Basionym: Parmelia laevigatula Nyl., Flora 68: 614. 1885.

Lectotype: East Africa, French Guinea: Cayenne, Leprieur 504 (H-Nyl 35653!, isotype in PC!).

Thallus corticolous, greenish gray becoming pale dusky gray in the herbarium; medulla white. Lobes ca. 0.5–1.5 (–2.0) mm wide, sublinear to moderately laciniate, dichotomously or trichotomously branched, contiguous to slightly imbricate, adnate, firmly attached; apices subtruncate to truncate; margin smooth to sinuous or subcrenate. Upper surface continuous to occasionally cracked (older parts), smooth, lacking laminal ciliary bulbs; maculae absent; adventive lobes generally rare and sparse, short, randomly distributed along the margins. Cilia black, simple to eventually furcate and then subdichotomously or irregularly branched, abundant, but confined to the lobe margins, with basal bulbs. Soredia and pustules absent. Isidia common, laminal, simple to sparesly branched, eciliate. Lower surface ±shiny, smooth to subrugose, black and densely rhizinate throughout, rarely with a distinct, narrow deep brown smooth to papillate, weakly rhizinate marginal zone. Rhizines black to dark brown, simple to eventually furcate, dichotomously or irregularly branched, abundant and equally distributed, rarely with inconspicuous basal bulbs. Apothecia rare (not observed in Galapagos specimens), if present laminal to submarginal, sessile to subpedicelate, subconvex to concave; margin smooth to subcrenate, ecoronate, rarely isidiate; disc brown, epruinose, imperforate; ascospores globose to ellipsoid or oval, 6.0–8.0 ( −11.5) × 4.0–5.0 (−6.0) µm, epispore ca. 0.5 (−1.0) µm thick (Benatti 2010, Hale 1976). Pycnidia laminal; conidia baciliform to weakly bifusiform 5.0–7.5 × 0.75 µm.

Spot test reactions. Cortex K+ yellow, C−, KC−, P+ yellow, UV− (dull); medulla K−, C+ bright red, KC+ bright red, P−, UV− (dull).

Chemistry. Cortex with atranorin, medulla with lecanoric acid.

Distribution and ecology. Cosmopolitan, reported from Asia (Japan, Philippines, Thailand), Africa (Angola), North- (USA, Mexico), Central (Costa Rica, Caribbean Islands) and South America (Columbia, Ecuador, Peru, Venezuela, Brazil) (Benatti 2010); previously reported from Galapagos by Weber (1986), and Elix & McCarty (1998); together with B. subdissecta the most common species of Bulbothrix in Galapagos (recorded from the islands Floreana, Pinta, San Cristóbal, Santa Cruz, Santiago, Volcán Cerro Azul and Volcán Sierra Negra on Isabela), it has been found in the dry and transition zone, in sunny, rarely semi-shaded, mostly wind & rain-exposed, rarely ±sheltered habitats, where it grows on stems, branches and twigs of native trees and shrubs, most frequently on bark of Bursera graveolens and Psidium galapageium; no specimen has been found on introduced phorophytes.

