Lichens of Gomera (Flechten Gomeras)

	Between 1999 and 2019 I have visited La Gomera for eighteen times in order to photograph, to collect and to identify lichens. This results in ca. 1500 collections (capsules). Most of them are deposited in the Natural History Museum in Stuttgart (STU) - with the exception of those from 2018 and 2019. The latter are presented here gradually. The numbers in parentheses are my (provisional) herbar numbers. If there is a date instead of a herbarium number (for example, 180530), then there exists a photo only. The collection from 2018/19 will be deposited in the herbarium of the University of Tenerife.
	Photos with an * were made in La Gomera. More (earlier) lichen photos of La Gomera can be seen in my Lichen Gallery.
Copyright: Ulrich Kirschbaum

Recent edition: September 2020

(Proposals for corrections are desired).

Flechtenbilder (A-F)

	Anaptychia ciliaris * (L.) Körber (266) On volcanic rocks. Lobes tomentose, long, narrow (up to 2.5 mm wide), widening at the ends; with long, marginal cilia; lower surface concave, white (upper surface: grey to brownish); apothecia on short stalks, discs black, pruinose. Spot reactions negative. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Anaptychia ciliaris * (L.) Körber (266) On volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Anaptychia ciliaris * (L.) Körber (266) On volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Athallia pyracea * (Ach.) Arup, Frödén & Søchting (358) (Caloplaca pyracea). On Ilex canariensis. Thallus grey, inconspicuous or endosubstratic; apothecia zeorine ((marginlecanorine and biatorine) up to 1 mm diam.; proper margin +- paler than disc; thalline margin yellow, poorly developed; epithecium orange-brown, granular, hymenium colourless (88 µm); hypothecium colourless; asci 8- spored; ascospores polarilocular (14.7 - 16.5 x 7.7 - 10.5 µm); septum broad (7.0-9.8 µm). Thallus K-; apothecia K+ red. E; La Gomera-MN; s of Las Rosas; s of Roque Blanco: near Mirador Dinero.
	Athallia pyracea (Ach.) Arup, Frödén & Søchting (358) On Ilex canariensis. E; La Gomera-MN; s of Las Rosas; s of Roque Blanco: near Mirador Dinero.
	Athallia pyracea (Ach.) Arup, Frödén & Søchting (358) On Ilex canariensis. E; La Gomera-MN; s of Las Rosas; s of Roque Blanco: near Mirador Dinero.
	Athallia pyracea (Ach.) Arup, Frödén & Søchting (358) On Ilex canariensis. E; La Gomera-MN; s of Las Rosas; s of Roque Blanco: near Mirador Dinero.
	Athallia pyracea (Ach.) Arup, Frödén & Søchting (358) On Ilex canariensis. Microscopic details. E; La Gomera-MN; s of Las Rosas; s of Roque Blanco: near Mirador Dinero.
	Blastenia crenularia (With.) Arup, Søchting & Frödén (251) (Caloplaca crenularia). On base-rich volcanic rocks. Thallus grey, areolate; apothecia up to 1 mm diam., often undulate; disc flat (convex with age); margin prominent (disappearing with age); epithecium brown; hymenium colourless (- 80 µm); hypothecium colourl.; ascospores (8 per ascus), polarilocular, colourl., 11.9-14.4 x 6.3-7.0 µm; septum wide (6.3-7.0 µm); paraphyses unbranched. Thallus K+- violet, C-; apothecia K+ red; apothecial rim C+ red. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Blastenia crenularia (With.) Arup, Søchting & Frödén (251) (Caloplaca crenularia) E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Blastenia crenularia (With.) Arup, Søchting & Frödén (251) (Caloplaca crenularia). Spot tests. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Blastenia crenularia (With.) Arup, Søchting & Frödén (265) (Caloplaca crenularia) On a nw-exposed terrace wall of volcanic rocks. E; Canary Islands; La Gomera-MW: n of Arure.
	Caloplaca haematites (Chaub. ex St.-Amans) Zwackh. (35) On twigs of dead Cistus monspeliensis. Thallus consisting of dark grey, uneven areoles; apothecia up to 4 mm diam., +- constricted at base; disc sanguine (gr. haima = blood), concave to flat (when older); margin paler grey than thallus, smooth, swollen; hymenium colourless (50 µm); asci (40 µm), 8-spored; ascospores polarilocular, ellipsoidal (11.9-14.7 x 7.0-9.1 µm); septum wide (4.2-6.3 µm). Thallus K-; disc K+ red. E; Canary Islands; La Gomera-M; e of Chipude: n of Fortaleza. New for La Gomera!
	Caloplaca haematites (Chaub. ex St.-Amans) Zwackh. (35) On twigs of dead Cistus monspeliensis. Thallus K-; disc K+ red. E; Canary Islands; La Gomera-M; e of Chipude: n of Fortaleza.
	Caloplaca haematites (Chaub. ex St.-Amans) Zwackh. (35) On twigs of dead Cistus monspeliensis. Apothecial disc sometimes black. E; Canary Islands; La Gomera-M; e of Chipude: n of Fortaleza.
	Caloplaca haematites (Chaub. ex St.-Amans) Zwackh. (35) On twigs of dead Cistus monspeliensis. Microscopic details. E; Canary Islands; La Gomera-M; e of Chipude: n of Fortaleza.

