LICHENS Key to Genera
LICHENS KEY TO GENERA
CRUSTOSE
6
Thallus lacking, parasitic on other lichens, mature spores pale with a green tinge, 1-3-septate, 6-11(-14) × 2-4 µm
Thallus present, not parasitic on other lichens, mature spores dark brown, 1-septate, 14-19 × 8-11 µm
10
Fruiting bodies perithecia or perithecia -like; fruits, globose, opening by a minute pore at apex (use ×10 lens)
Fruiting bodies apothecia; fruits discoid, the disc ± exposed at maturity, concave to globose, sometimes immersed, or in the form of elongate, short or stellate lirellae, marginate or immarginate
11
Hymenial algae (2 µm diam.) within perithecium; spores muriform
13
Thallus supracuticular; spores 3-7-septate; perithecia with a crown of stiff, outward-pointing, marginal hairs
Hypophyllous (near margins of underside of leaf); paraphyses branched and anastomosing
16
Apothecia present, perithecia-like, immersed in thalline warts; laminal cephalodia present; thallus K+ yellow-orange; spores large, 40-70 × 20-30 µm, wall 4 µm thick; mainly corticolous, rarely saxicolous
Perithecia present; laminal cephalodia absent; thallus K-; spores less than 30 µm long and 15 µm wide; saxicolous or terricolous
20
Ascocarps combined in a stroma with a common, carbonaceous covering (involucrellum) with 8-30 pores; spores elongate, 3-20-septate
24
Paraphyses persistent, net-like; spores 1-septate, not or rarely constricted at septum, uniseriate in ascus
Paraphyses ± evanescent; spores 1-3(-4)-septate, often constricted at septum, clustered or ± biseriate in ascus
25
Saxicolous; spores thin-walled, 1-3-septate, not constricted at septa; paraphyses evanescent
Corticolous; spores 1-septate, very thick-walled, constricted at septum; paraphyses persistent, branched, anastomosing
26
Spore wall minutely warted (use oil immersion); spores 1-septate, septa thin, constricted at septum
27
Ascocarps mainly discrete, rarely 2-5-confluent but not united in a stroma; spores oblong-ellipsoid, 3-7-septate, locules of spores lens-shaped or rhomboidal; xanthones often present (UV ± orange)
Ascocarps aggregated (2-9) in ± rounded, well-defined stromata; spores oval-ellipsoid, 3-septate, locules of spores rounded to diamond-shaped, xanthones absent (UV-)
30
Exciple fused to thalline rim, blackened; spores 1 per ascus, 120-210 × 30-35 µm
Exciple detached from thalline rim, not blackened; spores 2-8 per ascus, 35-130 × 10-25 µm
32
Corticolous, not peeling from substratum, prothallus absent; ostioles of perithecia not gaping-dilated; paraphyses anastomosing, net-like; spores 30-300 × 11-65 µm
Corticolous and saxicolous, often peeling from substratum or ± easily detached, prothallus often present; ostioles of perithecia often gaping-dilated; paraphyses sparingly branched; spores 40-150 × 22-40 µm
33
Corticolous; thallus of small scales, surface often papillate (use microscope ×400+)
34
Apothecia present, perithecia-like, with a distinct, overarching thalline rim forming a ± discrete or gaping pore, disc often ± visible within
35
Perithecia discrete; paraphyses anastomosing; spores oblong-ellipsoid 35-52 × 8-13 µm
Perithecia mostly united (1-4) in a common stroma; paraphyses unbranched; spores broadly ellipsoid 30-70 × 11-35 µm
36
Apothecia ± lirellate, elongate, branched or stellate, discrete or clustered, marginate or immarginate, or ± irregularly rounded, sessile, to subimmersed or embedded in raised pseudostromata, never discoid
40
Spores brown, 3-5-septate, 17-22 × 6.8-8.3 µm, apothecial disc white-pruinose
41
Apothecial disc brown, irregularly branched, radiate-flexuose; spores I+ deep blue-violet, ellipsoid-fusiform, 5-10-septate, 32-50 × 7-8.5 µm; paraphyses simple
Apothecial disc red-brown to black, aggregated or regularly arranged following shape of individual pseudostromata; spores I-, acicular, flexuose, 3-septate, 30-55(-70) × 2-3(-4) µm; paraphyses netlike
47
Spores I+ deep blue-violet, 3-11-septate, septa thick, locules lenticular; paraphyses simple
48
Saxicolous; apothecia minute, punctiform, discrete, straight or sinuous; spores 20-24 × 10-12 µm
Corticolous; apothecia irregular, rounded or elongate, ± contorted; spores 15-18 × 5-8 µm
51
Ascocarps usually ± innate, with an eroded, "rubbed-down" appearance; ascus ± rounded; spores 2-8 per ascus, colourless or brown
Ascocarps prominent, swollen; asci cylindrical; spores 8 per ascus, colourless, 24-27 × 7-13 µm.
