Thallus olive green to blackish grey when dry, darker when wet, foliose, adnate to ± loose, moderately thick; outline irregular; lobes indistinct, broad; surface smooth, dull, irregularly nodulose, but not broadly pustulate, occasionally fenestrate; lacking true isidia, but often broadly lobulate with conch-like ascending lobes; apothecia sessile, laminal, expanded; disk deep reddish brown, flattened to becoming slightly convex; margin lecanorine, concolorous with thallus, with a broad, loosely prosoplectenchymatous outer thalline exciple, and a distinct inner paraplecten­chymatous proper exciple; ascospores vermiform, with rounded ends, ± coiled inside the ascus, typically 3-5 septate, 35-40 x 3-5 µm.

Substrate & Ecology: Rare, known only from three collections, on bark of Bursera, Clerodendrum, and Tournefortia; all in the transition zone (see below).

Distribution: New to the Galapagos; currently known only from Santiago and Isabela (Volcán Alcedo).

Notes: The species can easily be recognized by the strongly nodulose thallus with abundant, slightly convex apothecia and vermiform spores that are often ± coiled inside the ascus.

Specimen examined: Isabela Island: Volcán Alcedo, outer SE-exposed slope, ca. 500 m below the crater rim, 0˚27’13”S, 91˚5’46”W, 1035 m, fern-sedge zone; Paspalum conjugatum with scattered shrubs of Tournefortia rufo-sericea, on bark of Tournefortia, 3 Jun 2006, Aptroot 64844, CDS no. 31420. Santiago Island: along the trail from Bucanero to Jaboncillos, ca. 200 m below the summit, Cerro Gavilan, 0˚12’9”S, 90˚47’3”W, 796 m, upper transition zone; open Psidium galapageium forest with Zanthoxylum fagara, dense understory of Clerodendrum molle, Tournefortia pubescens and others, on bark of Clerodendrum molle; sunny, wind- and rain-exposed, 23 Mar 2006, Bungartz 4738, CDS no. 28849; along the trail from Bucanero to Jaboncillos, ca. 5 km SE of Bucanero, 0˚11’19”S, 90˚47’48”W, 562 m, transition zone; open woodland of large Bursera graveolens and smaller Psidium galapageium trees with Blainvillea dichotoma, Mentzelia aspera and Senna obtusifolia, on bark of Bursera graveolens, W-exposed; semi-shaded, wind- and rain-sheltered, 22 Mar 2006, Bungartz 4655, CDS, accession no. 28742.

from:
Bungartz, F. (2008) Cyanolichens of the Galapagos Islands - The genera Collema and Leptogium. Sauteria 15: 139-158.