	Caloplaca teicholyta (Ach.) Steiner (330) On a concrete wall. Thallus +- placodioid; lobe ends often indistinct, slightly convex; center of the thallus consisting of granules; coarsely sorediate. Thallus K-. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Caloplaca tenuata * (Nyl.) Zahlbr. (23) (Often confused with C. polycarpa; syn. Flavoplaca polycarpa) On volcanic rocks. Thallus crustose-placodioid, yellow-orange, lobed at margin, lobes short, slightly convex; apothecia (-0.8 mm); disc bright orange; proper margin paler; epithecium orange-brownish; hymenium colourless (77 µm); hypothecium colourless; asci 8-spored (-53 µm); ascospores 1-septate, polarilocular, colourless, long-ellipsoid to spindle-shaped, +- curved (18-21 x 5-7 µm), septum 3-4 µm thick (ca. ¼ of the ascospore length). Photobiont chlorococcoid. Thallus and apothecia K+ red. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Caloplaca tenuata * (Nyl.) Zahlbr. (23) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Caloplaca tenuata (Nyl.) Zahlbr. (23) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Caloplaca tenuata (Nyl.) Zahlbr. (23) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Caloplaca tenuata (Nyl.) Zahlbr. (23) On volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Cladonia foliacea (Huds.) Willd. (36) On non calcareous soil. Thalline squamules yellowish-green on upper side, recurved and deeply incised on the tips; lower side can be seen because of the curled squamules, whitish-yellowish; podetia not seen. Thallus K-, KC+ yellowish, Pd+ orange-red. E; Canary Islands; La Gomera-M; e of Chipude: Top of the Fortaleza.
	Cladonia foliacea (Huds.) Willd. (36) On non calcareous soil. Spot tests. E; Canary Islands; La Gomera-M; e of Chipude: Top of the Fortaleza.
	Cladonia humilis (With.) Laundon (30) On soil. Podetia very small (up to 5 mm tall, scyphi up to 2.5 mm wide), ecorticate (but with a small basal corticate zone); margin of the scyphi not proliferating, but with dentate pycnidia/apothecia; inside with granular soredia; basal squamules relatively large (up to 1.9 mm wide), upper surface greenish, corticate, lower side white, ecorticate. Thallus K+ yellow, Pd+ orange-red. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Cladonia humilis (With.) Laundon (30) On soil. Application with K and Pd. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Cladonia rangiformis * Hoffm. (28/29) On mossy soil. Podetia corticate, branches widely divergent, loosely attached and dying from the base, +- isotomic and dichotomous, up to 3-4 cm tall; with (few) squamules; axils closed; algal layer areolate (older branches mottled); pycnidia brown, at tips of branches, frequent. Podetia K+ pale yellow, Pd-. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Cladonia rangiformis Hoffm. (28/29) On mossy soil. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Cladonia rangiformis Hoffm. (28/29) On mossy soil. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Cladonia rangiformis Hoffm. (28/29) On mossy soil. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.