Specimens examined. Ecuador. Galápagos Islands: Isla Floreana, lower S-slope of Cerro Ventanas, permanent plot 3, 1˚ 16’ 36.10” S, 90˚ 25’ 41.10” W, 295 m alt., open shrubland of Macraea laricifolia and some lower Waltheria ovata shrubs in between, on fallen branch, 18-Jan-2011, Yánez, A. 2024 (CDS 48374); SE-part of island, between Lechosos and Cerro Pajaros, slope opposite Cerro Pajaros, permanent plot 4, 1˚ 18’ 26.10” S, 90˚ 24’ 21.39” W, 278 m alt., upper transition zone; mixed forest of Psidium galapageium and Croton scouleri with Macraea laricifolia on NNW-exposed slope, on branch of Psidium galapageium; sunny, 15-Jan-2011, Yánez, A. 1926 (CDS 48279); trail from Black Beach to highlands, 0˚ 0’ 0” , 0˚ 0’ 0” , m alt. on Bursera, 25-Apr-1976, Weber, W.A. s.n. (CDS 294599). Isla Pinta, along the trail up to the summit from the S-coast, 0˚ 34’ 5” N, 90˚ 44’ 57” W, 237 m alt., open woodland with Bursera graveolens, Zanthoxylum fagara, Opuntia galapageia, Pisonia floribunda, Croton scouleri, and with Alternanthera filifolia shrubs and grasses in between, on trunk of Bursera graveolens (ca. 25 cm in diam.), W-exposed; sunny, wind- and rain-exposed, 28-Feb-2007, Bungartz, F. 5945 (CDS 33623); near volcano in the south-central part, 150 m alt., in open forest, on Bursera, 08-Jul-1976, Sipman, H.J.M. L-119 (CDS 297841). Isla San Cristóbal, Cerro Mundo, at the base of the rock cliffs on the S side close to the summit, 0˚ 53’ 32.20” S, 89˚ 34’ 40.50” W, 243 m alt., with Bursera graveolens, Croton scouleri, Piscidia carthagenensis, Zanthoxylum fagara and a few Scalesia pedunculata, slope 45° ESE, on branches of Cordia lutea at the base of the cliff, 25-Aug-2008, Truong, C. 1527 (CDS 39838); Cerro Partido along trail from entrance to Cerro Pelado to El Ripioso, 0˚ 51’ 23” S, 89˚ 27’ 37” W, 376 m alt., rocky SW-exposed slope of hill with Jasminocereus thouarsii, Clerodendrum molle var. glabrescens, Psidium galapageium, Bromeliaceae and ferns growing in rock crevices, on twigs of Psidium galapageium, S-exposed; sunny, wind- and rain-exposed, 28-Apr-2007, Bungartz, F. 6588 (CDS 34808); near Tres Palos, 350 m alt., on Psidium, 22-May-1976, Lanier, J. s.n. (CDS 298407); plane between Cerro Pelado and Cerro Partido, S of El Ripioso, 0˚ 51’ 31” S, 89˚ 27’ 34” W, 372 m alt., dense scrubland with Croton scouleri, Clerodendrum molle and Macraea laricifolia, on branches of Zanthoxylum fagara; semi-shaded, wind- and rain-sheltered, 28-Apr-2007, Bungartz, F. 6667 A (CDS 34903); sector of the "Gotera de agua", trail to Cerro Pelado, 0˚ 51’ 34.60” S, 89˚ 27’ 35.20” W, 389 m alt., with Bursera graveolens, Zanthoxylum fagara and Lantana camara invading the understory, slope 15° N, on dead Zanthoxylum fagara, 23-Aug-2008, Clerc, P. 08-307 (CDS 40161); W of the cemetery of El Progresso at the border of the National Park, 0˚ 54’ 44.79” S, 89˚ 34’ 34.00” W, 170 m alt., at the edge of a forest of native and introduced trees (Hippomane mancinella, Tamarindus indica, Leucaena leucocephala, Clerodendrum molle and vines), on NW-exposed branch of Hippomane mancinella; shaded, wind- and rain-sheltered, 24-Aug-2008, Bungartz, F. 8566 (CDS 41212); Wreck Bay, 380 m alt., 15-Feb-1964, Itow, S. s.n. (CDS 190279); vicinity of Academy Bay, 15-Feb-1964, Weber, W.A. s.n. (CDS 188560). Isla Santiago, E of salt lake at James Bay, 0˚ 14’ 25.00” S, 90˚ 48’ 50.00” W, 170 m alt., Bursera-Psidium forest on pahoehoe lava flow, on Bursera twigs, 30-Apr-1971, Pike, L.H. 2719A (CDS 53383); summit of Cerro Gavilan, outer S-exposed crater rim, 0˚ 12’ 23.00” S, 90˚ 46’ 57.00” W, 840 m alt., S-exposed, steep basalt cliffs of crater rim with ferns (Pityrograma calomelanos var. calomelanos, Polypodium tridens, Dryopteris palmata, Adiantum concinnum, Blechnum polypodioides) growing in crevices, on Psidium, 23-Mar-2006, Aptroot, A. 65495 (CDS 32084). Isla Isabela, Volcán Cerro Azul, path from the fist Caseta del Parque to Caleta Iguana, appox. half of the way, abandonned finca "La Lima", 0˚ 59’ 1.10” S, 91˚ 26’ 17.10” W, 198 m alt., dense, shaded woodland of large, predominantly introduced fruit trees (abandonned finca); Citrus spp. (Lima, Limon, Naranja), Carica papaya, but also some natives like Croton scouleri, pega pega (Pisonia floribunda), on inside forest, perturbated area, semi-shaded, epiphytic, 08-May-2012, Spielmann, A. 10708 (CDS 52076); S-slope above Iguana Cove, 1600 m alt. on Psidium galapageium, 10 cm in diam., 24-Jun-1976, Sipman, H.J.M. L-83 (CDS 297878); Volcán Sierra Negra, Isabela Island, area around the Muro de las Lagrimas, ca. 5 km W of Puerto Villamil, 0˚ 57’ 54.29” S, 91˚ 0’ 48.79” W, 81 m alt., open Bursera graveolens forest on NNE-exposed slope with Opuntia echios, Scalesia affinis and Lantana peduncularis, on E-exposed branch of Bursera graveolens; sunny, wind- and rain-exposed, 17-Aug-2008, Bungartz, F. 8426 (CDS 41072).

from:
Bungartz, F., Benatti, M.N. & Spielmann, A. (2013) Parmeliaceae of the Galapagos Islands, part I: The genus Bulbothrix Hale. The Bryologist 116(4): 358–372.