Diagnosis. Similar to B. fungicola, but with abundant ciliary bulbs all across its surface, isidia and apothecial margins; lobes wider and the surface always lacking maculae; cilia and rhizines dichotomously branched; ascospores smaller and ±globose; the type containing lecanoric acid.
Type: South America, ECUADOR: Galapagos: Isabela, Volcán Darwin, southwestern slope, above Tagus Cove, 0°13’57.9”S, 91°20’5.1”W, 613 m, transition zone, SW-exposed lava flow of weathered AA-lava with scarce vegetation (Macraea laricifolia, Croton scouleri, Dodonaea viscosa, Scalesia microcephala, Cordia revoluta and Opuntia insularis), on bark of branches of Croton scouleri; sunny, wind- and rain-exposed, 11-Dec-2007, Bungartz 7393 (cds 37880 - holotype selected here!).
Thallus up to ca. 10 cm wide, corticolous, greenish gray becoming dusky gray in the herbarium, upper cortex 25.0–35.0 µm thick; algal layer 95.0–100.0 µm thick, medulla white, 137.0–142.0 µm thick, lower cortex 17.5–20.0 µm thick. Lobes 1–2 mm wide, moderately broadened to sublinear, not distinctly laciniate, dichotomously or trichotomously anisotomously branched, contiguous, adnate, strongly attached; aices plane, truncate to subtruncate; margin plane, smooth to sinuous or subirregular, entire, sparsely to densely ciliate, axils oval; adventive lobes generally rare and sparse, very short, randomly distributed along the margins, simple, flat, 0.2–0.5 × ca. 0.7 mm, truncate, underside concolorous with the lower margin. Upper surface continuous to rarely cracked (older parts), smooth, with numerous, immersed to semi-immersed ciliary bulbs; maculae absent, sometimes with scars from isidia that have broken off. Cilia black, simple, occasionally becoming furcate and then mostly dichotomously, rarely irregularly branched, ca. 0.05–0.15 × 0.03 mm, with semi-immersed to emersed basal bulbs ca. 0.05 mm wide, sparse to abundant along the lobe margins, spaced ca. 0.05 (–0.10) mm from each other to contiguous, typically confined to the lobe axils and absent at the lobe apices; well developed cilia confined to the thallus margin, but ciliary bulbs extending all across the thallus surface, including isidia and the margin of apothecia. Soredia and pustules absent. Isidia scarce to abundant, laminal, granular to cylindrical, ca. 0.05–1.00 × 0.05 mm, simple to sparsely branched, occasionally slightly contorted, erect, firmly attached to caducous, concolorous with the thallus, apically darkening (brownish), typically densely “peppered” with black ciliary bulbs. Lower surface black, ±shiny, smooth to subrugose and moderately to densely rhizinate in the center; along the margin becoming light brown, smooth to papillate, occasionally with few rhizines. Rhizines light to dark brown or black, initially simple, soon becoming dichotomously or irregularly branched, occasionally with inconspicuous basal bulbs, ca. 0.07–0.55 × 0.03 mm, frequent to abundant, evenly distributed. Apothecia laminal, adnate, flat, up to ca. 1.5 mm wide; margin smooth to subrugose, coronate with ciliary bulbs and short isidia; disc light brown, epruinose, imperforate; epihymenium 12.5–15.0 µm, hymenium 35.0–43.0 µm, subhymenium 87.5–95.0 µm; ascospores globose to subglobose 5.5–6.0 × 5.0–5.5 µm, epispore ca. 0.7 µm thick. Pycnidia not observed (among the abundance of immersed ciliary bulbs no pycnidia were found).
Chemistry. Cortex with atranorin, medulla with lecanoric and possibly also gyrophoric acid (see discussion below).
Etymology. Named for the ciliary bulbs on its thallus surface, isidia and apothecial margin.
Distribution and ecology. Neotropical; newly described from Galapagos (recorded from the islands Española, Floreana, San Cristóbal, and Volcán Darwin on Isabela) from the dry to the transition zone in sunny, rarely semi-shaded, mostly wind & rain-exposed, rarely ±sheltered habitats, on stems, branches and twigs of native trees and shrubs, most frequently on bark of Bursera graveolens and Croton scouleri, also on Macraea laricifolia and Zanthoxylon fagara; one specimen on introduced Guava trees (Psidium guajava).