	Dermatocarpon miniatum (L.) Mann (190317) On volcanic rocks. Thallus resembles to Umbilicaria (attached by a solitary holdfast), mostly single-lobed, up to 7 cm wide, concave but margins raised; margins usually deeply incised and contorted; perithecia small (-0.3 mm) with dark brown ostioles (Umbilicaria without perithecia); lower surface tan-brown. No spot reactions. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Diploschistes scruposus (Schreb.) Norman (50) Onvolcanic rocks (terrace wall). Thallus grey, areolate, warted-uneven; apothecia frequent, urceolate, disc pruinose, up to 2 mm, margin raised above the thallus. Cortex K± yellow, C+ red. E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.

	Flavoplaca oasis (A. Massal.) Arup, Frödén & Søchting (330) (Caloplaca oasis). On a concrete wall. Thallus indisctinct, consisting of small irregular, yellowish spots; apothecia small (up to 0.5 mm diam.); margin lighter than disc; epithecium orange-brown; hymenium colourless (55 µm); hypothecium colourless; asci 8-spored (46 µm); ascospores polarilocular, broad ellipsoid (9.8-12.6 x 5.3-7.0 µm); septum3.5-4.2 µm). All yellow parts K+ red. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Flavoplaca oasis (A. Massal.) Arup, Frödén & Søchting (330) (Caloplaca oasis). On a concrete wall. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Flavoplaca oasis (A. Massal.) Arup, Frödén & Søchting (330) (Caloplaca oasis). On a concrete wall. Microscopic details. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.

Flechtenbilder (G-L)



	Gyalolechia canariensis (Follmann & Poelt) Søchting, Frödén & Arup (20) (Fulgensia canariensis; Caloplaca canariensis). On strongly eroded volcanic rocks. Thallus crustose, consisting of yellow areoles/squamules, surface smooth; apothecia up to 1 mm diam.; disc flat to slightly convex with age; margin lecanorine; epith. orange-brown; hymenium colourless (88 µm); hypoth. colourless; asci 8-spored (53 µm); ascospores simple to 1-septate, pyriform (14.4-18.2 x 6.3-7.4 µm), conidia bacilliform; photobiont chlorococcoid. Thalllus and apothecia K+ red. E; Canary Islands; La Gomera-S ; nne of Santiago: hiking path between El Rumbazo and Targa.
	Gyalolechia canariensis (Follmann & Poelt) Søchting, Frödén & Arup (20) On strongly eroded volcanic rocks. E; Canary Islands; La Gomera-S ; nne of Santiago: hiking path between El Rumbazo and Targa.
	Gyalolechia canariensis (Follmann & Poelt) Søchting, Frödén & Arup (20) On strongly eroded volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-S ; nne of Santiago: hiking path between El Rumbazo and Targa.
	Gyalolechia canariensis (Follmann & Poelt) Søchting, Frödén & Arup (38) On strongly eroded volcanic rocks. E; Canary Islands; La Gomera-MSW; se of Chipude: at Fortaleza.
	Gyalolechia canariensis (Follmann & Poelt) Søchting, Frödén & Arup (38) E; Canary Islands; La Gomera-MSW; se of Chipude: at Fortaleza.
	Gyalolechia canariensis (Follmann & Poelt) Søchting, Frödén & Arup (38) On strongly eroded volcanic rocks. E; Canary Islands; La Gomera-MSW; se of Chipude: at Fortaleza.
	Gyalolechia canariensis (Follmann & Poelt) Søchting, Frödén & Arup (278) On volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Gyalolechia canariensis (Follmann & Poelt) Søchting, Frödén & Arup (278) On volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.


