Lecanora floridula Lumbsch (1995: 569) 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 : 43-45

Lecanora floridula Lumbsch (1995: 569) MycoBank no. 413343

Type:— UNITED STATES OF AMERICA, FLORIDA: Collier County, Fakahatchee Strand State Preserve , 5 km NW of Copeland, 26°00’N, 81°20’W, sine dato, Thor , G. 4643b ( S – holotype) .

( Fig. 14A–C )

Thallus corticolous or lignicolous, moderately thickened, continuous to verruculose; surface pale yellowish green to yellowish gray, smooth epruinose, sorediate, soralia yellowish to greenish white, generally brighter in color than the thallus, pustulate, convex to coalescent in old thalli often covering and obscuring almost the entire thallus surface, soredia mealy to ±granular; prothallus a compacted, blackish brown line, occasionally indistinct. Apothecia often absent or sparse, circular in outline, 0.4–1.0 mm in diam., sessile, distinctly lecanorine with a smooth, epruinose margin concolorous with the thallus and with age often disintegrating into soredia; disc plane to slightly concave, orange brown to deep olive brown, rarely almost blackened, epruinose to indistinctly pruinose; hymenium hyaline, not inspersed, epihymenium with a weak, diffuse orange-brown pigment (cf. elachista -brown: dissolving in K, HCl± dull greenish brown, N−; adding K after N causes the formation of ca. 1 µm fuscous brown granules), both pigment and crystals soluble in K (chlarotera - type) [however: in Galapagos at least some apothecia additionally have discs discolored by an aeruginose pigment in part of their epihymenium (cinereorufa -green: intensifying in K, HCl+ bluish green, N+ reddish violet); pigment not dissolving in K (gangaleoides - type)]; proper exciple thin, indistinct, with few crystals; thalline exciple thick, ecorticate to indistinctly corticate, with large crystals insoluble in K (pulicaris - type); hypothecium hyaline; ascospores 8/ascus, simple, narrowly to broadly ellipsoid (occasionally with ±tapered ends), (8.9−)10.1−12.2(−12.9) × (4.0−)4.5−5.9(−6.9) µm (n = 25).

Chemistry: Thallus cortex, soredia and apothecial margin K− (dirty brownish yellow), rarely K+ yellow (if with atranorin), C–, KC− (dirty brownish yellow), P−, rarely P+ yellow (if with atranorin), UV−; containing usnic acid and unidentified triterpenoids; Guderley (1999) also reported atranorin and chloroatranorin, neither are present in any of the Galapagos specimens examined [specimens examined with TLC: Aptroot, A. 63741 ( CDS 30299), 64786 ( CDS 31361); Bungartz, F. 3937 ( CDS 27819), 6474 ( CDS 34691), 7077 ( CDS 37558); Weber, W.A. s.n. (L-40161, COLO 189964); Yánez-Ayabaca, A. 1794 ( CDS 48077)].

Ecology and distribution: A tropical-subtropical species, originally described from Florida ( USA), but also reported from Mexico, the Caribbean and the Galapagos ( Guderley 1999); from the coastal to the humid zone, most frequent in the dry zone, a common epiphyte, frequently also on wood.

Notes: The taxonomic status of the Galapagos representatives of this species does not appear to be well resolved. Not only are the Galapagos specimens unusual in lacking atranorin, but they are often characterized by the presence of an aeruginose, N+ purple pigment in the epihymenium. Specimens lacking atranorin were previously mentioned by Guderley (1999), but he did not observe the aeruginose pigment in L. floridula . The pigment concentration occasionally seems to be very low and in some specimens it cannot be detected.

The newly described saxicolous L. malagae (see below) closely resembles L. floridula , as both have pale greenish soredia. Lecanora malagae always has a distinctly darkened epihymenium, strongly colored by an aeruginose, N+ purple pigment. The two species are clearly distinguished by their exciple anatomy and alternative chemistry: the exciple of L. malagae lacks large crystals and specimens always contain atranorin in addition to usnic acid.

Morphologically both species closely resemble L. jamesii J.R. Laundon. However , L. jamesii differs in containing 3,5-dichloro-4- O -demethylplanaic acid and in lacking terpenes. It is not known from the archipelago.

