Smithsonian National Museum of Natural History

Website Search Box

Department ofBotany

by Harrie Sipman, Botanical Museum Berlin-Dahlem

Revised June 1996

The key deals with c. 190 genera known from or expected in the three Guianas (Guyana, Surinam, French Guiana). Included are all genera known from literature or from recent, unpublished collections. Genera in " " concern provisional identifications or taxa of uncertain or provisional taxonomic position. Genera in [ ] are known from surrounding areas and expected for the Guianas.

The genera Cladia, Cladina, and Cladonia may now be keyed to species using the Key to the Cladoniaceae of the Guianas, by Ted Ahti and Harrie Sipman, 1997.

Basic knowledge of lichens is required for use of the key. For easier use a simplified terminology is applied. e.g., all interascal filaments are called paraphyses.

Although the key is principally meant for the Guianas, it is likely to be of use throughout the Amazon basin, and genera recorded from that area are included as much as possible.

N.B. The number series of the couplets is incompletely used, because numbers are reserved for future extensions. Interrupted sites are marked by three blank lines.

The following persons are gratefully acknowledged for contributions: R. C. Harris (1986), L. Brako (1986) , J. Knoph (1986), A. Aptroot (1996). Errors are my own responsibility!

Additions, corrections, recommendations are very welcome! Please contact Harrie Sipman, who would appreciate such cooperation very much. E-mail: Please address inquiries about the presentation of this key and about the Smithsoniam Institution's Biological Diversity of the Guianas Program to Sara Alexander by E-mail:

la   Thallus fruticose, i.e. with free-standing or hanging, 
     terete or flattened, often branched lobes, which may measure a few 
     mm to several dm in length, and which are affixed only at their 
     base, rather uniformly colored on all sides; in addition, 
     squamulose or crustose thallus may be present                      2
 b   Thallus foliose, i.e. forming a flat plate, measuring 
     usually several cm in diam., more or less deeply divided into lobes, 
     which grow usually parallel to their substrate, usually rather 
     closely appressed to it, often attached by tomentum or rhizines 
     on the lower side, so that the whole thallus can usually be lifted 
     off easily; the lower side mostly differing markedly in color 
     from the upper side, often brownish or black                      20
 c   Thallus squamulose, i.e. at first sight seeming crust-
     like, but composed of flat, generally separate lobes, rarely 
     exceeding 1-2 mm in length, which grow more or less parallel to the 
     substrate, attached to it by their base or by their underside, not 
     by rhizines, so that the thallus cannot be lifted off without 
     breaking into separate lobes; their lower side usually differing 
     markedly in color from the lower side, often whitish              80
 d   Thallus crustose, i.e. forming a layer which covers the 
     substrate and is affixed to it with its whole lower side, in such 
     a way that it cannot be lifted off, sometimes penetrating into 
     the substrate or even developed inside the substrate (e.g. 
     endophloeodic: growing inside the (outer) bark cells)            100

2a (fruticose)  Thallus branches with central cavity                    3
 b   Thallus branches solid, with arachnoid or more compact 
     central tissue                                                     8

3a   Thallus surface glossy, pale brown to brown, with 
     usually frequent perforations; terrestrial, occasionally on 
     mossy tree trunks                                             Cladia
 b   Thallus surface dull, usually whitish, greenish or 
     greyish; perforations in most species absent, in some species 
     present in axils of ramifications (rarely more frequent, than 
     thallus yellowish)                                                 4

4a   Thallus branches with squamules, especially at the base     Cladonia
 b   Thallus without such appendages                                    5

5a   Rare epiphytic species, known only from Mt. Roraima at 
     c. 2000 m (widespread and common in the Andes)              Oropogon
 b   Widespread terrestrial species, mostly on white sand, 
     occasionally on decaying tree stumps                               6

6a   Thallus surface slightly felty, without cortex (Cladonia 
     signata would also key out here)                             Cladina
 b   Thallus surface smooth, with thin cortex                    Cladonia

8a   Thallus branches with tough central stand, which becomes 
     visible between the breaking outer layer by moderate tension   Usnea
 b   Thallus branches without tough central strand, breaking 
     completely by tension                                              9

9a   Epiphytic species, occasionally on decorticated wood              10
 b   Saxicolous species, occasionally on thin soil cover on rock       15

10a  Lobes applanate, over two times wider than thick                  11
  b  Lobes more or less terete                                         12

11a  Thallus greenish grey, over 2 cm long when full-grown, 
     often pendant                                               Ramalina
  b  Thallus whitish, c. 1 cm long when full-grown, erect         Siphula

12a  Thallus, at least in part, yellow, reaction K+ purple  
  b  Thallus bluish grey or greenish to whitish yellow, K-             13

13a  Thallus bluish grey to black, basal branches sometimes 
     whitish; branches more or less terete; with bluegreen algae       14
  c  Thallus whitish yellow; branches flattened, composed of 
     chains of apothecia; with green algae                     Polystroma

14a  Richly branched; main branches over 0.1 mm wide, with more 
     or less scattered tomentum; no apothecia; with multilayered 
     cortex; algae Nostoc in glomerules, not gelatinous   Dendriscocaulon
  b  Richly branched; main branches up to 0.1 mm wide, without 
     tomentum; apothecia common (upland); cortex composed of 
     a single cellular layer; algae Scytonema, gelatinous     Polychidium
  c  Sparingly branched; main branches over 0.1 mm wide, 
     without tomentum; apothecia common; no cellular cortex; 
     algae Nostoc in chains, gelatinous                       Lempholemma

15a  Fruticose thallus with granular or squamulose 
     appendages; with green algae                            Stereocaulon
  b  Fruticose thallus without such appendages; algae 
     bluegreen or green                                                16

16a  On rock; thallus composed of brownish to blackish, 
     fruticose parts only; ascomycetes, though rarely fruiting         17
  c  On soil; fruticose thallus yellowish, without algae; in 
     addition, crustose, algiferous, dark green thallus 
     present; basidiomycete                                  Multiclavula

17a  On temporarily submersed rocks in streams; thallus 
     gelatinous, black; rare species                                   18
  b  On mostly dry rock faces on land; thallus not 
     gelatinous, white or grey; common species                         19

18a  Lobes flat, little branched, over 1 cm long                 Jenmania
  b  Lobes rounded and richly branched, forming cushions 
     less than 1 cm thick                                        Lichina?