	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (250) (Caloplaca flavovirescens). On base-rich volcanic rocks. Thallus pale (greenish) yellow, dispersed; apothecia up to 1.5 mm diam.; apothecial disc orange (giving the lichen a bicoloured appearance), convex when older; margin paler, soon disappearing; epithecium orange-brown; hymenium colourless (-65 µm); ascospores ellipsoid, colourless, polarilocular (12.3-14.0 x 7.0-7.7 µm); septum thick (5.3-6.0 µm). Thallus & apothecia K+ red. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (304) (Caloplaca flavovirescens). On volcanic rocks. Thallus consisting of (greenish)-yellow areoles, whitish pruinose; apothecia (-0.7 mm diam.); disc deep orange, flat, later convex; thalline margin yellow-grey; proper margin orange; epith./hypoth. colourless; hymenium colourless (-60 µm); asci 8-spored (-50 µm); ascospores colourless, polarilocular (12.6 - 14.0 x 6.3 - 7.7 µm); septum (3.5-5.3 µm). All parts K+ red. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (304) On volcanic rocks. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (304) On volcanic rocks. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (304) On volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (329) On volcanic rocks. Thallus consisting of (greenish)-yellow areoles, whitish pruinose; apothecia (-1.2 mm diam.); disc deep orange, flat; thalline margin concolourous with thallus; proper margin orange; epith./hypoth. colourless; hymenium colourless (-53 µm); asci 8-spored; ascospores colourless, polarilocular (16.1 - 18.2 x 7.7 - 9.1 µm); septum (7.0-8.8 µm). All parts K+ red. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (329) On volcanic rocks. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (329) On volcanic rocks. Application with K. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Gyalolechia flavovirescens (Wulfen) Søchting, Frödén & Arup (329) On volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Gyalolechia subbracteata (Nyl.) Søchting, Frödén & Arup (18) On calcareous soil. Thallus clearly lobate at the margins (but lobes shorter and more adnate than at G. fulgens); pruinose; usually without apothecia; the similar G. bracteata is not lobate and has usually many apothecia); with many scaly schizidia. Thallus K+ red. E; Canary Islands; La Gomera-NW: Village of Epina.
	Gyalolechia subbracteata (Nyl.) Søchting, Frödén & Arup (33) On calcareous soil. Thallus clearly lobate at the margins (but lobes shorter and more adnate than at G. fulgens); pruinose; usually without apothecia; apothecial disc flat; margin lecanorine; with many scaly schizidia; (the similar G. bracteata is not lobate and has usually many apothecia). Thallus and apothecia K+ red. E; Canary Islands; La Gomera-NNW: hiking path between Playa de Vallehermoso and M. Alcala (Buenavista).
	Gyalolechia subbracteata (Nyl.) Søchting, Frödén & Arup (33) On calcareous soil. E; Canary Islands; La Gomera-NNW: hiking path between Playa de Vallehermoso and M. Alcala (Buenavista).
	Lecanora muralis * (Schreb.) Rabenh. (25) On volcanic rocks. Thallus placodioid, pruinose; maginal lobes +- appressed; center sometimes areolate; apothecia up to 1.5 mm diam.; disc yellowish brown, without pruina; margin lecanorine, pruinose; ascospores colourless, simple, ellipsoid (10.5-14.0x6.7-7.4 µm). E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Lecanora muralis * (Schreb.) Rabenh. (25) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Lecanora muralis (Schreb.) Rabenh. (25) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Lecanora muralis (Schreb.) Rabenh. (25) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Lecanora muralis (Schreb.) Rabenh. (25) On volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.

	Lecanora rupicola (L.) Zahlbr. subsp. rupicola (45) On volcanic rocks. Thallus thick, deeply cracked-areolate; areoles flat, containing one or two apothecia; apothecia subimmersed, up to 1,5 mm diam.; disc flat to slightly convex, black, pruinose; margin concolorous with thallus (lecanorine); epithecium olive-green; hymenium colourless (50 µm); hypothecium colourless; ascospores simple, colourless, elliptical (10.5-13.3 x 6.3-7.7 µm); photobiont trebouxioid. Thallus K+ yellow, C-, KC-, Pd+ yellow (atranorin, chloratranorin); apothecial disc (pruina) C+ yellow. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata). New to La Gomera.
	Lecanora rupicola (L.) Zahlbr. subsp. rupicola (45) On volcanic rocks. Thallus K+ yellow, Pd+ yellow. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Lecanora rupicola (L.) Zahlbr. subsp. rupicola (45) On volcanic rocks. Apothecial disc C+ yellow. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Lecanora rupicola (L.) Zahlbr. subsp. rupicola (45) On volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).

	Lecanora sulphurella * Hepp (180411) On volcanic rocks. Thallus consisting of areoles, grey to bright yellow; apothecial disc black; margin persistent, of the colour of the thallus (lecanorine). E; Canary Islands; La Gomera-SW; ssw of Chipude: Ermita N.S. de Guadalupe.
	Lecanora sulphurella * Hepp (180411) On volcanic rocks. E; Canary Islands; La Gomera-SW; ssw of Chipude: Ermita N.S. de Guadalupe.