56
Thallus orbicular, ± placodioid, marginal lobes ± clearly differentiated, inner part of thallus remaining ± intact; thallus and apothecial disc K+ purple (parietin); spores 8 per ascus, 9-12 × 2.5-5 µm
Thallus granular-dispersed, spreading, not placodioid; thallus and apothecial disc K-; spores 8, 16 or 32 per ascus
59
Mainly corticolous; apothecia perithecia-like, immersed in hemispherical warts; cephalodia pale, ± concolorous with thallus; thallus K+ yellow-orange, C-; spores large 40-70 × 20-32 µm, thick-walled
Saxicolous or terricolous; apothecia sessile to sub-pedicellate, discs ± broadly exposed, pale to dark red-brown, pink or blackened; cephalodia yellowish, red-brown or pinkish; thallus K- or pale yellow (P. salazina K + yellow → orange), C+ pink or red; spores thin-walled 12-30 × 6-21 µm
61
Spore wall thin; spores (6-) 8 per ascus; ascocarps always discrete, disc ± widely exposed
Spore wall thick; spores 8 or fewer per ascus; ascocarps discrete or several together forming irregular, fertile verrucae, or ± immersed; disc small and punctiform to broad and lecanorine
62
Terricolous; thallus ± pruinose; apothecia immersed, urceolate, discrete; spores 8 per ascus 36-52 × 24-30 µm
Corticolous or saxicolous, rarely terricolous (P. dactylina); apothecia innate within verrucae generally elevated above thallus surface, disciform with monocarpic fruits producing single-walled spores in lecanorate or sorediate verrucae, or poriform with polycarpic fruits producing double-walled spores
63
Apothecia biatorine, bursting through thallus cortex (collar of thalline tissue soon disappearing), cortex C+ red (lecanoric acid)
64
Apothecia sessile, margins persistent at maturity; paraphyses not, or ± clavate at apices, not moniliform; spores less than 15 µm long; hymenium less than 100 µm tall
Apothecia ± innate, margins often not evident at maturity; paraphyses moniliform at apices; spores more than 15 µm long, hymenium more than 100 µm tall
68
Apothecia bursting through thallus cortex, pale collar of thalline tissue soon disappearing; cortex C+ rose-red (lecanoric acid)
Apothecia not bursting through thallus cortex, never with collar of thalline tissue; cortex C- or + red or orange (not lecanoric acid)
70
Thallus pale brown-grey or olivaceous with a black, marginal prothallus; epithecium red-brown; hypothecium pale brown or colourless; paraphyses with distinctly swollen, brown apices, pigment in walls
Thallus pale grey-green; marginal prothallus present or absent; epithecium green-blue to blue-black; hypothecium red-brown to greybrown; paraphyses not, or only very slightly, swollen at apices, without pigment in walls
71
Thallus ± rust-red, areolate; apothecia small (0.1-0.5 mm diam.), ± innate, disc concave; hymenium < 100 µm tall; spores 10-15 µm long
Thallus grey, rarely partly buff, rimose; apothecia large (to 4 mm diam.), ± sessile, margins prominent, swollen; hymenium to 160 µm tall; spores 15-33 µm long
Thallus crustose forming neat, well-defined patches; corticolous; apothecia sessile
74
Apothecia subgyrose-contorted, proper margin often obscuring disc; exciple blackened at least in outer part; on calcareous rock
Apothecia biatorine, immarginate; exciple not blackened; corticolous or lichenicolous
80
Thallus orbicular ± placodioid, marginal lobes clearly differentiated, inner part of thallus remaining ± intact; thallus and apothecial disc K+ purple (parietin); spores 8 per ascus, 9-12 × 2.5-5 µm
Thallus granular dispersed, spreading, not placodioid; thallus and apothecial disc K-; spores 8, 16 or 32 per ascus
82
Apothecia large (1-3 mm diam.); disc pink, thallus K+ orange; spores 1 - (rarely 3-) septate; on rotting wood