19a  Thallus dark brown to black; algae 
     bluegreen; on granite                                        Peltula
  b  Thallus white to pale grey; algae green; on sandstone 
     (cf. also Toninia, with thallus composed of rounded, sometimes 
     rather elongated, warts; recognizable by dark grey color 
     and frequent presence of apothecia)                          Siphula

20a (1, foliose)  Lobes with thread-like 
     appendages (rhizines) on lower side; algae green                  21
  b  Lobes with tomentum on lower side, at least on part of 
     it; algae mostly bluegreen                                        41
  c  Lobes with naked lower side; algae various                        61

21a  Thread-like appendages on the margins of the lobes 
     (cilia), sometimes also on underside (rhizines)                   22
  b  Thread-like appendages not on the margins of the lobes, 
     only on underside (rhizines)                                      31

22a  Cilia with inflated base                                          23
  b  Cilia without inflated base                                       24

23a  Upper side of thallus yellowish green, usnic acid 
     present                                                     Relicina
  b  Upper side of thallus whitish grey, atranorin present     Bulbothrix

24a  Rhizines white or grey, sometimes black, but then 
     usually with perpendicular side branchlets; lower side 
     often without cortex, felty; spores biloculate, dark    Heterodermia
  b  Rhizines black; lower side always with cortex, smooth; 
     spores uniloculate, colorless                                     25

25a  Rhizines one or more times dichotomously branched       Hypotrachyna
  b  Rhizines mostly unbranched, or in part irregularly branched       26

26a  Thallus lobes elongate, mostly under 2 mm wide         Parmelinopsis
  b  Thallus lobes short and wide, mostly over 5 mm wide               27

27a  Underside near lobe tips without rhizines, naked in a 
     several mm wide zone                                      Parmotrema
  b  Underside rhizinate to the margin                                 28

28a  Underside near margin brown, with scattered rhizines of 
     variable length                                              Rimelia
  b  Underside near margin pale, with dense, short rhizines 
     mixed with scattered longer ones (not yet known from the Guianas)  
31a  Rhizines absent from marginal zone; 
     thallus lobes wide, often over 10 mm wide                 Parmotrema
  b  Rhizines present till lobe margins; thallus lobes 
     usually up to 2 mm wide, rather narrow and deeply dissected       32

32a  Rhizines frequently dichotomously branched              Hypotrachyna
  b  Rhizines mostly unbranched or a few times irregularly 
     branched                                                          33

33a  Apothecia completely black, without grey thalline 
     margin when well developed                                    Pyxine
  b  Apothecia with grey thalline margin                               34

34a  Spores biloculate, grey to brown; lower side whitish or 
     black, sometimes without cortex                                   35
  b  Spores uniloculate, hyaline; lower side brown to black, 
     always with cortex                                                37

35a  Thallus applanate; cortex composed of periclinally 
     arranged hyphae                                                   36
  b  Thallus more or less ascendant; cortex composed of 
     longitudinally arranged hyphae, surface slightly 
     longitudinally striate                                  Heterodermia

36a  Apothecia with pale hypothecium; thallus without 
     divaricatic acid, with dull, black or pale, lower cortex     Physcia
  b  Apothecia with dark hypothecium; thallus of Guianan 
     species always with divaricatic acid, with glossy, black 
     lower cortex                                               Dirinaria

37a  Epiphytic or epilithic; thallus 
     whitish grey, without usnic acid                                  38
  b  Epilithic; thallus yellowish green, with usnic acid   Xanthoparmelia

38a  Lower surface pale brown to brown; spores less than 
     10 µm long                                            Pseudoparmelia
  b  Lower surface dark brown to black; spores over 10 
     µm long                                                 Canoparmelia

41a  Thalli with small, rarely over 5 mm 
     wide, lobes, usually closely appressed; algae always bluegreen    42
  b  Thalli with usually large, over 5 mm wide lobes, not or 
     loosely appressed; algae bluegreen or green                       46

42a  Upper surface tomentose; tomentum on lower side often 
     restricted to marginal patches; uncommon                   Erioderma
  b  Upper surface glabrous; tomentum on lower side usually 
     spread over most of the thallus                                   43

43a  Cortex composed of longitudinally arranged hyphae; thallus 
     often with concentric ridges; apothecia without thalline 
     margin                                                   Coccocarpia
  b  Cortex not composed of longitudinally arranged hyphae; 
     thalli without concentric ridges                                  44

44a  Thallus closely appressed to substrate                            45
  b  Thallus loosely appressed with ascending margins; 
     uncommon                                                   Leioderma

45a  Thallus without distinct prothallus; apothecia always 
     with thalline margin                                        Pannaria
  b  Thallus with distinct, often tomentose, prothallus; 
     apothecia with or without thalline margin                Parmeliella

46a  Thallus with small, sharply delimited, raised or 
     immersed  white or yellow, tomentum-free spots on lower side      47
  b  Thallus with larger, not sharply delimited, pale, 
     tomentum-free areas on lower side                            Lobaria

47a  White spots on lower side, with prominent, raised 
     margin (cyphellae)                                            Sticta
  b  Yellow spots on lower side, with margin hardly 
     raised above the center (pseudocyphellae)          Pseudocyphellaria

61a  Thallus of felty structure                                        62
  b  Thallus compact, usually with differentiated cortical 
     layer                                                             63
62a  With bluegreen algae, without ascocarps (basidiolichen); 
     thallus usually growing parallel to substrate  
  b  With Trentepohlia algae, apothecia sometimes
     present; thallus often growing at right angles to 
     substrate                                                Coenogonium

63a  Thallus scarcely dissected, lobes + 
     hemispherical; basidiolichens without ascocarps                   64
  b  Thallus strongly dissected, lobes usually much longer 
     than wide; apothecia often present                                65

64a  Thallus concentrically ridged, with bluish color          Dictyonema
  b  Thallus smooth with raised margin, with dark greenish        Corella

65a  Thallus bluegrey to black, gelatinous; 
     algae Nostoc in chains; no cellular cortical layer           Collema
  b  Thallus bluegrey to black, gelatinous; algae Nostoc in 
     chains; cortical layer one cell thick                             66
  c  Thallus whitish grey to greenish grey, not gelatinous; 
     algae green; cortex well developed, several cells thick           67

66a  Spores septate; thallus often under 0.5 mm thick           Leptogium
  b  Spores simple; thallus over 0.5 mm thick                      Physma

67a  Spores dark, biloculate and ovate; underside black, with cortex 
  b  Spores colorless, pluriloculate and bacillar; underside 
     white, without cortex                                      Physcidia

68a  Apothecia, at least when well developed, without 
     thalline margin                                               Pyxine
  b  Apothecia with persistent thalline margin                         69

69a  Apothecia with dark hypothecium; thallus lobes elongate 
     and laterally confluent                                    Dirinaria
  b  Apothecia with pale hypothecium; thallus lobes not 
     laterally confluent                                     Hyperphyscia