	Lobaria macaronesica Cornejo & Scheidegger (16) Corticolous; on Laurus novocanariensis. Lobes with depressions and reticulately ridged; without soralia; with true, cylindric isidia (arising directely from the upper surface: completely corticate; see lower image). Medulla K+ yellow to red, C-, Pd+ yellow. (The similar L. pulmonaria has soralia, sometimes growing into untrue isidia. L. immixta is not sorediate, isidia are marginal and flat; medulla C+ red). E; Canary Islands; La Gomera-NW; n of the Bar Epina: surroundings of the large antenna.
	Lobaria macaronesica Cornejo & Scheidegger (16) Corticolous; on Laurus novocanariensis. E; Canary Islands; La Gomera-NW; n of the Bar Epina: surroundings of the large antenna.

Flechtenbilder (M-P)


	Nephroma tangeriense * (Maheu &. A. Gillet) Zahlbr. (31) On soil. Lobes with marginal and laminal folioles; medulla yellow. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Nephroma tangeriense (Maheu &. A. Gillet) Zahlbr. (31) On soil. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Nephroma tangeriense (Maheu &. A. Gillet) Zahlbr. (31) On soil. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.

	Ochrolechia pallescens * (L.) A. Massal. (180406) Corticolous; on Laurus novocanariensis. Thallus grey, granular warted, not sorediate; apothecia numerous, evenly scattered, margins thick (sometimes covering the disc), smooth, entire, discs yellowish-brown, flat with age, up to 2 mm. Thallus K-, KC+ yellow, Pd-; apothecial disc KC+ red. The very similar O. parella is saxicolous. E; Canary Islands; La Gomera-NW; n of the Bar Epina: hiking path between the large antenna and Ermita Santa Clara.

	Parmelia saxatilis (L.) Ach. (42) On volcanic rocks. Lobes ridged; pseudocyphella forming a reticulate net (mainly near the tips); isidia cylindrical to coralloid, sometimes covering the whole center. Cortex K+ yellow; medulla K+ yellow becoming orange to red, Pd+ yellow and then orange-red The very similar P. ernstiae is lobulate, strongly pruinose and corticolous. Distincted from P. sulcata and P. omphalodes by the presence of isidia. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Parmelia saxatilis (L.) Ach. (42) On volcanic rocks. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Parmelia saxatilis (L.) Ach. (42) On volcanic rocks. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).

	Parmotrema reticulatum * (Taylor) Choisy (31) On volcanic rocks. Upper surface with a faint network of white pseudocyphellae. Soralia mainly at margins or tips of the lobes; lobe margins with black cilia; lower surface without rhizines (naked) along margins. Cortex K+ yellow, medulla Pd+ orange-red. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.
	Parmotrema reticulatum (Taylor) Choisy (31) On volcanic rocks. E; Canary Islands; La Gomera-NW; s of Vallehermoso: Camino Forestal de la Meseta.

	Physcia adscendens (Fr.) Oliv. (51) On twigs of dead Cistus monspeliensis. Lobes with marginal cilia; lobe ends raised, helmet-like (difference to P. tenella); soralia on the lower side of the helmets; upper surface with pseudocyphellae (better visible when wet). Cortex K+ yellow, medulla K-. E; Canary Islands; La Gomera-M; e of Chipude: n of Fortaleza.
	Physcia caesia * (Hoffm.) Fürnr. (190317) On nutrient-enriched volcanic rocks. Lobe surface blue-grey; with convex soralia (usually laminal). Cortex, medulla K+ yellow. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Physcia caesia * (Hoffm.) Fürnr. (190317) On nutrient-enriched volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Physcia tribacia * (Ach.) Nyl. (22) On volcanic rocks. Thallus irregular, consisting of +- appressed lobes, lobe ends sometimes faintly pruinose, margins with crenulations, tips +- granular sorediate; sometimes lip-shaped; lower cortex of the lobes pseudoparenchymatous (see lowest photo); apothecia very rare (up to 1 mm diam.), disc flat, margin lecanorine. Cortex K+ yellow. Distinguished from the very similar (and common) P. dubia by absence of white spots on the upper surface. The latter has a prosoplectenchymatous lower cortex. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Physcia tribacia (Ach.) Nyl. (22) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Physcia tribacia (Ach.) Nyl. (22) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Physcia tribacia (Ach.) Nyl. (22) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Physcia tribacia (Ach.) Nyl. (22) On volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Placidium squamulosum * (Ach.) Breuss (275) On nutrient-enriched volcanic rocks. Thallus consisting of adpressed squamules, up to 5 mm in diameter; perithecia hemisperical. No spot reactions. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Placidium squamulosum * (Ach.) Breuss (275) On nutrient-enriched volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.

