Thallus corticolous, rarely saxicolous, delimited by a distinct byssoid prothallus of white, radiating hyphae; thallus surface cottony, ecorticate, greenish gray to grayish white, with storage beige, lacking soredia; medulla white, densely filled with minute colorless granules and sparse calcium oxalate crystals (insoluble in KOH, forming colorless, needle-shaped crystals in 25% H2SO4); ascigerous areas developing in the thallus center as small, byssoid dots that soon merge into distinctly radiating striae, rarely not forming striae, but merging into large pustular outgrowths (not true soredia); asci bitunicate-fissitunicate, broadly pyriform to globose, with a short stalk, a moderately thickened wall (ca. 4-6 μm) and thick tholus with small ocular chamber, individual asci irregularly dispersed, isolated to loosely grouped, not closely aggregating, entangled by few, IK+ violet-blue paraphysoids, occasionally surrounded by diffuse brownish pigment, not carbonized; ascospores hyaline, K-, ovoid to oblong, occasionally slightly bent, muriform, with curved septa, (46-)55-70(-80)×(19-)23-29(-37) μm, 1(-2) per ascus; conidiomata not observed.

Spot tests and chemistry: P-, K-, C+ bright red, KC+ bright red; UV- (pale yellowish green); medulla ILugol’s+ deep blue; gyrophoric and/or lecanoric acid, ±traces of atranorin.

Distribution and ecology: Cosmopolitan, new to Galapagos and Ecuador; the most common Cryptothecia species in Galapagos, often very abundant, especially in the humid and upper transition zone, rarely also in the dry zone, on a wide range of mostly native, but also introduced tree species, typically in ±shaded and sheltered habitats.

Notes: Aptroot et al. (2009) report two specimens collected in Galapagos as Herpothallon philippinum. We were unable to locate specimen Aptroot 54328 in CDS and were thus unable to examine the specimen and confirm its identification. The second specimen cited as Aptroot 64330 (CDS accession no. 30895) contains psoromic acid and thus belongs to Herpothallon echinatum. Reports of H. philippinum therefore cannot be confirmed for Galapagos.

Morphotypes of thalli that do not form very distinct striae, but are instead abundantly covered in pustular outgrowth within which the asci develop have previously erroneously been reported as C. punctosorediata (Bungartz et al. 2010b). Sparrius & Saipunkaew (2005) emphasize that in C. punctosorediata the thallus does not react with C, but that only the soredia contain gyrophoric acid and thus react C+ bright red. For C. punctosorediata they also report asci with six to eight ascospores.

The pustules of the Galapagos material previously identified as C. punctosorediata are not true soredia, but they clearly represent the ascigerous regions in which asci with one, rarely two, never eight ascospores develop. Thalli and pustules contain lecanoric acid and both react distinctly C+ bright red; this reaction is clearly not confined to the pustules only. Finally, unlike reported for C. punctosorediata by Sparrius & Saipunkaew (2005) the material does not fluoresce conspicuously white under UV light.

Selected specimens examined: Ecuador: Galapagos: Isla Floreana, Asilo de la Paz, Cerro Wittmer, road to Post Office Bay, 1°18’41”S, 90°27’4”W, humid zone, on bark, 03-Jan-2010, Hillmann GAL-82 (CDS 44908); ca. 1 km S of Cerro Verde, 1°18’34”S, 90°25’19”W, alt. 299m, transition zone, on bark, 15-Jan-2011, Yánez 1954 (CDS 48306); ca. 200m from the northern limit of the Primavera Farm in the highlands of the island, 1°18’48”S, 90°26’7”W, alt. 339m, humid zone, on bark, 22-Jan-2011, Bungartz 10051 (CDS 47446); caldera of Cerro Pajas, old trail in the caldera, 1°17’48”S, 90°27’21”W, humid zone, on bark 02-Jan-2010, Hillmann GAL-13, 28, 33, 38, 40, 46, 49, 51, 53, 57 (CDS 44776, 44853, 44796, 44801, 44803, 44793, 44852, 44816, 44818, 44827). Isla Pinta, along the trail up to the summit from the S-coast, 0°34’31”N, 90°45’6”W, alt. 388m, humid zone, on bark, 27-Feb-2007, Bungartz 5844 (CDS 33519); 0°34’57”N, 90°45’11”W, alt. 579m, humid zone, on bark, 26-Feb-2007, Bungartz 5766 (CDS 33438); 0°34’39”N, 90°45’7”W, alt. 436m, humid zone, on bark, 27-Feb-2007, Bungartz 5806 (CDS 33479). Isla Pinzón, E-facing side of a valley on the W-slope of the highest mountain, 0°36’49”S, 90°40’14”W, alt. 294m, transition zone, on bark, 16-Feb-2006, Bungartz 3650 (CDS 27468). Isla San Cristóbal, W of the cemetery of El Progresso at the border of the National Park, 0°54’45”S, 89°34’34”W, alt. 170m, transition zone, on bark, 24-Aug-2008, Bungartz 8559 (CDS 41205); El Chino in the southern higher part of the island, 0°54’42”S, 89°27’15”W, alt. 220m, humid zone, agricultural area, on bark, 29-Apr-2007, Bungartz 6771 (CDS 35022). Isla Santa Cruz, 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, humid zone, on bark of Cedrela, 19-Feb-2006, Aptroot 64322 B (CDS 44663), Aptroot 64329 (CDS 30894), Aptroot 64322 A (CDS 30887); above the quarry Mina Granillo Rojo, off the main road to the channel, on the N-side of the island, 0°37’6”S, 90°21’59”W, alt. 617m, transition zone, on bark, 21-Oct-2007, Ertz, D. 11601 (CDS 36927). Isla Isabela, Volcán Alcedo, outer SE-exposed slope, ca. 2.5 km below the crater rim, 0°26’13”S, 91°4’33”W, alt. 785m, transition zone, on bark, 07-Mar-2006, Bungartz 4254 (CDS 28324), Bungartz 4239 (CDS 28309); Bungartz 4255 (CDS 28325); plain at the base of the outer E-exposed slope, along the trail going up to the rim, 0°24’47”S, 91°4’12”W, alt. 768m, transition zone, on bark, 08-Mar-2006, Bungartz 4314 (CDS 28388), Aptroot 64866 (CDS 31443); Volcán Cerro Azul, along the trail from Caleta Iguana to the first Caseta del Parque, 0°59’14”S, 91°25’39”W, alt. 300m, transition zone, on bark, 03-May-2012, Bungartz 10307 (CDS 52280), Bungartz 10309 (CDS 52282); lower half of path from the Caseta del Parque to Caleta Iguana, 0°58’52”S, 91°26’41”W, alt. 74m, dry zone, on wood, 09-May-2012, Bungartz 10478 (CDS 52440); path from the fist Caseta del Parque to Caleta Iguana, approx. a third of the way, 0°59’10”S, 91°26’5”W, alt. 224m, transition zone, on bark, 07-May-2012, Spielmann 10641 (CDS 52008).

from:
Bungartz, F., Dútan, V. & Elix, J.A. (2013) The lichen genera Cryptothecia, Herpothallon and Helminthocarpon (Arthoniales) in the Galapagos Islands, Ecuador. The Lichenologist 45(6): 1–24.