80a (1, squamulose)  Perithecia present; spores 
     muriform; algae present in hymenium                       Endocarpon
  b  Perithecia (rarely) present; spores transversely 
     septate: no algae in hymenium                             Normandina
  c  Apothecia present, or fruitbodies absent                          81

81a  Squamules + rounded, whitish with raised margin, ca. 
     1 mm diam.; fruitbodies unknown (parasitic (?) perithecia 
     sometimes present; spores transversely septate; no algae 
     in hymenium)                                              Normandina
  b  Squamules usually elongated and greenish, without raised margin   82

82a  Squamules on a felty layer of hyphae (prothallus)                 83
  b  Squamules directly on substrate, sometimes with prothallus 
     penetrating into the substrate, but not forming a layer 
     over the substrate                                                91

83a  Algae bluegreen                                                   84
  b  Algae green                                                       85

84a  Thallus without prothallus; apothecia always with 
     thalline margin                                             Pannaria
  b  Thallus with distinct, often tomentose, prothallus; 
     apothecia with or without thalline margin                Parmeliella

85a  Hymenium IKI+ orange                                 [Opegraphaceae]
     (probably undescribed genus, known so far from Neblina, Venezuela)
  b  Hymenium IKI+ blue                                                86

86a  Upper surface of squamules byssoid, lacking cortex and 
     woolly by free hyphae                                       Crocynia
  b  Upper surface of squamules more or less smooth, 
     sometimes pruinose, cortex present                                87

87a  Squamules with an upper and lower cortex comprised of a 
     thin layer of cubic cells                               Eschatogonia
  b  Squamule cortex otherwise, lower cortex usually absent            88

88a  Spores generally over 25 µm, transversely multiseptate   Squamacidia
  b  Spores generally under 25µm, 1-2-loculate                Phyllopsora

91a  Algae bluegreen                                              Peltula
  b  Algae green                                                       92

92a  Squamules greenish above, whitish below, usually 
     elongate (primary thallus squamules of Cladonia may key 
     out here)                                                  "Biatora"
  b  Squamules whitish grey on both sides, elongate and 
     erect                                                        Siphula
  c  Squamules whitish grey on both sides, usually roundish            93

93a  Apothecia stalked and raised above the squamules, 
     usually on branched pseudopodetia                       Stereocaulon
  b  Apothecia sessile between the squamules                Toninia(s.l.)

100a (1, crustose)  Foliicolous species, found on living leaves  
   b Corticolous, terrestrial or saxicolous species                   200

101a (foliicolous)  Thallus with dish-like, 
     stalked isidia; ascocarps unknown              Porina (Phyllophiale)
  b Thallus naked or with somewhat hair-like hypophores 
     with flattened tips, producing conidia                           102
   c Thallus with c. 0.1-2 mm long, sterile bristles/hairs            170

102a Apothecia present, rounded                                       103
   b Lirellae present, elongate with black, distinctly 
     carbonaceous labiae                                        Opegrapha
   c Perithecia present                                               150
   d Ascocarps absent, but conidangia present                         180
   e Black-rimmed goniocystangia resembling 
     ascocarps, but producing goniocysts, present Opegrapha gr. lambinoni

103a Ascocarps (seemingly) without excipular tissue, 
     without visible margin                                           104
   b Ascocarps with clearly differentiated margin                     110

104a  Fruitbodies white, with asci scattered in loose, 
     hyphal tissue; spores muriform                                   105
   b Fruitbodies usually colored, compact, with asci in 
     distinct, gelatinous hymenium                                    106

105a Spores muriform                                         Cryptothecia
   b Spores transversely septate only                           Stirtonia

106a Paraphyses straight; spores transversely 
     septate; asci with I+ blue tholi; hymenium I+ blue      Byssolecania
   b Paraphyses branched and anastomosing; asci with I-
     negative tholi; hymenium I+ red or blue                          107
   c Paraphyses branched and anastomosing; asci with I-
     negative tholi; hymenium I-negative                              110

107a Spores transversely septate                                      108
   b Spores muriform                                         Arthothelium

108a Conidia filiform, over 50 µ m long, produced in 
     elongate pycnidia with lateral pore                    Eremothecella
   b Conidia bacillar, under 20 µ m long, produced in 
     rounded pycnidia with apical pore                           Arthonia

110a Apothecia immersed in the thallus, disc 
     level with thallus surface, sometimes surrounded by a raised 
     thalloid margin                                                  111
   b Apothecia adnate to sessile, often constricted at the 
     base; disc above thallus surface                                 115

111a Thallus with cortical layer of quadratic, rectangular 
     or rounded cells, one cell-layer thick                           112
   b Thallus without cortical layer or with a cartilaginous 
     cortical layer                                                   113

112a Spores transversely septate; epithecial algae absent   Asterothyrium
   b Spores muriform; epithecial algae present               Gyalectidium

113a Paraphyses simple; with splitting, 
     erect or recurved, thalline margin                       Chroodiscus
   b Paraphyses branched and anastomosing; without thalline margin    114

114a Spores bicellular; hyphophores stalked                   Echinoplaca
   b Spores at least 3-septate; hyphophores without stalk, 
     consisting of a sessile, gelatinous ball                 Actinoplaca

115a Hymenium I+ blue, at least near the asci; asci 
     I+ blue, usually in the tholus, at least along the outside       116
   b Hymenium I+ reddish; asci I-negative                         Mazosia
   c Hymenium and asci I-negative or very pale blue                   135

116a Spores simple                                                    117
   b Spores transversely septate only                                 118
   c Spores muriform                                                  126

117a Thallus smooth, containing green algae; apothecia 
     with pronounced margin                         "Lecidea" gr. piperis
   b Thallus granular, containing bluegreen algae; 
     apothecia soon convex and immarginate           "aff. Leprocollema?"

118a Excipulum formed externally by loose, felty hyphae, 
     which surround the apothecia as a thin circle              Byssoloma
   b Excipulum compact, also externally                               119

119a Asci with a I+ blue tubular structure in the tholus              120
   b Asci without tubular structure, with or without a I+ 
     blue axial mass                                                  121

120a Apothecia usually over 0.5 mm wide, flat; I-positive 
     tubular structure in ascus apex distinctly stained over its 
     whole length; excipulum usually filled with crystals         Badimia
   b Apothecia mostly under 0.5 mm side, soon convex; I-positive 
     tubular structure in ascus apex most distinctly stained 
     in its basal part; excipulum not filled with crystals     Fellhanera

121a Campylidia never present; asci with 
     conical or rounded, I+ pale blue axial mass                      122
   b Campylidia (usually) present; asci without I+ pale 
     blue axial mass                                                  123

122a Asci with conical axial mass; excipulum 
     prosoplectenchymatic                                         Bacidia
   b Asci with rounded axial mass; excipulum 
     paraplectenchymatic                         Woessia (incl. Bacidina)