	Pseudocyphellaria aurata (Ach.) Vainio (15) On Laurus canariensis. Granular soralia and pseudocyphellae (lower side) golden yellow (Pseucocyphellaria crocata with white pseudocyphellae); apothecia rare, +- stalked; disc concave to plane, brown; margin with yellow soralia; lower surface tomentose. E; Canary Islands; La Gomera-NW; n of the Bar Epina: surrounding of the large antenna.
	Pseudocyphellaria aurata (Ach.) Vainio (15) On Laurus canariensis. E; Canary Islands; La Gomera-NW; n of the Bar Epina: surrounding of the large antenna.
	Pseudocyphellaria aurata (Ach.) Vainio (15) On Laurus canariensis. Lower side. E; Canary Islands; La Gomera-NW; n of the Bar Epina: surrounding of the large antenna.

Flechtenbilder (R-Z)


	Ramalina decipiens Mont. (47) On volcanic rocks (terrace wall). Thallus 5.5 cm long; lobes up to 5 mm wide, occasionally branched, ± flat, often longitudinally striated; pseudocyphellae inconspicuous; isidia and soralia absent; apothecial disc concave; margin crenate; pycnidia common, marginal, laminal and terminal, ostioles black. Thallus K+ red, Pd+ orange. E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina decipiens Mont. (47) On volcanic rocks (terrace wall). E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina decipiens Mont. (47) On volcanic rocks (terrace wall). E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina decipiens Mont. (47) On volcanic rocks (terrace wall). Spot tests with K and Pd. E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina requienii * (De Not.) Jatta (48) On volcanic rocks (terrace wall). Thallus up to 3 cm, brownish near the base; lobes solid, flat, subterete near apice, up to 5 mm broad, ends finely divided; granular soralia marginal or with coarse, corticate granules (photos 5/6); apothecia rare, lateral (photo 4). Thallus K-, Pd-. E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina requienii (De Not.) Jatta (48) On volcanic rocks (terrace wall). E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina requienii (De Not.) Jatta (48) On volcanic rocks (terrace wall). E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina requienii (De Not.) Jatta (48) On volcanic rocks (terrace wall). E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina requienii (De Not.) Jatta (48) On volcanic rocks (terrace wall). E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina requienii (De Not.) Jatta (48) On volcanic rocks (terrace wall). E; Canary Islands; La Gomera-MW; hiking path between Las Hayas and El Cercado.
	Ramalina subfarinacea (Nyl. ex Cromb.) Nyl. (40) On volcanic rocks. Thallus up to 5 cm, erect, branched, resembling R. farinacea; lobes flattened; soralia marginal, well delimited, rounded or elliptical, concave to flat; with coars granular soredia, sometimes with projections (photo 4); apothecia rare, laminal marginal or subterminal (photo 5). Thallus K+- yellowish; soralia Pd+ orange (red). E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Ramalina subfarinacea (Nyl. ex Cromb.) Nyl. (40) On volcanic rocks. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Ramalina subfarinacea (Nyl. ex Cromb.) Nyl. (40) On volcanic rocks. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Ramalina subfarinacea (Nyl. ex Cromb.) Nyl. (40) On volcanic rocks. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Ramalina subfarinacea (Nyl. ex Cromb.) Nyl. (40) On volcanic rocks. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).