Specimens examined. ECUADOR. GALÁPAGOS: Española, trail from Bahía Manzanillo on the N-coast of the island to the highest point, 1˚21’24.89’’ S, 89˚41’57’’W, 24 m alt., dry zone, boulder field of weathered AA-lava with scarce vegetation of Ipomoea habeliana , one Bursera tree and few Cordia lutea shrubs, dry wood of Cordia lutea , on wood, 11-Nov-2010, Bungartz, F. 9046 ( CDS 45864); along S-coast of the island, SE of Punta Suárez, 60 m inland from coast, 1˚22’58.39’’ S, 89˚43’15.4’’W, 113 m alt., dry zone, Cordia lutea shrubland with Prosopis juliflora , on old weathered trunk of Cordia lutea , 10-Nov-2010, Bungartz, F. 8927 ( CDS 45745). Floreana, Asilo de la Paz, Cerro Wittmer, trail in between cliffs, 1˚18’50’’ S, 90˚27’13.80’’W, humid zone, on trunk, 03-Jan-2010, Hillmann, G. GAL-110 ( CDS 44870); ca. 500 m S of La Lobería, ca. 200 m inland from coast, 1˚17’12.69’’ S, 90˚29’36’’W, 20 m alt., dry zone, very open Bursera forest with Waltheria ovata , few Scalesia affinis and some grasses on lava flow, on wood scar on N-exposed trunk of Bursera graveolens , 16-Jan-2011, Bungartz, F. 9751 ( CDS 47068); W of dirt road to water tank, off the main dirt road to the highlands, 1˚16’56.10’’ S, 90˚28’50.89’’W, 67 m alt., dry zone, dense Prosopis juliflora shrubland with some Castela galapageia and few trees of Bursera graveolens , on branch of Prosopis juliflora , 12-Jan- 2011, Yánez-Ayabaca, A. 1794 ( CDS 48077), 1795 ( CDS 48078); Bungartz, F. 9412 ( CDS 46699); SW of La Gigante and N of Playa de los Perros at E-coast of the island, a little bit inland from the coast, 1˚16’45.70’’ S, 90˚21’37.39’’W, 67 m alt., dry zone, very open vegetation of Cordia lutea with some Vallesia glabra , Prosopis juliflora , Parkinsonia aculeata on NE-exposed slope with some lava boulders and rocks, on top of branch, 17-Jan-2011, Bungartz, F. 9799 ( CDS 47116); at the base of Cerro Comunista, 1˚17’22.89’’ S, 90˚28’22.39’’W, 158 m alt., dry zone, dense low forest of Croton scouleri , Waltheria ovata and Castela galapageia with occasional trees of Acacia rorudiana and Bursera graveolens , on dead branch of Acacia rorudiana , 16-Jan-2011, Bungartz, F. 9699 ( CDS 47016). Pinzón, in the valley on the W-slope of the highest mountain, 0˚36’41’’ S, 90˚40’11’’W, 310 m alt., dry zone, dry zone vegetation with Prosopis juliflora , Alternanthera filifolia , Maytenus octogona , and Croton scouleri , on wood, 16-Feb-2006, Aptroot, A. 64086 ( CDS 30647). San Cristóbal, near Rosa Blanca, inland from the SE-coast of the island, 0˚49’13’’ S, 89˚21’41’’W, 13 m alt., dry zone, open Bursera graveolens woodland with Mentzelia aspera and Waltheria ovata shrubs on lava flow, on trunk of standing, dead tree, 23-Apr-2007, Bungartz, F. 6387 ( CDS 34602); Cerro Colorado, fenced off area., 0˚54’58.39’’ S, 89˚26’4.70’’W, 132 m alt., transition zone, Cordia lutea , on bark, 15-May-2006, Jaramillo, P. 2876 A ( CDS 38789); NW-slope of Cerro Colorado, close to the lighthouse, 0˚54’53.5’’ S, 89˚26’1.7’’W, 141 m alt., dry zone, upper dry zone; dense shrubland of Croton scouleri , Macraea laricifolia , few Psidium galapageium shrubs, on NW-exposed base of Bursera graveolens , 24-Aug-2008, Bungartz, F. 8616 ( CDS 41262); trail to Cerro Mundo, passing by the “cañadas”, 0˚53’32.20’’ S, 89˚34’40.5’’W, 212 m alt., transition zone, forest stand of Hippomane mancinella and Zanthoxylum fagara , with basaltic rocks covering the ground, slope 15° W, Hippomane mancinella , on bark, 25-Aug-2008, Herrera-Campos, M.A. GAL-493 ( CDS 43384); Clerc, P. 08-383 ( CDS 40237); 0˚53’33.39’’ S, 89˚34’40.10’’W, 200 m alt., transition zone, with Hippomane mancinella , Zanthoxylum fagara , Psidium galapageium , P. guajava and Kalanchoe pinnata and Mormordica charantia invading the understory, slope 10-25° WNW, on bark, 25-Aug-2008, Herrera-Campos, M.A. GAL-483 ( CDS 43374); trail to Cerro Mundo from the border