123a Hypothecium purplish; apothecia 
     black, sometimes with white pruina                        Tapellaria
   b Hypothecium usually not purplish; apothecia variously colored    124

124a Ascospores 3-septate, fusiform                                   125
   b Ascospores 7-septate, bacillar; campylidia as in 
     Calopadia                                           "Tapellariopsis"
   c Ascospores multiseptate, over 10-septate, acicular; 
     no campylidia                                              Bapalmuia

125a Campylidia producing flask-shaped, c 20 µm long conidia     
   b Campylidia producing ovoid, c. 10 µm long conidia          Loflammia

126a Margin of apothecium with long, stiff hairs               
   b Margin of apothecium without such hairs                          127

127a Epithecial algae present                                 Sporopodium
   b Epithecial algae absent                                          128

128a Apothecia black, sometimes with white pruina, with 
     flat disc; hypothecium purplish                           Tapellaria
   b Apothecia dark brown, with flat disc                       Calopadia
   c Apothecia red to carmine, with flat disc                   Loflammia
   d Apothecia yellowish, soon convex                            Logilvia

135a Apothecia elongate to angular or round, not 
     constricted at base, margin formed by a dark tissue which 
     originally covers the disc                                  Aulaxina
   b Apothecia round to slightly irregular, margin not 
     formed by a dark tissue which originally covers the disc         136

136a Apothecia proliferating on their margins; mainly on 
     leaf margins                                              Polystroma
   b Apothecia not proliferating on their margins                     137

137a Paraphyses simple, straight                                      138
   b Paraphyses branched and anastomosing                             139

138a Apothecia yellow; spores bicellular in cylindrical asci 
     (NB: for species determination it is important to look for 
     the pyncidia, which are often found on separate plants)    Dimerella
   b Apothecia variously colored; spores variously septate 
     in clavate asci                                             Gyalidea

139a Excipulum thinly spreading laterally 
     over the thallus                                         Echinoplaca
   b  Excipulum not spreading, forming a prominent margin             140

140a Without bristle-like hyphophores                        Gyalideopsis
   b With bristle-like hyphophores                            Actinoplaca

150a Thallus subcuticular, very glossy 
     (incl. Phylloporis, Raciborskiella)                         Strigula
   b Thallus epicuticular, forming a usually dull sheet 
     over the cuticula of the leaf                                    151

151a Perithecia smooth                                                154
   b Perithecia with warts, bristles or a disc-like expansion 
     around the pore; spores transversely septate or muriform         152

152a Perithecia whitish, with a disc-like extension around 
     the pore or with more scattered scales                 Aspidothelium
                                                 (included in Thelenella)
   b Perithecia reddish or black, with bristle-like 
     extensions, usually in a whirl around the pore                   153
153a Asci bitunicate; spores 14-17 x 3-4 µm, 3-septate            Lyromma
   b Asci thinwalled; spores usually over 18 µm long               Porina

154a Spores pale grey-brown, transversely 3-septate      
   b Spores colorless, transversely septate or muriform               155

155a Spores two-celled                                                156
   b Spores transversely pluriseptate                                 157
   c Spores muriform                                                  158

156a Spores under 30 µm long                                Anisomeridium
   b Spores over 50 µm long                                    Musaespora

157a Ascocarps solitary                                            Porina
   b Ascocarps grouped in raised thallus parts           "Flavobathelium"

158a Perithecia with outer wall containing dark-
     brown pulveraceous masses, often irregularly shaped  Phyllobathelium
   b Perithecia with outer wall without such masses, regular          159

159a Spores lumbricoid, with few longitudinal cells         Phylloblastia
   b Spores oval, with numerous longitudinal cells             Thelenella

170(101) (Sterile, hairy plants cannot be identified 
     with certainty; they are arranged artificially under 
     Tricharia melanothrix Fée, with black hairs, and T. 
     leucothrix Fée, with white hairs)
   a Apothecia immersed, disc level with thallus surface, 
     sometimes surrounded by a raised, rim-like thallus area          171
   b Apothecia sessile, often constricted at the base                 178

171a Hairs white. often over 1 mm long                                172
   b Hairs brown to black, short, under 0.2 mm                        177

172a Perithecia present; hairs tiny, on the perithecia             Porina
   b Apothecia present; hairs mostly on the thallus                   173

173a Hairs tiny, dense, forming tomentose areas on the 
     thallus and thalloid apothecial margins                      Mazosia
   b Hairs larger, often over 1 mm long, bristle-like                 174

174a Thallus with cortical layer of quadratic, rectangular 
     or rounded cells, one cell-layer thick                           175
   b Thallus without cortical layer or with a cartilaginous 
     cortical layer                                                   176

175a Spores transversely septate; epithecial algae absent   Asterothyrium
   b Spores muriform; epithecial algae present               Gyalectidium

176a Ascocarps surrounded by a raised thalloid rim               
   b Ascocarps without raised thalloid rim, with a more or 
     less distinct excipulum                                  Echinoplaca

177a Ascocarps without black proper margin                   
   b Ascocarps with black proper margin                          Aulaxina

178a Excipulum laterally spreading over the thallus, 
     thus apothecia seemingly immarginate                     Echinoplaca
   b Excipulum not laterally spreading, apothecia 
     distinctly marginate                                       Tricharia

180a campylidia present: greyish or yellowish ear-like 
     structures which are strongly raised on one side, and 
     produce conidia: various species of Badimia, Loflammia, 
     Sporopodium, not identifiable without apothecia; 
     artificially arranged in the genus Pyrenotrichum                 181
   b hygrophores or other brush-like conidiogenous structures         186
   c immersed or slightly exserted conidangia, black or 
     concolorous with thallus                                         188

181a Campylidia producing ovoid, pyriform, simple or 
     uniseptate conidia                                               182
   b Campylidia producing flask-shaped, non-septate 
     conidia                                                      Barubia
   c Campylidia producing filiform, septate, sometimes 
     branched conidia                                                 184
182a Campylidia producing uniseptate conidia with unequal 
     cells; usually found with ascomata                         Byssoloma
   b Campylidia producing simple conidia                              183

183a Campylidia short, on top of a thalloid cylinder; 
     algae between the conidiophores                          Sporopodium
   b Campylidia not on thalloid cylinder; no algae between 
     the conidiophores (Loflammia and Logilvia have similar 
     campylidia, but are unlikely to be found without ascomata)  

184a Campylidia with branched, somewhat star-shaped conidia    
   b  Campylidia with unbranched conidia                              185