Apothecia minute (0.2-0.5 mm diam.); disc red-brown or black, K-; spores 1-3-septate; corticolous
84
Apothecia brown-pink to ± black; spores oblong-ellipsoid, straight, 8-16 × 2-3 µm; pycnidial walls K+ purple
Apothecia orange or mustard-yellow, never blackened; spores fusiform-ellipsoid; pycnidial walls not K+ purple
85
Apothecia mustard-yellow to testaceous, ± immarginate, spores 10-25 µm long
Apothecia orange, with a pale, prominent proper margin; spores 6-14 µm long
87
Thallus brown-black to black, papillate or ± coralloid-granular, often with a blue-black prothallus; photobiont blue-green; on limestone
Thallus pale grey-white, greenish or brownish, never black, crustose or areolate, sometimes forming a squamulose crust; photobiont green
91
Corticolous; spores 5-7-septate, 12-16 per ascus; asci and hymenial gelatine I+ blue
Saxicolous; spores 3-septate, 8 per ascus; asci and hymenial gelatine I+ yellow-brown
96
Apothecia ± innate or ± level with thallus surface, rounded to irregular, ± white-pruinose and often appearing soredia-like, concolorous with thallus or paler; thallus ± arachnoid, whitish or pale green or grey
97
Apothecial discs rounded, red, pink or orange, sometimes white-pruinose; spores 1-3-, 5-8-, 11-13-septate; twigs and tree trunks, occasionally on rock
Apothecial discs irregular, ± stellate, furcate or lirellate, black or brownish, epruinose; spores 3-septate; on dry bark of old trees
98
Disc translucent when wet; spores 8-32 per ascus, acicular, 68-80 × 3-4 µm
100
Thallus citrine-yellow; spores 8-10(-12)-septate, acicular, 35-60 × 2-5 µm
Paraphyses branched, anastomosing; hypothecium hyaline; on acid rocks or among mosses
Hypothecium ± translucent, colourless or variously coloured, never opaque brown-black; photobiont Trebouxia -like
104
Corticolous; hymenium 120-125 µm tall, inspersed with oil droplets; thallus Pd+ orange (pannarin); spores large, ovoid, 3-septate, septa thick, 40-80 × 16-32 µm
Foliicolous; hymenium 30-60 µm tall, not inspersed with oil droplets; thallus Pd-; spores ellipsoid, 3-8-septate, septa thin
105
Apothecia elongate to angular (triangular or quadrangular), margin formed of dark tissue which at first covers disc; spores 6-8 septate, 13-23 × 5-10 µm
Apothecia ± rounded, disc black, margins distinctly byssoid; spores 3-septate, 10-17 × 3-5 µm
107
Exciple fused to thalline rim, blackened; spores 1 per ascus, 120-210 × 30-35 µm
Exciple detached from thalline rim, not blackened; spores 2-8 per ascus, 50-104 × 15-24 µm
110
Apothecia red-brown, ± gelatinous and semi-translucent when wet; hyphae of exciple and hymenium loosely netted in a common gelatinous matrix; muscicolous
Apothecia not gelatinous, margins not translucent when wet; paraphyses simple or branched, not anastomosing; exciple different in structure from hymenium; corticolous or saxicolous, rarely muscicolous (Brigantiaea fuscolutea)
114
Thallus pale green-grey, matt, Pd+ orange (pannarin); apothecia brown, ± pruinose; spores ovoid, transverse septa thick, 45-80 × 23-32 µm
Thallus yellow-grey to glaucous-brown, translucent when wet, Pd-; apothecia red-brown to black, epruinose; spores oblong-cylindrical, transverse septa thin, 75-110 × 9-14 µm
117
Apothecia urceolate, with a thalline margin; thallus C+ red (lecanoric acid)
119
Exciple fused to thalline rim, blackened; spores 1 per ascus, 120-210 × 30-25 µm
Exciple detached from thalline rim, not blackened; spores 1-2 per ascus, 95-190 × 25-42 µm
120
Apothecia crowded into convoluted, ± cerebriform thalline verrucae; spores 1 (rarely 2) per ascus, 60-240 × 32-100 µm
121