of the National Park, NE of Puerto Baquerizo Moreno, 0˚53’36’’ S, 89˚34’41.5’’W, 206 m alt., transition zone, dry bed of periodical stream, forest of Psidium galapageium and Hippomane mancinella with Zanthoxylum fagara , Tournefortia rufo-sericea and Piscidia carthagenensis , on W-exposed side of Hippomane mancinella branch, 25-Aug-2008, Bungartz, F. 8652 ( CDS 41298); 0˚53’33.39’’ S, 89˚34’42.5’’W, 157 m alt., transition zone, dry bed of periodical stream with lava boulders, abundant Hippomane mancinella and few Bursera graveolens trees, on N-exposed lower trunk of Hippomane mancinella , 25-Aug-2008, Bungartz, F. 8656 ( CDS 41302), 8662 ( CDS 41308); S-slope of Cerro Mundo, shortly below the top; NE of Puerto Baquerizo Moreno and ca. 2.5 km NW of El Progreso, 0˚53’21.60’’ S, 89˚34’25.69’’W, 259 m alt., transition zone, ledge of SE-exposed basalt cliff with some Bursera graveolens trees, Croton scouleri shrubs, Zanthoxylum fagara and few Jasminocereus thouarsii , on underside of inclined Bursera graveolens trunk, 25- Aug-2008, Bungartz, F. 8694 ( CDS 41340); northern foothills of Pan de Azúcar, 0˚43’5’’ S, 89˚21’17’’W, 72 m alt., dry zone, dense woodland of Bursera graveolens , Piscidia carthagenensis , with Scutia spicata , Malvastrum sp. and Mentzelia aspera in the understory, on dead standing tree ( Piscidia carthagenensis ), 24-Apr-2007, Bungartz, F. 6474 ( CDS 34691); SW foothills of Media Luna, inland from the NW-coast of the island along the trail from Galapagera to Media Luna; bottom of small crater to the NW of Media Luna, 0˚43’53’’ S, 89˚18’57’’W, 124 m alt., dry zone, upper dry zone; woodland of Piscidia carthagenensis , Cordia lutea , Zanthoxylum fagara , Croton scouleri and few Bursera graveolens , on trunk of Bursera graveolens , 22-Apr-2007, Bungartz, F. 6261 ( CDS 34473). Santa Cruz, vicinity of Academy Bay, coastal zone, Laguncularia , on bark, 15-Feb-1964, Weber, W.A. s.n. (L-40161, COLO 189964); between Darwin Station and seismic station, dry zone, cactus forest, dead wood, on wood, 11-Feb-1964, Weber, W.A. s.n. (L-40082, COLO 188056); Nelson’s Landing, intertidal zone, loose bark flakes of Laguncularia racemosa , on bark, 27- Jan-1964, Weber, W.A. s.n. ( FH 197184); Puerto Ayora, cliff N of the town, 0˚43’59’’ S, 90˚18’45’’W, 20 m alt., dry zone, Bursera graveolens , on bark, 11-Feb-2006, Aptroot, A. 63741 ( CDS 30299); near Charles Darwin Research Station ( CDRS), 0˚44’32’’ S, 90˚18’10’’W, 5 m alt., coastal zone, on wood, 24-May-2005, Aptroot, A. 63052 ( CDS 29780); waste deposit along road to Baltra; relevee 8.2, 0˚35’0’’ S, 90˚21’17’’W, 300 m alt., transition zone, Bursera graveolens , on bark, 28-May-2005, Aptroot, A. 63255 ( CDS 29990); on the cliff behind the tortoise corral of the Charles Darwin Research Station, 0˚44’14.69’’ S, 90˚18’2.399’’W, 36 m alt., dry zone, dry zone vegetation with Opuntia and Acacia , with the influence of the sea (at ca. 1 km; presence of salt bush), S-exposed, very little slope, dead wood, on wood, 03-Aug-2008, Clerc, P. 08-05 ( CDS 39859), 08-10 ( CDS 39864); along the road from Los Gemelos towards the N-coast of the island, ca. 1 km N of Los Gemelos, 0˚37’22’’ S, 90˚22’47’’W, 584 m alt., transition zone, upper transition zone with open dry forest, Scalesia pedunculata , Chiococca alba , Tournefortia rufo-sericea , Cordia leucophlyctis , and Zanthoxylum fagara , twigs, on bark, 12-Feb-2006, Aptroot, A. 63807 ( CDS 30365); Steve Divine Farm at the end of Tortoise Road, off the main road to Baltra, Tortoise Territory, 0˚40’8’’ S, 90˚24’17’’W, 364 m alt., humid zone, agricultural area, open farmland with Cedrela odorata , Persea americana , Citrus sp. , on trunk of Cedrela odorata , 23-Feb-2006, Bungartz, F. 3937 ( CDS 27819); along the road from Bellavista to El Garrapatero, ca. 3 km from the coast, 0˚40’55’’ S, 90˚13’46’’W, 45 m alt., dry zone, deciduous dry lowland