Cladia aggregata Nyl. 1870

Cladia aggregata (Sw.) Nyl. (1870: 167)

(Figs. 1a–b)

Primary thallus not seen, evanescent, of lobulate-papillate squamules (according Ahti, 2000); pseudopodetia erect, forming cushions or dense mats, dark brown or pale yellowish, 4–4.5 cm tall, hollow, terete to ± flattened or angulate, some parts, when older, densely branched; branching anisotomic, dichotomous; surface corticate, glossy or matt; usually abundantly perforate; perforations frequently ellipsoid; pycnidia with hyaline jelly; apothecia not seen.

Spot tests and chemistry: P−, K− or + yellow, C−, KC−, UV−; barbatic and 4- O -demethylbarbatic acid (chemotype I).

Distribution and ecology: Currently know only from the humid zone in the highlands of Isabela and Santa Cruz; on bare, sunny, exposed soil, often along trails and in reindeer lichen heaths.

Notes: The cushions or dense mats of this species may at first be mistaken for a reindeer lichen but, the genus Cladia is easily recognized because it has completely corticate pseudopodetia with abundant ellipsoid perforations.

According to Ahti (2000) the fertile pseudopodetia typically represent the thickest branches. Fertile material was, however, not encountered among the Galapagos specimens and this observation cannot be confirmed here.

Selected specimens examined: ECUADOR. GALAPAGOS: Isabela Island, Volcán Cerro Azul, S-slope above Iguana Cove, crater on SE-slope, 800 m, humid zone, 22 June 1976, Sipman, H.J.M. L-58 (L, COLO 297902). Santa Cruz Island, SE of El Puntudo, W of Mt. Crocker, 1972, Weber L-55403 (DUKE, H, TUR), saddle between Mt. Crocker and El Puntudo, 750–800 m, 1976, Weber & Lanier, Lich. Exs. COLO 497 (DUKE, H, TUR, U, QCA, FH 197181, COLO 297764), NE-slope of El Puntudo, 0°38’39.10”S, 90°20’7.90”W, 813 m, humid zone, on open soil among Cladonia spp. 10 Aug 2008, Bungartz, F. 8151 (CDS 40797), along the trail from Media Luna to El Puntudo, at a small stream crossing the trail, 0°39’4”S, 90°20’5”W, 690 m, humid zone, bare ground along the footpath, 28 Jan 2006, Bungartz, F. 3971 (CDS 27901).