Thallus subarachnoid, granular-scurfy, white or grey-white, not areolate; spores oblong-ellipsoid to fabiform, submuriform (sometimes 3-5-septate); paraphyses ± simple; on limestone
Thallus distinctly areolate, not granular-scurfy, yellow-green, ashy grey, brownish, rarely white; spores ovoid or broadly ellipsoid; paraphyses conglutinate, netted; on acid rocks
Thallus partly sorediate or if wholly sorediate with intermingled short, pale cartilaginous stalks
127
Terricolous; white efflorescent soralia on greyish, spreading thallus; usually on exposed clay banks, paths etc, Pd+ yellow-orange
Corticolous; pale grey inconspicuous, ± obscured by scattered or contiguous, efflorescent pale green-white soralia; Pd+ rust red
*In Arthopyrenia sens. lat., some taxa may have smooth spore walls and also persistent paraphyses.
*In Arthopyrenia sens. lat., some taxa may have smooth spore walls and also persistent paraphyses.
** See also Microthelia (p.295).
† N.B. Lecidea, in this circumscription is still very much a dustbin genus and urgently in need of accurate delimitation. As represented in New Zealand it is undoubtedly heterogeneous.
‡ Apothecia occasionally surrounded at base by a spurious thalline margin.
PLACODIOID
Thallus blue-grey, grey to ± olivaceous, matt or scabrid; on sub-alpine-alpine soils or acid rocks
134
Upper surface with red-brown, pinkish or yellowish cephalodia; cortex C+ red or pink; on subalpine-alpine soil and rocks, mainly inland
135
Thallus buff-brown to blackish, not pruinose; ascocarps perithecia; intertidal
Thallus white to pale grey-white, often pruinose; ascocarps apothecia, rare; above high tide mark
SQUAMULOSE
142
Squamules minute, sorediate, granular-furfuraceous; walls of pseudopodetia, if present, perforate; apothecia minute, peltate, black
143
Squamules and pseudopodetia pale green or olive-brown, never yellowish (usnic acid absent); pseudopodetia uniformly terete, finger-like, not ridged, striate or fissured; apothecia black
Squamules and pseudopodetia yellow-green or yellow-brown (usnic acid); pseudopodetia ridged-striate-fissured, apothecia yellow-pink or brownish, never black
144
Apothecia large (2-6 mm wide), ± flattened-undulate, spathulate, disc ventral
145
Squamules shell-like, small, blue-grey, often discrete or ± imbricate, sorediate; fruits unknown
147
Thallus ± lobulate-crustose, granular-dispersed, marginal lobes indistinct
Thallus minutely but distinctly lobate, best seen at margins, ± densely granular-sorediate
150
Hymenial algae present, 2 µm diam.; spores brown, muriform, 2 per ascus
152
Cephalodia present; apothecia lecanorine; spore wall roughened-ornamented
153
Marginal prothallus present, black; thallus dark brown-black; terricolous
154
Thallus microphylline, ± coralloid; apothecia brown, orange-red or red-brown; hypothecium massive, chondroid
Thallus ± peltate or shell-like, 1.5-6 mm diam.; apothecia black or brown-black; hypothecium shallow
156
Squamules 3-6 mm diam., concave, contiguous or scattered, salmon pink to chestnut brown, often white-pruinose; apothecia marginal, convex, black; on calcareous rock and soil
Squamules 1.5-2 mm diam., convex, imbricate, ascending, glaucous-green to whitish, pruinose, occasionally sorediate, lower cortex orange-brown or yellowish; apothecia glaucous-brown to purplish-black, convex, confluent
157
Thallus lettuce green, not pruinose, rosette-forming, white below; apothecia pink; spores 1-septate
Thallus white, yellow-brown, red-brown, grey or blackish, often white-pruinose, lobulate, hummocky to ± granular-areolate; apothecia black spores 1-3(-7)-septate
158