forest, Bursera graveolens , Acacia rorudiana , Opuntia echios , on rock, 14-Feb-2006, Bungartz, F. 3556 ( CDS 27355), 3557 ( CDS 27356); ca. 1 km N of Bellavista along dirt road to Media Luna, 0˚41’9.693’’ S, 90˚19’25.80’’W, 143 m alt., humid zone, farm area, coffee plantation with Cedrela odorata trees and one large Ceiba pentandra tree, on S-exposed trunk of Persea americana , 21-Oct-2007, Bungartz, F. 7072 ( CDS 37553); on S-exposed trunk of Cedrela odorata , 21-Oct-2007, Bungartz, F. 7077 ( CDS 37558); along the trail from Puerto Ayora to Bahía Tortuga, 0˚44’48’’ S, 90˚19’14’’W, 28 m alt., dry zone, deciduous forest in dry zone; with Bursera graveolens , Acacia rorudiana , and Opuntia echios ; over basalt, on trunk of Bursera graveolens , 05-Jan-2006, Bungartz, F. 3324 ( CDS 26991); above the Finca of Galo Torres, inside the Park boundary, 0˚37’45’’ S, 90˚24’1’’W, 536 m alt., humid zone, forest of mostly introduced trees ( Persea americana , Cedrela odorata , Cinchona pubescens ) and few Scalesia pedunculata , on trunk of Persea americana , 30- Jun-2006, Bungartz, F. 4990 ( CDS 29203). Santiago, along the trail from Bucanero to Jaboncillos, ca. 3 km SE of Bucanero, 0˚10’52’’ S, 90˚48’33’’W, 362 m alt., transition zone, open woodland of large Bursera graveolens and smaller Psidium galapageium trees, grassland and basalt boulders in between, dead tree, on bark, 22-Mar-2006, Aptroot, A. 65414 ( CDS 32000); 3.5 km NW of the western summit, 0˚11’0’’ S, 90˚48’15’’W, 500 m alt., transition zone, Bursera - Zanthoxylum forest on cinder cone, Bursera , on bark, 17-May-1971, Pike, L.H. ID70-13 (0, OSC 102945); E of salt lake at James Bay, 0˚14’25’’ S, 90˚49’40’’W, 70 m alt., dry zone, open Bursera forest on pahoehoe lava flow, Bursera , on bark, 30-Apr-1971, Pike, L.H. 2680 ( OSC 102823). Isabela, Volcán Alcedo, in the crater near fumaroles, 0˚27’1’’ S, 91˚7’19’’W, 780 m alt., transition zone, mostly Bursera graveolens and dense scrub on uneven lava, Bursera , on bark, 07-Mar-2006, Aptroot, A. 64786 ( CDS 31361); along the trail going up the E-slope, basalt rubble field to the SE-side of the trail and the barranco, 0˚24’3’’ S, 91˚2’35’’W, 434 m alt., dry zone, basalt rubble field with scattered vegetation ( Bursera graveolens , Zanthoxylum fagara , Pisonia floribunda , Senna pistaciifolia ), on trunk of Bursera graveolens , 09-Mar-2006, Bungartz, F. 4401 ( CDS 28486); 0˚24’7’’ S, 91˚2’55’’W, 493 m alt., dry zone, basalt rubble field with scattered vegetation ( Bursera graveolens , Zanthoxylum fagara , Pisonia floribunda , Senna pistaciifolia ), on dead standing trunk, 10-Mar-2006, Bungartz, F. 4425 ( CDS 28511), 4427 ( CDS 28513), 4428 ( CDS 28514), 4430 ( CDS 28516), 4431 ( CDS 28517); 0˚24’6’’ S, 91˚2’53’’W, 530 m alt., dry zone, basalt rubble field with scattered vegetation ( Bursera graveolens , Zanthoxylum fagara , Pisonia floribunda , Senna pistaciifolia ), Bursera , on bark, 10-Mar-2006, Aptroot, A. 64915 ( CDS 31494); outer SE-exposed slope and crater rim, 0˚27’29’’ S, 91˚7’19’’W, 1089 m alt., humid zone, tortoise pasture with scattered trees ( Tournefortia rufo-sericea , Zanthoxylum fagara ), on wood, 05-Mar-2006, Aptroot, A. 65091 ( CDS 31673). Volcán Darwin, southwestern slope, above Tagus Cove, 0˚13’59’’ S, 91˚20’8’’W, 597 m alt., dry zone, open Bursera graveolens forest with Croton scouleri and Macraea laricifolia shrubs, few Chiococca alba and Scalesia microcephala , among lava boulders and outcrops, on SW-exposed trunk of Bursera graveolens , 16-Nov-2007, Bungartz, F. 7853 ( CDS 38362); Volcán Sierra Negra, area around the Muro de las Lagrimas, ca. 5 km W of Puerto Villamil, 0˚57’54.27’’ S, 91˚0’48.77’’W, 81 m alt., dry zone, open Bursera graveolens forest on NNE-exposed slope with Opuntia echios , Scalesia affinis and Lantana peduncularis , on NEexposed, dead tree stump, 17-Aug-2008, Bungartz, F. 8411 ( CDS 41057).

