish brown, sometimes with orange brownish clods, 20–30 ìm tall. H ypothecioid layer brown, 20–30 ìm tall; cells roundish, c. 3 ìm diam.; intercellular gels with clod-like brown pigments. Interascal filaments paraphysoidal, scanty and inconspicuous; cells 3–4 #0·5– 1 ìm. A sci clavate, 25–32 #11–15 ìm, with indistinct foot, 8-spored, I "; KI with inconspicuous, slightly elongated ring in the tholus. A scospores oblong ovoid, persistently hyaline, with faint gelatinous sheath (conspicuous in K), 7–10 #3–4 ìm, 1-septate, not or slightly constricted at the septum (Fig. 4D ). V egetative hyphae in the vicinity of lower sides of the ascocarps brown-walled; cells c. 6–8 #2·5–4 ìm. Chemistry: Ascomatal gel I + wine red, KI + bluish. Pigments in lower parts of the ascigerous layers K + turning lilac and dissolving. Life form: Lichenicolous, apparently not damaging the host; on sterile sorediose crust (cf. Lepraria neglecta). Remarks: T he species was included in T riebel (1989: 224) sub species exclusae. It was noted (T riebel 1989: 55, 56) that A . neglectula sensu Almquist belongs to A . almquistii Vainio. A . neglectula is known only from the type collection. 9. Arthonia pseudocyphellariae Wedin Lichenologist 25: 301 (1993); type: N ew Zealand, G isborne, U rewera N at. Park, Lake Waikaremoana, along N gamoko T rack, 38)46*S, 177)10*E, alt. c. 940 m, on thallus of Pseudocyphellaria multifida, 1992, W edin 4056 (U PS—holotype, not seen). (F ig. 2A) A scomata mostly crowded, developing in the uppermost cortex layers of the host, soon becoming erumpent, rounded or irregular, single to confluent, 0·1–0·35 mm diam., pale orange-red; in section 50–90 ìm tall. Parathecioid layer indistinct. Epithecioid layer yellowish to pale brownish, 5–15 ìm tall. Ascigerous layer yellowish, 30–40 ìm tall. H ypothecioid layer yellowish, 20–50 ìm tall, often with integrated remains of the host thallus. Interascal filaments paraphysoidal, scanty between the asci, branched and anastomosed, 1–1·5(–2) ìm wide. A sci clavate to broadly clavate, 30–40 #12–19 ìm, with distinct stipe, 8-spored, lacking I + and KI + structures in the tholus. A scospores oblong ovoid, hyaline at first, becoming brown and faintly warted when mature, 11·5–15 #4–6·5 ìm, often slightly constricted at the septum (when brown) (F ig. 2A). V egetative hyphae not distinct; mycelium more or less causing necrotic patches of up to 1 cm in diameter, without concentric zonation. Chemistry: All ascomatal parts I + reddish, KI + blue. Yellowish pigment in the ascomata K + strongly violaceous purplish and dissolving. Life form: Lichenicolous, apparently parasitic; on species of Pseudocyphellaria, e.g., P. glabra (J. D . H ook. & T aylor) D odge, P. homoeophylla (N yl.) D odge, and P. multifida (N yl.) D . J. G alloway & P. James (see Wedin 1993). 40 T H E LIC H EN OLOG IST Vol. 27 Remarks: T he species has many similarities with A . cinnabarinula and can be distinguished morphologically by the larger spores, the crowded ascomata and the necrotic patches. According to Wedin (1993), the species can be found in various types of forests in N ew Zealand, T asmania and South America, all of them with very moist conditions. T he hosts P. homoeophylla and P. glabra are closely related and form a species pair, whereas P. multifida is quite distinct (compare G alloway 1988). Another species of A rthonia growing on Pseudocyphellaria is A . pelvetii (H epp) Arnold, characterized by hyaline ascospores and by blackish brown ascomata that do not react with K. S pecimen examined: New Zealand: Wellington, T ongariro N ational Park, vicinity of Whakapapa Village, along Whakapapanui Stream, in N othofagus solandri v. cliffortioides dominated forest, 39)115*S, 175)32*E, 1050 m, on trunk of N othofagus, on Pseudocyphellaria glabra, 1990, M . W edin 2293 (G ZU ). 