185a Campylidia with cylindrical, to c. 40 µm long 
     conidia without appendages                                  Arthonia
   b Campylidia with cylindrical, c. 100 µm long 
     conidia with appendages                                      Badimia
   c Campylidia with tapering, c. 50 µm long conidia without 
     appendages (genera to be separated by ascoma characters) 

186a True hyphophores present, producing conidia 
     in a free-hanging gelatinous ball                        Echinoplaca
   b Conidia not produced in a free-hanging gelatinous 
     ball, but in a conidangium inside the brush-like structure       187

187a Conidangia brown to black, star-like branched; on leaf 
     upper surface                                                Lyromma
   b Conidangia pale brown, simple; on leaf margin                Woessia

188a Conidangia black                                                 189
   b Conidangia pale, inconspicuous                             Dimerella

189a Conidia simple                                         Anisomeridium
   b Conidia septate                                                  190

190a Conidangia separate                                         Strigula
   b Conidangia in groups of c. 10-30 in elevated 
     thallus areas                                        Phyllobathelium

200a (100, crustose, non-foliicolous lichens) Ascocarps present      
   b Ascocarps and conidangia absent; usually sterile crustose 
     lichens; only a selection of common and characteristic 
     species treated                                                  401
   c Ascocarps absent, conidangia present                             450

201a Ascocarps rounded, with open disc (apothecia), 
     immersed, sessile or stalked                                     202
   b Ascocarps closed, with porus (perithecia), immersed or 
     sessile                                                          300
   c Ascocarps elongate, with open or slit-like disc 
     (lirellae), immersed or sessile                                  350

202a Apothecia covered by powdery, staining masses of spores 
     ripening in a layer above the asci (mazaedia); apothecia 
     sessile or sometimes on long, thin stalks (Caliciales)           203
   b Apothecia not covered by spore masses, not staining, 
     releasing spores from each ascus separately, immersed or sessile, 
     rarely stalked                                                   210

203a Apothecia pin-shaped, with up to 2 mm long, thin 
     stalk; spores simple, pale brown                                 204
   b Apothecia sessile                                                205

204a Apothecia black; spores two-celled, dark brown              Calicium
   b Apothecia brownish; spores simple, pale brown  

205a Apothecia without thalline margin                                206
   b Apothecia with thalline margin                                   207

206a Spores two-celled                                          Pyrgidium
   b Spores four-celled                                         Pyrgillus

207a Spores two-celled                                        
   b Spores four-celled                                     Schistophoron
210a Hymenium I+ blue, at least near asci; asci I+ blue, 
     at least along their outside, and usually also in their tips; 
     paraphyses usually straight and unbranched, except near the 
     tips, rarely branched and anastomosing; spores simple or 
     variously septate, with rather equal cells (Lecanorales)         211
   b Hymenium I+ red or blue; asci I-negative, except 
     sometimes for a small, I+ blue ring around the ocular chamber; 
     paraphyses densely branched and anastomosing; spores variously-
     septate but not simple, often with a single, much larger cell 
     terminally or (sub)medially (Opegraphales, Arthoniales)  
   c Hymenium I-negative, rarely pale blue; asci I-negative 
     or very pale blue throughout; paraphyses straight and unbranched, 
     except sometimes near the tips, rarely branched and anastomosing; 
     spores variously septate but not simple, with rather equal cells 
     (terminal spore parts may still lack septation in young spores) 
     (Gyalectales, Graphidales)                                       280

211a Spores grey to brown, at least when old, usually bicellular      212
   b Spores persistently hyaline, various                             214

212a Spore septa thin, lumina cubical; pycnidia bacillar, 
     up to 5.5 µm long                                            Buellia
   b Idem; pycnoconidia filiform, curved, up to 30 µm long    [Amandinea]
   c Spore septa thickened, lumina rounded or more complicated        213

213a Apothecial margin without algae, concolorous with the 
     disc; spores with thin-walled, rather pointed poles         Hafellia
   b Apothecial margin with algae, usually concolorous with 
     thallus; spores usually with thickened polar walls, not pointed  

214a Spores simple                                                    215
   b Spores transversely septate only                                 230
   c Spores muriform                                                  250

215a Apothecial margin lecanorine, of same color as 
     thallus, with algal layer                                        216
   b Apothecial margin lecideine or biatorine, of same 
     color as disc, without algal layer, or apothecia without 
     distinct margin                                                  220

216a Spores under 20 µm long                                          217
   b Spores over 30 µm long                                           218

217a Spores 8/ascus                                              Lecanora
   b Spores many/ascus                                           Maronina

218a Disc often punctiform, ascocarps often in compound 
     groups immersed in warts; spores thick-walled and 
     generally over 50 µm long                                 Pertusaria
   b Disc open, apothecia separate; spores under 50 µm long   Ochrolechia

220a Apothecial disc bright red, K+ purplish                 
   b Apothecial disc not bright red, usually brown or 
     black, K-                                                        221

221a Spores more than 16 per ascus, small and globose  
   b Spores fewer than 16 per ascus, never globose                    222

222a Paraphyses anastomosing; exciple absent or indistinct; 
     apothecia soon convex and globular                         [Micarea]
   b Paraphyses not anastomosing; exciple present, usually 
     obvious in young apothecia at least; apothecia often flat        223

223a Algae bluegreen; thallus slightly gelatinous; on 
     periodically inundated rock                            "Psorotichia"
   b Algae green; thallus not gelatinous; substrate various           224

224a Asci with strongly I+ blue tholus, in which a paler 
     axial mass may be present                                        225
   b Asci with weakly I+ blue tholus, in which an 
     I+ blue central tube may be present            "Lecidea" gr. piperis

225a Apothecia dark brown to black; thallus whitish or greenish, 
     often K+ yellow or C+ orange; mostly on tree bark        [Lecidella]
   b Apothecia pink or brownish to blackish discolored; thallus 
     gray, granular, K-, C+ red; on burnt or decaying worked wood  
   c Apothecia variously colored; thallus reactions 
     different; mostly on tree bark                          Biatora s.l.