	Squamarina cartilaginea * (With.) P. James (273) On volcanic rocks. Thallus squamulose; squamules greenish yellow, thick, overlapping, pruinose (pruina mainly on the margins); lower surface dark; apothecia not very common, 3 mm diam, disc brownish to reddish brown; margin entire, often excluded with age. Medulla Pd+ yellow or Pd-. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Squamarina cartilaginea * (With.) P. James (273) On volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Squamarina lentigera * (Weber) Poelt (18) On calcareous soil. Thallus rosette-forming; squamules whitish to ochre, covered with a white pruina (especially at the thalline margins); margins turned upward; apothecia 1.5-2 mm diam.; thalline exciple entire, thick at first, later almost disappearing; proper exciple inconspicuous. No spot reactions. E; Canary Islands; La Gomera-NW: Village of Epina.
	Squamarina lentigera (Weber) Poelt (18) On calcareous soil. E; Canary Islands; La Gomera-NW: Village of Epina.
	Squamarina lentigera (Weber) Poelt (18) On calcareous soil. E; Canary Islands; La Gomera-NW: Village of Epina.
	Squamarina lentigera (Weber) Poelt (18) On calcareous soil. E; Canary Islands; La Gomera-NW: Village of Epina.
	Squamulea subsoluta (Nyl.) Arup, Søchting & Frödén (305) (Caloplaca s.; Caloplaca irrubescens). On basaltic rocks. Thallus consisting of small patches, areolate; apothecia up to 0.4 mm diam.; proper margin concolorous with disc, becoming excluded with age; epithecium orange-brown; hymenium colourless (42-53 µm); hypothecium colourless; ascospores polarilocular (11.6-14.7 x 6.3-8.4 µm); septum 3.5-5.0 µm. Thallus and apothecia K+ red. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Squamulea subsoluta (Nyl.) Arup, Søchting & Frödén (305) (Caloplaca s.; Caloplaca irrubescens). On basaltic rocks. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Squamulea subsoluta (Nyl.) Arup, Søchting & Frödén (305) (Caloplaca s.; Caloplaca irrubescens). On basaltic rocks. Microscopic details. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Stereocaulon dactylophyllum Flörke (41) On volcanic rocks. Thallus consisting of +- erect, +- terete pseudopodetia (-3.5 cm tall), solid, without tomentum; covered with numerous cylindrical to coralloid protuberances (phyllocladia), resembling to isidia with dark tips; without apothecia (usually numerous). Thallus K+ yellow (my first application showed reddish-brown colour; C-; KC-; Pd + yellow. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Stereocaulon dactylophyllum Flörke (41) On volcanic rocks. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Stereocaulon dactylophyllum Flörke (41) On volcanic rocks. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).
	Stereocaulon dactylophyllum Flörke (41) On volcanic rocks. Two spot tests with K and with Pd. E; Canary Islands; La Gomera-M; e of Chipude: Fortaleza (via ferrata).

	Sticta fuliginosa (Hoffm.) Ach (17) On Laurus novocanariensis. Thallus up to 5 cm diam., ± single-lobed; lobes rounded (to 3 cm wide); upper surface with scattered cylindrical to coralloid isidia; lower side brown, with conspicuous, rounded cyphellae. Spot tests negative. (Very similar is S. sylvatica, but the latter has uneven lobe margins and is more-lobed when mature). E; Canary Islands; La Gomera-NW; n of the Bar Epina: surrounding of the large antenna.
	Sticta fuliginosa (Hoffm.) Ach (17) On Laurus novocanariensis. Upper surface with corraloid isidia. E; Canary Islands; La Gomera-NW; n of the Bar Epina: surrounding of the large antenna.
	Sticta fuliginosa (Hoffm.) Ach (17) On Laurus novocanariensis. Lower surface with tomentum and cyphellae. E; Canary Islands; La Gomera-NW; n of the Bar Epina: surrounding of the large antenna.

