A pan-American species already reported from the Galapagos by Weber (1986); quite abundant and widespread, mostly inland, but occasionally also coastal; mostly corticolous, rarely lignicolous. The species is not to be confused with R. sorediosa, which, in spite of its similar name, differs significantly in its thallus morphology. Ramalina sorediantha has ± flattened, in part canaliculate lobes, whereas R. sorediosa resembles a small Usnea with very thin, almost entirely terete branches that are never canaliculate.
Several specimens in CDS are currently included in R. sorediantha s.l. with some reservation. These specimens have lobes that are less obviously canaliculate than R. sorediantha s.str. They are therefore similar to R. pacifica, a species previously not reported from South America. More material should be examined to clarify the identity of these specimens.
Selected specimens examined. Ecuador: Galápagos: Isabela Island, Volcán Alcedo, in the crater, 0˚ 27’ 9” S, 91˚ 6’ 41” W, alt. 780 m, transition zone; mostly Bursera graveolens and dense scrub on uneven lava, on bark, twigs, 07 iii 2006, A. Aptroot 64751 (CDS no. 31326); outer SE-exposed slope and crater rim , 0˚ 27’ 29” S, 91˚ 7’ 19” W, alt. 1089 m, fern-sedge zone; tortoise pasture with scattered trees (Tournefortia rufo-sericea, Zanthoxylum fagara), on bark, Zanthoxylum, 05 iii 2006, A. Aptroot 65046 (CDS no. 31628); Pinta Island, along the trail up to the summit from the S-coast, 0˚ 34’ 22” N, 90˚ 45’ 3” W, alt. 329 m, transition zone; open woodland of Zanthoxylum fagara, Pisonia floribunda, and few Trema micrantha; grasses and Justicia galapagana in the understory, on bark, twigs of Zanthoxylum fagara; shaded, wind- and rain-sheltered, 27 ii 2007, F. Bungartz 5873 (CDS no. 33549); Pinzón Island, along the trail going up from Playa Escondida, 0˚ 36’ 5” S, 90˚ 39’ 54” W, alt. 225 m, arid zone with Prosopis juliflora, Alternanthera filifolia, Maytenus octogona, and Croton scouleri, on bark, twigs, 16 ii 2006, A. Aptroot 64134 (CDS no. 30697); San Cristóbal Island, crest of Cerro Tortuga, ca. 4 km inland from the NW-coast, 0˚ 44’ 54” S, 89˚ 23’ 32” W, alt. 116 m, arid zone; open Piscidia carthagenensis woodland with few Bursera graveolens and dense understory of Croton scouleri, Cordia lutea, and Mentzelia aspera on rocky SE-exposed slope of hill, on bark, twigs of Cordia lutea; sunny, wind- and rain-exposed, 25 iv 2007, F. Bungartz 6536 (CDS no. 34754); Santa Cruz Island, along the southern part of the loop road from Bellavista to Garrapatero, 0˚ 41’ 30” S, 90˚ 18’ 10” W, alt. 210 m, agricultural zone; Coffee and Guava plantations, on bark, Cedrela, 19 ii 2006, A. Aptroot 64218 (CDS no. 30784); abandoned farm along the northern part of the loop road from Bellavista to Garrapatero, 0˚ 40’ 58” S, 90˚ 18’ 31” W, alt. 255 m, agricultural zone; overgrown farm area with introduced trees like Cedrela odorata, Persea americana, Syzygium malaccense, and others; small open clearing in between, on dead wood (twigs and branches) on the ground, 19 ii 2006, F. Ziemmeck 685 (CDS no. 27547); Camote, finca de Rene valle lindero PNG, 0˚ 38’ 345” S, 90˚ 17’ 846” W, alt. 473 m, Zona húmeda, on bark, Sobre Scalesia pendunculata, corticulosos, 12 xii 2006, F. Nugra 181 (CDS no. 32835); Santiago Island, along the trail from the caseta in La Central to La Bomba, halfway down to the coast, 0˚ 12’ 54” S, 90˚ 43’ 21” W, alt. 293 m, arid zone; open woodland of Bursera graveolens and Opuntia galapageia with shrubs of Castela galapageia among basalt boulders and rocks, on bark, Castela twigs, 25 iii 2006, A. Aptroot 65613 (CDS no. 32203); outer S-exposed slope of Cerro Gavilan, 0˚ 12’ 22” S, 90˚ 47’ 6” W, alt. 815 m, moist upland; disturbed by former grazing of goats; artificial pampa with Solanum americanum, Portulaca oleraceum, Senna occidentalis, Borreria laevis, and grasses, basalt boulders and outcrops, on wood, standing dead tree, W-exposed; sunny, wind- and rain-exposed, 24 iii 2006, F. Bungartz 4806 (CDS no. 28961).
from: Aptroot, A. & Bungartz, F. (2007) The lichen genus Ramalina on the Galapagos. The Lichenologist 39(6): 519-542.