Lecanora oreinoides (Körb.) Hertel & Rambold (1989: 100) MycoBank

Bungartz, Frank, Elix, John A. & Printzen, Christian, 2020, Lecanoroid lichens in the Galapagos Islands: the genera Lecanora, Protoparmeliopsis, and Vainionora (Lecanoraceae, Lecanoromycetes), Phytotaxa 431 (1), pp. 1-85 : 14-15

Lecanora oreinoides (Körb.) Hertel & Rambold (1989: 100) MycoBank no. 125874

Type:— AUSTRALIA. Exact locality unknown, original label data: “ Ad saxa arenaria Novae Hollandiae ” (= on sandstone in New Holland), sine dato, Hofstetter, F. 25 [L 910.134-2202– lectotype selected by Hertel (1973)] .

( Fig. 3C–D )

Thallus saxicolous, thick,contiguous, rimose-areolate, fissures with undulating to barely crenate edges, closely adjoining but not interlocked; surface white to creamish beige, smooth, epruinose to roughened, lacking soredia; prothallus consisting of a thin compact, blackened line, most pronounced where different thalli meet, occasionally extending between the areoles and thus discoloring the margins. Apothecia sparse to numerous, circular, cryptolecanorine, immersed, not emerging, with a plane to slightly depressed, epruinose disc, margin not to barely differentiated from the surrounding thallus, 0.1–0.8(–0.8) mm in diam.; hymenium hyaline, not inspersed, epihymenium with diffuse aeruginose pigment (cinereorufa -green: intensifying in K, HCl+ bluish green, N+ reddish violet), lacking crystals (gangaleoides - type); proper exciple thin, rarely moderately developed, apically olivaceous due to a mixture of a brown pigment (elachista -brown: dissolving in K, HCl± dull greenish, N−) and an aeruginose pigment (cinereorufa -green), basally reddish brown (elachista -brown), occasionally with few large crystals that do not dissolve in K; thalline exciple not clearly differentiated from surrounding thallus; hypothecium hyaline to pale yellowish (intensifying in K); ascospores 8/ascus, simple, broadly ellipsoid to subglobose, (5.9–)6.7–8.1(–8.9) × (4.0–)4.6–5.7(–5.9) µm (n = 50). Pycnidia not seen [according to Ryan et al. (2004)]: immersed, conidia filiform, 10–16 × ca. 0.8 µm.

Chemistry: Thallus cortex P+ yellow, K+ yellow, KC−, C−, UV− (dull), medulla P−, K−, KC−, C−, UV−; with atranorin [major], confluentic acid [major], ±2'- O -methylmicrophyllinic acid [minor]; [specimens analyzed with TLC: Bungartz, F. 6789 ( CDS 36208); Weber, W.A. s.n. ( CDS 10821)].

Ecology and distribution: Widely distributed in subtropical to tropical, or even temperate regions (North and South America, Africa, Asia, Australasia, Oceania), new to Ecuador and the Galapagos; from the coastal zone through the dry into the transition zone, apparently absent from the humid zone, but re-appearing again in the upper dry zone; mostly in open habitats, on ±exposed, sunny rock, rarely semi-shaded and ±sheltered.

Notes: This saxicolous species is morphologically very similar to L. subimmersa , but it does not contain zeorin and unlike L. subimmersa ssp. ramboldii , always lacks xanthones. The apothecial discs are also diagnostic as they are always partially blackened by cinereorufa -green, an olive green, N+ reddish violet pigment which is absent in the similar L. legalloana (microscope!). Unlike L. legalloana and L. subimmersa , the thalline areoles of L. oreinoides are undulate to crenate, but are not tightly interlocked by serrate margins.