Figures

FIGURE 14. Sorediate species in the L. subfusca-group; epihymenium at least in part aeruginose. A–C. Lecanora floridula A–B. Morphological variation. A. Thallus pale greenish gray, rimose-areolate, with pustulate yellow green soralia and broadened apothecia with deep brown disc (Bungartz, A. 8616, CDS 41262). B. Thallus rimose, yellow green, with pustulate yellow green soralia, apothecia indistinct, disc barely expanded, dark brown (Bungartz, F. 6474, CDS 34691). C. Apothecial section (in water, DIC): exciple with large crystals (pulicaris-type), epihymenium mostly brown, with few crystals (chlarotera-type), but in parts also aeruginose (Aptroot, A. 64915, CDS 31494).D–G. Lecanora malagae (Bungartz, F.10352, CDS 52326–holotype).D. General thallus aspect,composed of inflated,closely aggregated, pale gray areoles with pustulate pale yellowish green soralia, apothecia with a thick margin, disc bluish blackened, faintly pruinose. E. Close-up of the thallus. F. Lecanora-type ascus, tholus with wide, apically open, unstained central cone and deeply stained ascus flanks (in Lugol’s, DIC). G. Apothecial section (in water, DIC): exciple with minute crystals only (allophana-type), epihymenium aeruginose, lacking crystals (gangaleoides-type). Scales: A, D, B & E = 5 mm; F = 10 µm; C & G = 100 µm.