230a Apothecia with distinct margin of 
     same color as thallus, with algae                                231
   b Apothecia with margin of different color as thallus, 
     usually of same color as disc, or without distinct margin        234

231a Apothecia sessile with constricted base, with entire 
     or crenulate margin; disc red, K+ purplish                       232
   b Apothecia immersed, with lacerate, erect margin; disc 
     grey to pale brown, often white-pruinose                  Phlyctella

232a Spore septa thickened, about as thick as lumina; 
     spores ovoid to fusiform, less then 5 times as long as wide      233
   b Spore septa thin; spores bacillar, over five times as 
     long as wide                                              Haematomma

233a Spores two- to four-celled                                 Caloplaca
   b Spores more than four-celled                              Letrouitia

234a Apothecia without distinct margin, very soon globose      
   b Apothecia with a distinct margin, at least when young            235

235a Spores 2-loculate                                                236
   b Spores 3- or more-loculate                                       240

236a Spores 2/ascus, over 40 µm long                            Lopezaria
   b Spores 8/ascus, under 30 µm long                                 237

237a Asci with ocular chamber surrounded by I+ weakly 
     staining, rounded axial mass (Lecanora-type); spores 
     halonate; exciple with well-defined cortical and medullary 
     parts, but lacking algae                                 "Megalaria"
   b Asci without rounded, I+ weakly staining axial mass 
     around ocular chamber; spores not halonate; exciple compact      238

238a Ascus tholus containing a conical, I+ weakly staining 
     axial mass around ocular chamber                        Biatora s.l.
   b Ascus tholus containing a tubular, I+ strongly 
     staining structure; apothecia yellowish            "Catillaria" s.l.

240a Spores extremely large, broad 
     ellipsoid, 70-140 x 25-35 µm, 1/ascus                    Megalospora
   b Spores smaller or long fusiform or filiform, usually 
     8/ascus                                                          241

241a Apothecia with weak, soon inapparent margin; apothecia 
     soon convex to globose; paraphyses branched                [Micarea]
   b Apothecia with prominent, rather persistent margin; 
     disc more or less flat; paraphyses unbranched for most of 
     their length, rarely (in Fellhanera) branched                    242

242a Ascus tholus containing a more or less conical, I+ 
     weakly staining axial mass around ocular chamber                 243
   b Ascus tholus containing a tubular, I+ strongly 
     staining structure                                               245

243a Spores acicular, generally more than 5 times as long 
     as wide                                                          244
   b Spores fusiform, less than 5 times as long as wide      Biatora s.l.

244a Excipulum paraplectenchymatic; asci with rounded 
     axial mass                                        Woessia (Bacidina)
   b Excipulum prosoplectenchymatic; asci with conical 
     axial mass                                                   Bacidia

245a Excipulum with byssoid outer layer                        
   b Excipulum smooth outside                                         246

246a Apothecia usually over 0.5 mm wide, flat; I-positive 
     tubular structure in ascus apex distinctly stained over its 
     whole length                                                 Badimia
   b Apothecia mostly under 0.5 mm side, soon convex; I-
     positive tubular structure in ascus apex most distinctly 
     stained in its basal part                                 Fellhanera

250a Apothecia yellow, K+ dark purple                                 251
   b Apothecia not yellow, K-                                         252

251a Thallus white                                            Brigantiaea
   b Thallus green suffused more or less with yellow           Letrouitia

252a Ascus tholus containing a tubular I+ 
     strongly staining structure; no campylidia present; 
     paraphyses little branched                                 Lopacidia
   b Ascus tholus without tubular, I+ structure, often with 
     wide ocular chamber; usually campylidia present; paraphyses 
     strongly branched                                                253

253a Campylidia consisting of a thalloid tube and a short, 
     brownish "ear"; excipulum paraplectenchymatic            Sporopodium
   b Campylidia consisting of a large, greyish "ear" sitting 
     directly on the thallus; excipulum paraplectenchymatic     Calopadia

260a Ascocarps compound, with several, often punctiform discs 
     in raised areas concolorous with the thallus or differently 
     colored (stromatoid); spores transversely septate only           261
   b Ascocarps simple, with single disc, at age sometimes deformed 
     (not stromatoid); spores transversely septate or muriform        270

261a Thallus felty, greenish                               Dichosporidium
   b Thallus with compact upper layer                                 262

262a Discs arranged in lines, often loosely accumulated               263
   b Discs not arranged in lines, densely accumulated in 
     roundish groups                                                  264

263a Discs in whitish fields differing from the 
     thallus; thallus greenish to yellowish; spores 
     4-celled, c. 15-20 x 5 µm                      "Leucodecton" seriale
   b Discs in fields not differing from the thallus: 
     thallus whitish, dull; spores variously septate         Enterographa

264a Ascocarp discs wider, pruinose, in rounded groups        
   b Ascocarp discs punctiform, blackish                              265

265a Spores bacillar, 3-8-septate, widest above the 
     middle and gradually tapering towards both ends; no 
     red pigment in medulla                                    Chiodecton
   b Spores biclavate, 4-7-septate, with a larger and a 
     smaller swollen part; often with spotted red pigment 
     in medulla                                             Erythrodecton

270a Ascocarps without margin, adnate over 
     their whole width; asci broad-clavoid to globose, with thick 
     apical dome with large ocular chamber (Arthonia-type); 
     spores variously septate, often macrocephalic (with one terminal
     cell much larger than the others)                                271
   b Ascocarps with distinct, thalloid or lecideine margin; 
     asci elongate, with thin apical dome with small ocular chamber, 
     often surrounded by small I+ blue ring (Opegraphaceae-type); 
     spores transversely septate only, never macrocephalic 
     (terminal cells not larger than the others)                      274

271a Hymenium gelatinous, not byssoid; ascocarps clearly distinct     272
   b Hymenium byssoid, not gelatinous; ascocarps sometimes 
     scarcely distinct from thallus                                   273

272a Spores transversely septate only (when discs 
     punctiform and more or less grouped, see Enterographa)      Arthonia
   b Spores muriform                                         Arthothelium

273a Spores transversely septate only                          
   b Spores muriform                                         Cryptothecia

274a Apothecial margin carbonized throughout, black               
   b Apothecial margin not carbonized externally, whitish 
     or thalloid                                                      276

275a Ascospores acicular, 3-45-septate; disc permanently 
     black                                                  [Bactrospora]
   b Ascospores fusiform, 3-19-septate; disc often yellow-
     pruinose                                                   Cresponea

276a Apothecia with thalloid margins 
     covering a dark excipulum, not constricted at base           Mazosia
   b Apothecial margin not thalloid, without algae; often 
     constricted at base                                              277

277a Ascospores 3-septate; apothecia appressed and large, 
     often over 2 mm diam.                                  Sagenidiopsis
   b Ascospores 5-7-septate; apothecia sessile with 
     constricted base, not over 1.5 mm wide                    Lecanactis

280a Spore lumina rounded at maturity by abundant endospore       
   b Spore lumina cubical, at most with lightly rounded 
     edges, without or with scarce endospore                          290

281a Hymenium separated from the surrounding apothecium margin 
     by a split; in dry state seemingly with a double margin   Thelotrema
   b Hymenium not separated from the margin                           282

282a Margin not carbonized, apothecia immersed in the thallus         283
   b Margin at least partly carbonized and black; apothecia 
     more or less exserted                                            284

283a Apothecial margin round; discs tiny, rarely over 0.5 mm 
     wide                                                      Myriotrema
   b Apothecial margin lacerate, forming slips which cover 
     the disc in part; discs often several mm wide     "Thelotrema" pr.p.