Specimens examined. C+ bright red, with lecanoric acid confirmed by TLC: Ecuador. Galapagos Islands: Isla Floreana, inside the crater of Cerro Laguna at E-side of island, on W-exposed slope, 1˚ 16’ 11.80” S, 90˚ 23’ 17.00” W, 245 m alt., 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 cutains from Clerodendrum twigs, on twigs of Bursera graveolens; sunny, wind- and rain-exposed, 20-Jan-2011, Bungartz, F. 9948 (CDS 47317). Isla San Cristóbal, sector of the "Gotera de agua", trail to Cerro Pelado, 0˚ 51’ 51.00” S, 89˚ 27’ 36.39” W, 402 m alt., upper transition zone, open area within the forest with shrubs of Psidium guajava and Macraea laricifolia, and Malachra capitata covering the ground, flat plane, on Psidium guajava, 23-Aug-2008, Clerc, P. 08-287 (CDS 40141). Isla Isabella, Volcán Darwin, southwestern slope, above Tagus Cove, 0˚ 13’ 57.89” S, 91˚ 20’ 5.09” W, 613 m alt., SW-exposed lava flow of weathered AA-lava with scarce vegetation (Macraea laricifolia, Croton scouleri, Dodonaea viscosa, Scalesia microcephala, Cordia revoluta and Opuntia insularis), on branches of Croton scouleri; sunny, wind- and rain-exposed, 11-Dec-2007, Bungartz, F. 7393 (CDS 37880); Bungartz, F. 7698 (CDS 38201); Bungartz, F. 7708 (CDS 38210). C+ bright red, only gyrophoric acid confirmed by TLC, lecanoric acid not confirmed: Ecuador. Galapagos Islands: Isla Española, trail from Bahía Manzanillo on the N-coast of the island to the highest point, 1˚ 21’ 24.89” S, 89˚ 41’ 57.00” W, 24 m alt., boulder field of weathered AA-lava with scarce vegetation of Ipomoea habeliana, one Bursera tree and few Cordia lutea shrubs, on branches of Bursera graveolens; sunny, wind- and rain-exposed, 11-Nov-2010, Bungartz, F. 9040 (CDS 45858). 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 base of Macraea laricifolia; sunny, wind- and rain-exposed, 18-Jan-2011, Yánez, A. 2014 (CDS 48364). Isla San Cristóbal, Cerro Colorado, enclosure for Calandrinia galapagosa near the viewpoint on the top, 0˚ 54’ 58.00” S, 89˚ 26’ 5.00” W, 130 m alt., open scrubland of mostly Croton scouleri, Waltheria ovata, and Macraea laricifolia on W-exposed cinder cone, on stems and branches of Croton scouleri; sunny, wind- and rain-exposed, 29-Apr-2007, Bungartz, F. 6756 (CDS 35007); on top of Cerro Colorado, 0˚ 54’ 55.79” S, 89˚ 26’ 3.89” W, 145 m alt., upper dry zone; open shrubland of Croton scouleri, Macraea laricifolia and Waltheria ovata with lava boulders, on stem of Croton scouleri, S-exposed; sunny, wind- and rain-exposed, 24-Aug-2008, Bungartz, F. 8594 (CDS 41240). Isla Isabela, Volcán Darwin, southwestern slope, above Tagus Cove, 0˚ 13’ 27.60” S, 91˚ 19’ 21.19” W, 860 m alt., open scrubland of Dodonaea viscosa, Croton scouleri, Macraea laricifolia, Scalesia microcephala, few Opuntia insularis and dry grasses in the understory, on twigs of Croton scouleri; sunny, wind- and rain-exposed, 15-Nov-2007, Bungartz, F. 7704 (CDS 38206); southwestern slope, above Tagus Cove, 0˚ 14’ 15.40” S, 91˚ 20’ 40.29” W, 351 m alt., open Bursera graveolens forest with Croton scouleri, Macraea laricifolia and Waltheria ovata, few trees of Acacia rorudiana, on top of inclined Zanthoxylum fagara branch; semi-shaded, wind- and rain-sheltered, 16-Nov-2007, Bungartz, F. 7896 (CDS 38405).
from: Bungartz, F., Benatti, M.N. & Spielmann, A. (2013) Parmeliaceae of the Galapagos Islands, part I: The genus Bulbothrix Hale. The Bryologist116(4): 358–372. https://doi.org/10.1639/0007-2745-116.4.358