Attached by a ± central umbilicus; apothecia rare, immersed; spores 60-100 per ascus; sorediate
Attached over whole of lower surface, without a central umbilicus; sorediate or fertile; spores 8 per ascus
159
Squamules nodular-papillate to ± subfruticose, in caespitose mats, dark greyish-brown to black above, brown or tan below; marginal prothallus absent; terricolous, subalpine
Squamules flattened, broad and rounded to laciniate, incised, microphylline or lobulate, blue-green or bluish-grey, red-brown or fawnish, whitish below, with conspicuous white or blue-black rhizines; marginal prothallus present or absent
160
Marginal prothallus absent, squamules red-brown or grey-brown, elongate, ascending, crowded-imbricate; spores 1-2-septate
Marginal prothallus often present, blue-grey or blue-green or fawn above, squamules variable, ± flattened or undulate, rounded to crenate, scattered to imbricate; spores simple
Apothecia without thalline margin (photobiont absent from margin), proper margin present
FOLIOSE
162
Thallus foliose, of horizontally-spreading lobes, leaf-like, dorsiventral, the upper surface differing in colour from the lower which is usually corticate, attached to substratum by rhizines, tomentum or part of lower cortex, usually easily detached from substratum
169
Thallus usually brown-black or greenish-black, often ± pulpose or swollen when wet; cellular cortex on upper and lower surfaces absent (microscople); without hairs below
Thallus blue-grey or brownish or greyish-black, not generally swollen when wet; often with pale hairs below; cortex of 1-cell thickness on upper and lower surfaces (microscope)
171
Lower surface smooth, pale buff to brown-red; spores simple, 100+ per ascus, (in dry, ± arid areas)
Lower surface corrugate-faveolate, white; spores 2-3-septate, 8 per ascus (subantarctic, subalpine)
172
Lower surface ± distinctly veined; apothecia marginal; spores elongate, septate, colourless
173
Thallus mainly of thin coralloid to squamulose blue-green cephalodia surrounding ± urceolate apothecia with a thin margin containing green algae; spores brown, 1-septate
Thallus not coralloid, ± rosette-forming or lobate; apothecia sessile to subpedicellate, on lamina or at margins or on lower surface of lobes; spores colourless
176
Upper surface scabrid-areolate or verrucose; apothecia lecideine (without photobiont in margin)
177
Thallus ± placodioid, especially at margins; apothecia ± innate; spores septate
178
Thallus thick, coriaceous, ± uniform, lobes cuneate-flabellate, with dense pale or blue-black rhizines below, but without a distinct felted prothallus
Thallus thin, often uneven-ridged or wrinkled, lobes not cuneate-flabellate, often with a distinct, blue-black, felted, marginal prothallus
179
Apothecia adnate§, often irregular in outline, without proper or thalline margins
Apothecia sessile, regular in outline, with a visible proper margin, thalline margin present or absent
Apothecia lecideine (photobiont absent from margin), proper margin only present
181
Lower surface finely pubescent or ± glabrous, rhizines absent; apothecia, when present, on lower surface of marginal lobes
Lower surface tomentose, often with large naked patches, rhizines present, scattered singly or in bundles; apothecia when present, laminal
185
Thallus irregularly submonophyllous; ascocarp a perithecium, ostioles visible as numerous black dots on upper surface; on wet rocks
186
Thallus unattached, ± flattened when wet, curling up into balls when dry
Hypothallus discontinuous, in bead-like patches; upper surface yellowish (usnic acid)
194
Upper surface with perforations (rarely imperforate and then with isidia); spores large, thick-walled, 2 or 8 per ascus; physodic acid absent