10. Arthonia tavaresii Grube & Hafellner sp. nov. F ungus in thallo Pyrenulae incolens. Ascomata erumpentia, asteroidea, c. 1–2·5 mm diam., pruina sanguinea obtecta, in sectione 150–200 ìm alta. Epithecium hyalinum, 20–30 ìm altum, obtectum pruina rubra. H ymenium hyalinum ad fuscidulum, 60–70 ìm altum. H ypothecium hyalinum ad pallidofuscum, 80–100 ìm altum. Asci clavati, 50–60 ìm magni, octospori, fissitunicati. Ascosporae infuscatae, 3-septatae, 17–23 #7–8 ìm, cellulis inaequalibus. KOH grana cristallina colore violaceo solvuntur. T ypus: C anary Islands, T enerife, M acizo de Anaga, M onte de las M ercedes, bei der Abzweigung nach El M oquinal N E ober Las M ercedes, c. 880 m, Lorbeerwald, an Stämmen von Laubbäumen, auf Pyrenula sp., 8 ii 1989, J. H afellner [23619] & A . H afellner (G ZU —holotypus) [Isotypes will be distributed in Santesson, Fungi lichenicoli exs.]. (F ig. 2B) A scomata scattered, crater-like erumpent, uplifting surrounding bark tissues and arising as astroid aggregates from below the bark surface (seen as brownish patches), composed of cross-divided branches with acute tips, the aggregates slightly convex, c. 1–2·5 mm large, with tips steeping into the bark; branch surface &flat, densely Bordeaux red pruinose, in section 150–200 ìm tall. Parathecioid layer poorly differentiated, composed of some brown-walled, conglutinate hyphae, which penetrate the adjacent bark tissues. Epithecioid layer overlaid by a 10–30-ìm tall zone formed by orange-red, clumped crystals, occasionally penetrated by hyphae; below a c. 20–30-ìm tall layer is formed by hyaline hyphae embedded in a &pale brownish gel; cells similar to that of interascal filaments. Ascigerous layer hyaline to pale brownish, 60–70 ìm tall. H ypothecioid layer hyaline to pale brownish, 80–100 ìm tall, with oblong cells (c. 5 #2 ìm; ascogenous cells 7 #3 ìm). Interascal filaments paraphysoidal, anastomosed, rarely branched; cells irregular in outline, sometimes slightly knotted and/or sinuous, 4–8 #1–2 ìm. A sci clavate, 50– 60 #16–20 ìm; foot inconspicuous (c. 10 ìm long); 8-spored, lacking I + and KI + structures in the tholus; sometimes with brownish tinged, compact plasma. A scospores obovate, with K + swollen gelatinous sheath around young spores, brown and minutely sculptured at maturity, 17–23 #7–8 ìm, 3-septate, not constricted at the septa when mature (when very old slightly constricted), septation proceeding downwards (Fig. 2B). V egetative hyphae indistinct. 1995 Lichenicolous A rthonia— Grube et al. 41 Chemistry: Interascal gel I + blue then slowly turning red; hypothecioid and epithecioid gel I + dark and dirty bluish red; ascomatal gel KI + bluish; orange-red pigments K + turning violet and dissolving at first, but then forming a granular dispersion. Life form: Lichenicolous, causing local damage around the ascomata; on Pyrenula sp. (‘A nthracothecium’) and Parmentaria chilensis Fée. Remarks: T he species is named in honour of the outstanding Portuguese lichenologist C . N . T avares. H is publications include major contributions to the lichen flora of M acaronesia. Although H arris (1989) synonymized Parmentaria with Pyrenula, the name Parmentaria chilensis has been picked up in Purvis et al. (1992). T he other host, above named Pyrenula sp., is similar to A nthracothecium libricolum (Fée) M üll. Arg. in the