Specimens examined. ECUADOR. GALÁPAGOS: Floreana, trail from Black Beach to highlands, 25-Apr-1976, Weber, W.A. s.n. (L-62903, COLO 294618); lower S-slope of Cerro Ventanas, 1˚16’36.10’’ S, 90˚25’41.10’’W, 295 m alt., transition zone, open shrubland of Macraea laricifolia and some lower Waltheria ovata shrubs in between, on rock, 18-Jan-2011, Bungartz, F. 9856 ( CDS 47194); inside the crater of Cerro Laguna at E-side of island, on W-exposed slope, 1˚16’11.80’’ S, 90˚23’17’’W, 245 m alt., transition zone, dense forest of Prosopis juliflora , Clerodendrum molle , very few Bursera graveolens and some Jasminocereus thouarsii in the upper part among lava outcrops and boulders; Ramalina usnea /anceps hanging in curtains from Clerodendrum twigs, on rock, 20-Jan-2011, Bungartz, F. 9964 ( CDS 47333); trail going to Post Office Bay off the dirt road between highlands and Puerto Velasco Ibarra, cliff at NE-side of trail (Mirador), 1˚17’4.298’’ S, 90˚26’36.60’’W, 365 m alt., transition zone, ca. 10 m high lava cliff within dense scrub of Clerodendrum molle , Croton scouleri and Macraea laricifolia , one single Acacia rorudiana on top of cliff, on rock, 25-Jan-2011, Bungartz, F. 10211 ( CDS 47630), 10205 ( CDS 47624). ECUADOR. GALÁPAGOS: San Cristóbal, rim of crater to the NW of Media Luna, inland from the NW-coast, 0˚43’51’’ S, 89˚18’55’’W, 149 m alt., transition zone, lower transition zone; basalt cliffs of inner and outer crater rim with scarce vegetation, on rock, 22-Apr-2007, Bungartz, F. 6297 ( CDS 34509). Santa Cruz, vicinity of Academy Bay, E of Research Station, coastal zone, aerohaline belt, 15-Feb-1964, Weber, W.A. s.n. (L-40862, COLO 190339), s.n. (L-40871, COLO 190380); barranco near seismic station, dry zone, 15-Feb-1964, Weber, W.A. s.n. (L-40867, COLO 190334); 20 m alt., dry zone, lava rocks, on rock, 12-Apr-1976, Weber, W.A. s.n. ( CDS 10821); 0.8 km E of Darwin Station, coastal zone, shore boulders just above high tide level, on rock, 15-Feb-1964, Weber, W.A. s.n. (L-40067, COLO 188280), s.n. (L-40039, COLO 185676); along the road from Bellavista to El Garrapatero, ca. 2 km from the coast, at the campsite of the National Park, 0˚41’25’’ S, 90˚13’35’’W, 24 m alt., dry zone, deciduous dry lowland forest, Bursera graveolens , Acacia rorudiana , Opuntia echios , Croton scouleri , top of basalt boulder; sunny, wind- and rain exposed, on rock, 14-Feb-2006, Bungartz, F. 3568 ( CDS 27367). Santa Fé, S-exposed side of lava flow at the N-coast of the island, 0˚48’6.20’’ S, 90˚2’39.77’’W, 42 m alt., dry zone, S-exposed side of lava flow with scarce vegetation (shrubs of Croton scouleri , Cordia lutea , few Bursera graveolens trees, and Opuntia echios var. barringtonensis ), on rock, 25-Oct-2007, Bungartz, F. 7271 ( CDS 37755). Santiago, E of salt lake at James Bay, 0˚14’25’’ S, 90˚48’50’’W, 17 m alt., transition zone, Bursera - Psidium forest on pahoehoe lava flow, on rock, 30-Apr-1971, Pike, L.H. 2726 ( OSC 53377). Isabela, Volcán Cerro Azul, outer, lower, densely vegetated slopes of the crater rim, 0˚57’9.096’’ S, 91˚24’23.19’’W, 1470 m alt., high altitude transition zone, dense grassy pasture with abundant Low Rattlebox (Crotolaria pumila), few, large basalt boulders, scarce Tournefortia rufo-sericea scrub and sparse Guayabillo ( Psidium galapageium ) trees, on rock, 06-May-2012, Bungartz, F. 10380 ( CDS 52350). Volcán Sierra Negra, top of the northern crater rim, 0˚48’3’’ S, 91˚5’25.89’’W, 968 m alt., humid zone, SW-exposed basalt cliffs among dry vegetation of grasses and herbs, on rock, 08-Sep-2007, Bungartz, F. 6781 ( CDS 36200), 6789 ( CDS 36208).

Figures

FIGURE 3. Species in the L. marginata-group. A–B. Lecanora legalloana (Bungartz, F. 9366, CDS 46653). A. Rimose-areolate thallus composed of interlocked, crenate areoles, with immersed, deep reddish brown apothecia. B. Apothecial section with deep brown epihymenium, exciple with few large and abundant minute crystals. C–D. Lecanora oreinoides (Bungartz, F. 6781, CDS 36200). C. Thallus areolate, apothecia immersed, black. D. Apothecial section: exciple barely differentiated from surrounding thallus, epihymenium aeruginose. E–F. Lecanora subimmersa (Bungartz, F. 6311, CDS 34523). E. Rimose-areolate thallus composed of interlocked, crenate areoles, with immersed, deep reddish brown apothecia. F. Apothecial section with deep brown epihymenium, exciple with few large and abundant minute crystals, barely differentiated from surrounding thallus. Scales: A, C & E = 5 mm; B, D & E = 100 µm.