Upper surface without perforations or isidia; spores small, 8 per ascus; physodic acid present
198
Pseudocyphellae ± elongate, often forming a coarse, white reticulum; medulla K+, C-
Pseudocyphellae punctiform, scattered, not forming a coarse reticulum; medulla K-, C+ (rose or red)
200
Lobes ± ascending (6-10 mm wide) densely rhizinate below, rhizines felted, with a network of veins; on soil
Lobes ± flat, evenly attached, not or rarely ascending, lower surface corticate, not feltlike or with veins
201
On rocks, soil, glass, slate rarely spreading to mosses; apothecia laminal; spores colourless, simple
On bark or twigs, rarely on rocks; apothecia on lower surface of marginal lobes; spores reddish-brown, 3-septate
204
Lobes broad, rounded (10-30 mm wide), with a broad, brown, naked, marginal zone on lower surface
206
Lobes 0.4-1.5 mm wide, loosely dichotomously branching; upper surface fibrous, without maculae; lower surface ecorticate, arachnoid, with subapical soralia; medulla K-
Lobes 4-8 mm wide, dichotomously branching; upper surface maculate (×10 lens) sorediate at apices; lower surface shining, corticate; medulla K+ yellow → red (salazinic acid)
207
Thallus closely attached even at apices; lobes 1-4 mm wide, sublinear to subirregular; lower surface black; rhizines black, simple to squarrose; spores simple, colourless
Thallus adnate to ascending; lobes 0.5-3 mm wide, irregularly to dichotomously branching; lower surface white to pale brown; rhizines whitish to dark brown, simple; spores 1-septate, brown
211
Thallus closely attached, even at apices; lobes variable (5-15 mm wide) sublinear, apically obtuse to subirregular, apices rounded; spores colourless, simple, thin-walled
Thallus closely to loosely attached, often ± ascending at apices; lobes dichotomously to irregularly branching, (0.5-3 mm wide); spores brown, thick-walled, 1-septate
213
Thallus greyish, colour little changed when wet, upper surface K+ yellow (atranorin)
214
Lobes 1-3 mm wide, upper surface and apothecial discs ± white-pruinose; lower cortex prosoplectenchymatous or absent, rhizines squarrose; medulla not orange-pigmented
Lobes 1 mm wide, upper surface and apothecial discs epruinose; lower cortex paraplectenchymatous with isodiametric cells, rhizines simple; medulla sometimes orange (skyrin)
218
Lobes broad, rounded, margins notched, little divided; mazaedium on marginal lobules
Lobes rather narrow, richly divided, digitate-laciniate or palmate; mazaedium on ascending fertile branches
219
Upper surface with minute, punctiform pseuduocyphellae (× 10 lens); lower surface sparsely rhizinate
Upper surface without pseudocyphellae; lower surface rhizinate centrally, with a broad, brown, shining naked marginal zone
220
Lower surface pubescent, rhizines absent; apothecia when present on lower surface of marginal lobes
221
Thallus large, 5-20(-60) cm diam., spreading; lobes rounded to linear-laciniate; spores colourless, fusiform-acicular, 1-3(-7)-septate, wall smooth
Thallus 5-10 cm diam., ± rosette forming; spores simple or 1-3-septate, thin- or thick-walled, colourless or brown, ellipsoid or oval-ellipsoid
223
Terricolous, humicolous; apothecia pink, thalline margin absent, spores 1-septate at maturity
Corticolous; apothecia lecanorine with a conspicuous thalline margin; cephalodia absent or present, spores simple, wall often ornamented
224
Thallus brown or grey-brown, greenish when wet; spores of Pachysporaria -type
Thallus pale to dark grey or grey white, not greenish when wet; spores of Dirinaria -type
* See also Lempholemma (p. 245).