284a Apothecia with raised thalline margin, discs visible 
     through thallus splits, pale, often white-pruinose       Ocellularia
   b Apothecia exserted above thallus, without thalloid 
     margin; discs brownish                                           285

285a Apothecia compound, with several, often elongated discs 
     level with the margin; spores hyaline, transversely septate  Glyphis
   b Apothecia simple; margin raised above the disc; spores 
     grey, muriform                                            Gyrostomum
   c Apothecia simple; margin not exserting the disc, 
     sometimes with thalline fragments; spores grey, 
     bacillar                                          Phaeographis pr.p.

290a Paraphyses branched and anastomosing throughout        
   b Paraphyses unbranched, except sometimes near the tips            291

291a Terrestrial; spores grey, muriform                     Diploschistes
   b Epiphytic, rarely on rock; spores various                        292

292a Apothecia immersed or level with thallus, often over 1 mm 
     large; margin lacerate or not                                    293
   b Apothecia sessile with constricted base, mostly under 
     1 mm large; margin entire or crenate                             294

293a Margin lacerate                                         "Thelotrema" 
                                 (perhaps better included in Chroodiscus)
   b Margin entire or inapparent                            Cyclographina

294a Apothecia proliferating from their margins and thus forming 
     coralloid-branched structures, greenish; on twigs or 
     leaf margins; spores 6-8-celled; hymenium usually absent  Polystroma
   b Apothecia not proliferating, pale yellow to orange; on 
     various substrates; spores bicellular                      Dimerella
   c Apothecia not proliferating, with carbonized excipulum 
     more or less covered by pale pruina or thallus; on mosses or 
     decaying bark or wood; spores muriform                       Ramonia

300a (201) Spores simple                                              301
   b Spores septate                                                   302

301a Spores thickwalled, spherical; paraphyses persistent     Monoblastia
   b Spores thinwalled, elongate; paraphyses disappearing 
     in an early stage                                       [Verrucaria]

302a Spores (finally) brown                                           303
   b Spores persistently colorless                                    314

303a Spore septa thin                                                 304
   b Spore septa seemingly thick, due to thickened endospore          305

304a Spores with 1-3 transverse septa; ascomata simple    Mycomicrothelia
   b Spores muriform; ascomata multilocular by lateral 
     fusion of separate ostioles                                Mycoporum

305a Spores muriform                                      Anthracothecium
   b Spores transversely septate only, with 3 or more septa           306
   d Spores uniseptate                                                307

306a Spores three- or more-septate, under 50 µm long 
     when three-septate                                          Pyrenula
   b Spores three-septate, over 70 µm long              Architrypethelium

307a Spores without pigment granules in endospore            Distopyrenis
   b Spores with pigment granules in endospore           [Granulopyrenis]

314a Spores septa seemingly thick, due to thick 
     endospore layer, causing rounded lumina; ascomata often 
     compound, in extensive pseudostromata                            315
   b Spore septa thin; ascomata usually simple                        323

315a Spores muriform                                                  316
   b Spores transversely septate only                                 319

316a Ostiole apical                                                   317
   b Ostiole lateral, free or fused                                   318

317a Ascomata in brown, usually shiny pseudostromata containing 
     yellow or orange pigments, K- or K+ red; pseudostroma 
     wall composed of brown, jigsaw puzzle-like hyphae          Bathelium
   b Ascomata not in brown pseudostromata, or wall not 
     composed of brown, jigsaw puzzle-like hyphae                 Laurera

318a Ostioles free                                      
   b Ostioles fused to other ostioles to form compound 
     ascomata                                               Cryptothelium

319a Thallus poorly developed, indicated by a 
     whitish patch on bark; ascomata naked at maturity, 
     never aggregated in pseudostromata                    Pseudopyrenula
   b Thallus well developed; ascomata immersed in thallus 
     or in pseudostromata                                             320

320a Ostioles free, apical                                            321
   b Ostioles fused to form a compound ascoma                Astrothelium

321a Paraphyses branched and anastomosing; ascus apex with narrow 
     ring surrounding a small ocular chamber; wall thickening 
     of spores most pronounced in the edges of the septae    Trypethelium
   b  Paraphyses unbranched; ascus apex with a wide apical 
     ring and wide ocular chamber; wall thickening of the 
     spore more equal (incl. Plagiotrema lageniferum)        Lithothelium

323a Ascus tip thin and uniform, truncate; 
     ascomal wall often bright colored (Trichotheliaceae); 
     paraphyses unbranched                                            324
   b Ascus tip more or less thickened with an apical 
     indentation, rounded; paraphyses often branched                  327

324a Ascomata with a subapical whorl of stiff black hairs   Trichothelium
   b Ascomata without hairs                                           325

325a Spores transversely septate; asci with chitinoid 
     apical ring (incl. Trichothelium sensu Harris 1995 pr.p., 
     Pseudosagedia)                                                Porina
   b Spores muriform; asci without chitinoid apical ring, 
     with slight subapical constriction                               326

326a Medulla white or pale yellowish                        Clathroporina
   b Medulla yellow to orange or brownish                      Myeloconis

327a Paraphyses mostly unbranched; macroconidia usually 
     present, cylindrical, septate                               Strigula
   b Paraphyses branched, especially above level of asci;
     macroconidia more or less globose or lacking                     328

328a Ascomata multilocular, chambers laterally fused with 
     separate ostioles                                                329
   b Ascomata simple                                                  330

329a Spores with 1-3 transverse septa only                   [Tomasellia]
   b Spores muriform                                            Mycoporum

330a Spores muriform                                                  331
   b Spores transversely septate                                      335

331a Asci with indistinct apical thickening; spores usually 
     8/ascus; (following Harris 1995 with inclusion of 
     Aspidothelium, with an apical disc-like expansion or 
     subapical scales on the perithecia)                       Thelenella
   b Asci with pronounced apical thickening with strong 
     ocular chamber (Arthopyrenia-like), spores 2/ascus in 
     neotropical species                                          Julella

335a Spores fusiform, 3-11-septate, over 4 µm wide; 
     asci and paraphyses as in Trypethelium                  Polymeridium
   b Spores filiform, 5->10-septate, 1.5-2 µm wide            Celothelium
   c Spores ovoid-fusiform, 1-septate, rarely 3-septate in 
     old age                                                          336

336a Lower spore cell usually the shorter; lichenized; 
     microconidia globose to ellipsoid; macroconidia often 
     present, simple, globose to ellipsoidal; ostiole often 
     lateral                                                Anisomeridium
   b Lower spore cell usually the longer; mostly non-
     lichenized; microconidia rod-shaped; macroconidia lacking; 
     ostiole always apical                                            337