diagnostic characters but is clearly not identical to this species. T he spores of the host show distinct endospore thickenings and roundish cell lumina, which are characteristic for Pyrenula. C ited as A . libricolum, this host is the only ‘A nthracothecium’ species known from the C anary Islands. A dditional specimens examined: Azores: Pico: 9 km SE of S. Roque do Pico, M istério da Prainha, alt. c. 570 m, [site 22], on Parmentaria chilensis, 1992, O. W . Purvis & P. W . James (hb. Purvis); 8·5 km SSE of S. Roque do Pico, M istério da Prainha, alt c. 480 m, [site 19], on Laurus az orica, on Pyrenula sp., 1992, O. W . Purvis & P. W . James (BM ).—Canary Islands: T enerife, M acizo de Anaga, an der Straße zum C abezo del T ejo c. 2 km N W der Abzweigung von der Straße nach C hamorga, c. 870 m, Lorbeerwald, an Laurus az orica, auf Pyrenula 1989, J. H afellner [30732] & A . H afellner (G ZU ). We are grateful to the curators of BM , G , H , S, U PS, to R. Lücking and to O. W. Purvis for the loan of specimens and to J. Elix for linguistic improvement of the English text. M ats Wedin is acknowledged for providing unpublished data. T his project was partly supported by F onds zur F ördenung der wissenschaftlichen F orschung (Projekt P 9588-BIO) to J. H afellner. R  Alstrup, V. & H awksworth, D . L. (1990) T he lichenicolous fungi of G reenland. M eddelelser om Grønland, Bioscience 31: 1–90. C lauzade, G ., D iederich, P. & Roux, C . (1989) N elikeniĝintaj F ungoj Likenloĝaj. Bulletin de la S ociété linnéenne de Provence. N uméro spécial 1: 1–142. C oppins, B. J. (1992) A rthonia Ach. In: T he Lichen flora of Great Britain and Ireland (O. W. Purvis, B. J. C oppins, D . L. H awksworth, P. W. James & D . M . M oore, eds): 74–88. London: N atural H istory M useum Publications. G alloway, D . J. (1988) Studies in Pseudocyphellaria (lichens) I. T he N ew Zealand species. Bulletin of the British M useum ( N atural H istory) , Botany series 17: 1–267. G rube, M . (1991) Studien an rotfrüchtigen A rthonia-Arten. In: 6. Österr. Botanikertreffen, K urz f. Beitr. (J. H afellner, H sg.): 56. G raz. H arris, R. C . (1989) A sketch of the family Pyrenulaceae (M elanommatales) in Eastern N orth America. M emoirs of the N ew Y ork Botanical Garden 49: 74–107. H awksworth, D . L. (1991) Charcotia H ue, and A rthonia species lichenicolous on Umbilicaria. S ystema A scomycetum 10: 127–134. M üller Argoviensis (‘M üller’), J. (1881) Lichenologische Beiträge XIII. Flora 64: 225–236. Purvis, O. W., C oppins, B. J., H awksworth, D . L., James, P. W. & M oore, D . M . (1992) T he Lichen Flora of Great Britain and Ireland. London: N atural H istory M useum Publications. Redinger, K. (1937) Arthoniaceae. Rabenhorst’s K ryptogamen-Flora 9, 2, 1: 1–180. Rehm, H . (1900) Beiträge zur Pilzflora von Südamerika. VII. D iscomycetes. H edwigia 39: 80–99. Santesson, R. (1952) F oliicolous Lichens I. A revision of the taxonomy of the obligately foliicolous, lichenized fungi. S ymbolae Botanicae Upsalienses 12(1): 1–590. 42 T H E LIC H EN OLOG IST Vol. 27 Santesson, R. (1960) Lichenicolous fungi from northern Spain. S vensk Botanisk T idskrift 54: 499–522. T riebel, D . (1989) Lecideicole Ascomyceten. Eine Revision der obligat lichenicolen Ascomyceten auf lecideoiden F lechten. Bibliotheca Lichenologica 35: 1–278. Wedin, M . (1993) A rthonia pseudocyphellariae, a new lichenicolous fungus from the Southern H emisphere. Lichenologist 25: 301–303. Willey, H . (1980) A synopsis of the genus Arthonia. N ew Bedford: privately published. A ccepted for publication 12 December 1993