§ When sterile, specimens of Coccocarpia and Degelia are difficult to distinguish. As a general rule, thalli of Coccocarpia are thinner and rather more fragile than those of Degelia.
FILAMENTOUS
225
Thallus filamentous, very fine, soft, hair-like or felt-like, fungal hyphae enveloping algal filaments or chains
Thallus fruticose, shrubby, tufted, erect, ascending or pendulous, attached by a basal disc or holdfast, or unattached and ± decumbent, main branches cylindrical (terete) or ± flattened, internal structure radial, arranged around a central cord-like strand (as in Usnea) or around a central cavity (as in Cladonia), when flattened, upper and lower surfaces may be the same colour (as in Ramalina) or the lower surface may be paler than the upper surface (as in Sphaerophorus)
227
Photobiont green, Trentepohlia; mycobiont brown-black, hyphae distinct, contorted
228
Thallus tufted, in small, pulvinate rosettes, filaments paired, recurved, photobiont Scytonema; apothecia lateral; asci (16-) 24-spored, spores 7-11 × 5-8 µm; on limestone
230
Thallus blue-green, rhizines present; photobiont Hyphomorpha; spores not seen
Thallus brownish-black, rhizines absent; photobiont Scytonema; spores muriform, brown-black
231
Thallus blue-green, fibrillose, shelf-like, zonate; basidiocarps irregularly spreading, whitish or creamish, on underside of thallus
Thallus pale green, olive or whitish, felted or woolly, not shelf-like, not zonate; apothecia present
232
Thallus pale green to yellow-olive, felt-like or fluffy; apothecia orange-yellow, spores 1-septate
233
Thallus white; apothecia sessile, small (0.3-0.4 mm diam.), pale pink, immarginate; spores simple, 5-7 × 1-1.5 µm
Thallus grey-white, greenish-white or yellowish-white; apothecia subpedicellate, to 1 mm diam., white-pruinose; spores 5-6-septate, (22-)25-30 × 3-8 µm
FRUTICOSE
237
Basal crust emerald green; apothecia large, convex, globose to conglomerate, brown, on hollow ± fenestrate stalks, without soredia or isidia; on rotting wood or on bryophytes
Basal crust white, grey or green, isidiate or sorediate; apothecia stalked or sessile, stalks solid, not fenestrate; on soil or rock
238
Basal crust grey or green, with or without soredia, without isidia; apothecia convex or plane, with a pale proper margin, pink, orange-pink or reddish, on stalks or ± sessile; spores 8 per ascus
Basal crust white, isidiate, isidia papillate to columnar; apothecia in fertile verrucae embedded in tips of isidia, white, concolorous with isidia; spores 1 per ascus
239
Fruiting body an impermanent yellow or orange toadstool; basal crust of gelatinous green globules; on soil
Fruiting body simple to lacerate or lobed stalks, not a toadstool, white to pale yellow or ochre-pink, slimy, ± translucent; basal crust bright green, slimy, translucent when wet; on rotting wood
241
Apothecia expanded, to twice as wide as supporting branch or wider; thalline exciple massive, ± cupuliform, coarsely wrinkled-scabrid; disc slightly concave to plane; spores large, broadly cylindrical-ellipsoid, muriform, 1-2 per ascus
Apothecia rarely wider than supporting branch; thalline exciple rarely well-developed, often obscured by disc which is frequently convex-subglobose; spores narrowly elongate-fusiform, 1-13-septate, 8 per ascus
242
Basal squamules minute, sorediate granular-furfuraceous; apothecia minute, peltate, clustered, black
243
Secondary thallus hollow, blunt, pointed or cup-forming, simple or branched; apothecia terminal, red, pale or dark brown or brown-black
244
Squamules and pseudopodetia pale green or olive-brown or red-brown, never yellowish (usnic acid absent); pseudopodetia uniformly terete, finger-like, not ridged, striate or fissured; apothecia black