337a Paraphyses slender, without refractive bodies near the 
     septa; asci clavate                                     Arthopyrenia
   b Paraphyses short-celled, with refractive bodies near 
     the septa; asci obpyriform                               Naetrocymbe

350a (201) Paraphyses branched and anastomosing; hymenium 
     I+ red or blue; spore lumina not rounded, at most with 
     slightly rounded edges; asci with rather thin apical dome with 
     small ocular chamber often surrounded by a small I+ blue ring    351
   b Paraphyses unbranched except sometimes near the tip; 
     hymenium I-, rarely pale blue; spore lumina often rounded, more 
     or less lentiform; asci usually with distinct apical dome, 
     completely I-negative                                            355

351a Ascocarp walls (labiae) conspicuous and carbonized, at 
     least internally                                                 353
   b Ascocarp walls indistinct, not carbonized                        354

353a Spores with transverse septa only; 
     excipulum externally carbonized;                           Opegrapha
   b Spores muriform; excipulum with outer thalline 
     cover; ascocarps often short lirelliform to rounded  Helminthocarpon

354a Spores muriform                                         Arthothelium
   b Spores transversely septate only                            Arthonia

355a Ascocarps in stellate or rounded clusters                        356
   b Ascocarps single                                                 360

356a Spores muriform, colorless                                Medusulina
   b Spores transversely septate only                                 357
357a Spores colorless; merocarps with rounded ends                Glyphis
   b Spores grey to brown;merocarps with pointed ends         Sarcographa

360a Spores biloculate, with cubical lumina                   
   b Spores pluriloculate, mostly with lenticular lumina 
     (when mature)                                                    361

361a Spores transversely septate only, with lenticular 
     lumina (when mature)                                             362
   b Spores muriform                                                  363

362a Spores colorless                                             Graphis
   b Spores brown                                            Phaeographis

363a Spores colorless, with or without lenticular lumina 
     (when mature)                                                    364
   b Spores grey to brown, with lenticular lumina (when 
     mature)                                                Phaeographina

364a Paraphyses unbranched, also at the tips; spore lumina 
     lenticular when mature                                      Graphina
   b Paraphyses branched and anastomosing in the 
     epithecium only, parallel below; spore lumina 
     persistently cubical                                   Cyclographina

401a (200, sterile, crustose) Thallus 
     leprose, consisting only of soredia                              402
   b Thallus byssoid, of woolly appearance while without 
     cortex and entirely composed of very loose hyphae                403
   c Thallus not leprose or byssoid. Here many usually 
     sorediate or isidiate species would key out, belonging to 
     various groups like Pertusaria, Thelotremataceae, Porina. 
     Only a selection is included here                                406

402a Thallus bright yellow, fine-grained                      Chrysothrix
   b Thallus shades of grey                                      Lepraria

403a Thallus zoned, i.e. with a differentiated 
     marginal zone, of a paler color and gradually thinning out       404
   b Thallus not zoned, usually with an abrupt border, 
     often lobed                                                 Crocynia

404a Thallus margin whitish; thallus greenish, with felty 
     isidia                                                Dichosporidium
   b Thallus margin blackish; thallus pinkish, without 
     isidia                                                 Sagenidiopsis
   c Thallus margin whitish; thallus bluegreen, without 
     isidia                                                    Dictyonema

406a Medulla with conspicuous color, yellow, orange or reddish     
   b Medulla white                                                    415

407a Medulla completely or partly red or pink; sorediate or 
     isidiate                                                         408
   b Medulla orange or yellow; sorediate                              409

408a Medulla with scattered red spots; thallus surrounded 
     by black prothallus and with soralia                   Erythrodecton
   b Medulla pink throughout; with glossy, short, 
     clavate isidia; with hypoprotocetraric acid  Ocellularia rhodostroma

409a Thallus greenish, glossy, with scattered
     soralia-like, yellow spots                                Myeloconis
   b Thallus grey, dull, with raised, often dense, 
     yellow soralia                               Megalospora "chlorites"

415a With soralia                                                     416
   b With schizidia; forest undergrowth species                       420
   c With isidia                                                      425
416a Thallus C+ red; on well-lit sites                  Pertusaria velata
   b Thallus C-; on tree trunks in forest                             417

417a Soredia fine; with stictic acid (P+ orange, K+ orange)  
   b Soredia coarse, in part corticate; with 
     hypoprotocetraric acid (P-, K-)              Myriotrema neofrondosum

420a Schizidia accumulated in groups, which may look 
     soralium-like and may be raised or shortly stalked; 
     with hypoprotocetraric acid (P-, K-)         Myriotrema neofrondosum
   b Schizidia arising single, leaving scattered scars on 
     the thallus                                                      421

421a Thallus bluegrey-pruinose; with unknown substance  
                                                           Myriotrema sp.
   b Thallus greenish, not pruinose; with various substances          422

422a Schizidia small, less than 0.2 mm wide; with 
     protocetraric acid (P+ red)                   Myriotrema parvidiscum
   b Schizidia 0.5-0.6 mm wide                                        423

423a With psoromic acid (P+ yellow, K-)           Ocellularia berkeleyana
   b With stictic acid (P+ orange, K+ orange)             Myriotrema sp.?
   c With cinchonarum unknowns (P+ red)                   Myriotrema sp.?

425a Forest undergrowth species with large, greenish, 
     glossy thalli                                                    426
   b Various habitats, thallus different                      not treated

426a Isidia cylindrical; with psoromic acid (P+ yellow) Myriotrema hartii
   b Isidia flagellate, gradually tapering from the base 
     to the tip, with basal constriction and easily 
     falling off; no lichen substances (P-)       Thelotrema brasiliensis

450a (200) Conidangia campylidia, with "ear"-shaped, 
     grey or brownish, geotropically directed extension 
     (see also couplet 181 f.f.)  "Pyrenotrichum",                    451
   b Conidangia hyphophores, brush-like with widened tip 
     carrying a gelatinous "drop"; usually immixed with 
     longer, sterile hairs                                    Echinoplaca
   c Conidangia immersed                                      not treated

451a Campylidia producing simple, pyriform or short-
     bacillar conidia                                                 452
   b Campylidia producing septate, filiform conidia                   453

452a "Ear"-shaped part short, on top of a short, thalloid 
     cylinder                                                 Sporopodium
   b "Ear"-shaped part large, directly on thallus              Musaespora

453a Campylidia grey, producing conidia without appendages     
   b Campylidia brown, producing conidia with appendages          Badimia

by Harrie Sipman, for the Biological Diversity of the Guiana Shield Program, 1997

[ TOP ]