Squamules and pseudopodetia yellow-green (usnic acid present); pseudopodetia ridged, striate or fissured; apothecia yellow-pink or red-brown
245
Apothecia large (2-6 mm wide) on ventral surface of flattened apices, spathulate, undulate
249
Thallus simple or sparingly branched, often with ± ascending squamules; apices tapered or terminated by cups or sometimes with convex to conglomerate, brown or red apothecia
Thallus repeatedly and intricately branched, without squamules; apices without cups or conspicuous apothecia
250
Thallus ± consistently and conspicuously perforate (clathrate-fenestrate); surface smooth, ± shining or with crystalline excrescences
254
On marine rocks in lower supralittoral zone; tufted; to 5 mm tall; in small colonies 5-10 mm diam., sometimes coalescing to form swards; lobes terete (even towards base); dull olive-brown to black
256
Basal stalk well-defined; pale fawnish or greyish, pubescent, terete or in part flattened; upper parts copiously branched-dendroid; always sterile
Without a well-defined basal stalk, broadly attached, cushion-like; branches complex-entangled; apothecia common, orange-yellow with a pale proper margin; spores 1-2 septate
259
Thallus yellow or green-yellow or pale greenish or occasionally suffused reddish-brown, lacking black banding or annulation; apothecial discs yellow to green-yellow
Thallus ± yellow near base, often black or violet-black above, at least at apices, often with conspicuous black banding and annulation; apothecial discs black
263
Thallus black, grey, often pale straw-coloured or whitish or pinkish towards base; branches with distinct, white, often raised pseudocyphellae (×10 lens); C+ rose red
Thallus olivaceous, brown or brown-black; branches with or without indistinct, flat or concave pseudocyphellae; C-
266
Thallus large (7-20 cm tall) tree-like; attached by a thick hold-fast of brown, branching rhizoids; upper branches spreading-dendroid; isidioid branchlets in fasciculate groups; a canopy species
Thallus smaller (1-10, rarely to 25 cm tall); upper parts not spreading-dendroid; isidioid branchlets scattered, not in fasciculate groups; on tree trunks, never or rarely in canopy branches
267
Apothecia expanded, twice as wide as supporting branch or wider; thalline exciple massive, ± cupuliform, coarsely wrinkled-scabrid; disc slightly concave to plane; spores large, broadly cylindrical-ellipsoid, muriform, 1-2 per ascus
Apothecia rarely wider than supporting branch; thalline exciple rarely well-developed, often obscured by disc which is frequently convex-subglobose; spores narrowly elongate-fusiform, 1-13-septate, 8 per ascus
268
Apothecia on elevated fertile branches; spores colourless, grey or brown, in a powdery mass (mazaedium)
269
Thallus yellow-green (usnic acid); small, inconspicuous white, linear pseudocyphellae (×10 lens) often present
Thallus pale greenish-white, of simple or sparingly branched, short, pale cartilaginous stalks, densely covered with white or greenish, granular soredia; on lowland and coastal rocks and soil
271
Upper (dorsal) surface green or grey-green; mazaedium present on elevated, fertile branches; lower (ventral) surface white
273
Corticolous, rarely saxicolous; lowland often coastal; yellow-green (usnic acid); attached by a basal disc or holdfast but without a distinct rooting system; laminal and marginal white pseudocyphellae present (×10 lens)
Terricolous; alpine or subalpine; with a distinct (often delicate) rooting system; laminal pseudocyphellae absent
274
Thallus laterally compressed; white or tinged bluish, fawn, cream, greenish or reddish; sterile (fruits unknown)
Thallus inflated-terete; red-brown above, fawnish or olivaceous below; fertile; apothecia black, lecideine, terminal
* See also Gonohymenia (p. 171).