	Teloschistes chrysophthalmus (L.) Th. Fr. On twigs of dead Cistus monspeliensis. Lobes flattened; upper surface yellow to grey-orange, lower surface paler; lobes with spinules; apothecia abundant, short stalked, margins with numerous spinules (resembles a golden eye). Thallus K+ red. E; Canary Islands; La Gomera-M; e of Chipude: n of Fortaleza.
	Teloschistes flavicans * (Sw.) Norm. (180405) On volcanic rocks. Thallus fructicose, richely branched; branches (0.5-1 mm) rounded, flattened or angled. Cortex K+ purple. E; Canary Islands; La Gomera-NW; n of the Bar Epina: hiking path between the large antenna and Ermita Santa Clara.
	Usnochroma scoriophila * (A. Massal.) Søchting, Arup & Frödén (Caloplaca scoriophila) (180411) On volcanic rocks. Thallus yellow-green, effigurated; apothecial disc orange-red, flat when young, later convex; margin lecanorine (concolorous with thallus); spores ellipsoid, polarilocular. Thallus KC+ (faintly red); apothecial disc K+ red. E; Canary Islands; La Gomera-SW; ssw of Chipude: Ermita N.S. de Guadalupe.

	Variospora spec. * (264) On a nw-exposed terrace wall of volcanic rocks (calcareous?). Thallus placodioid; lobes closely adpressed and flat to convex, rounded, slightly palmate, partly pruinose; apothecia up to 1 mm diam. epithecium orange-brown; hymenium colourless (-70 µm); hypothecium colourless; asci 8-spored (63 µm); ascospores colourless, polarilocular lemon-shaped to rhomboid in parts (13.7-14.7 x 7.0-7.4); septum 4-5 µm. Th. and apothecia K+ red. E; Canary Islands; La Gomera-MW: n of Arure.
	Variospora spec. * (264) On a nw-exposed terrace wall of volcanic rocks (calcareous?). E; Canary Islands; La Gomera-MW: n of Arure.
	Variospora spec. (264) On a nw-exposed terrace wall of volcanic rocks (calcareous?). E; Canary Islands; La Gomera-MW: n of Arure.
	Variospora spec. (264) On a nw-exposed terrace wall of volcanic rocks (calcareous?). E; Canary Islands; La Gomera-MW: n of Arure.
	Variospora spec. (264) On a nw-exposed terrace wall of volcanic rocks (calcareous?). Microscopic details. E; Canary Islands; La Gomera-MW: n of Arure.
	Variospora spec. * (306) On volcanic rocks. Thallus placodioid, but areolate in the center; lobes convex, pruinose; apothecia up to 1.5 mm diam.; +- confined to the center; disc flat, later convex; margin paler than disc, later disapperaring; epithecium orange-brown; hymenium colourless (70 µm), with oil droplets; hypothecium colourless; asci 8-spored; ascospores 1-septate; lemon-shaped (13.3 - 15.4 x 6.6 - 9.8 µm); septum > 3 µm; photobiont chlorococcoid. Thallus and apothecia K+ red. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Variospora spec. * (306) On volcanic rocks. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Variospora spec. (306) On volcanic rocks. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Variospora spec. (306) On volcanic rocks. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Variospora spec. (306) On volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-MW; nnw of Arure: hiking path to Alojera.
	Variospora spec. (331) On volcanic rocks. Thallus placodioid; lobes convex, pruinose; apothecia up to 1 mm diam.; +- confined to the center; disc flat; margin paler than disc; epithecium orange; hymenium colourless (60 µm), with oil droplets; hypothecium colourless; asci 8-spored (50 µm); ascospores 1-septate; lemon-shaped (15.8 - 17.9 x 7.0 - 8.1 µm); septum 2.1-2.8 µm; photobiont chlorococcoid. Thallus light purple; apothecia K+ red. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Variospora spec. (331) On volcanic rocks. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.
	Variospora spec. (331) On volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-NW; se of Vallehermoso: El Tion.

	Xanthocarpia crenulatella (Nyl.) Frödén, Arup & Søchting (277) (Calolplaca c.) On nutrient-enriched volcanic rocks. Thallus yellowish, crustose-areolate; apothecia (- 0.5 mm diam.); disc orange,+- flat; proper margin surrounded by a thalline rim; paraphyses unbranched, with 2 swollen tip cells; epithecium orange-brown; hymenium colourless (56 µm); hypothecium colourless; ascospores polarilocular (11.2 - 14.7 x 7.0 - 8.8 µm); septum 2.8-3.5 µm. All parts K+ red. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Xanthoc. crenulatella (Nyl.) Frödén, Arup & Søchting (277) On nutrient-enriched volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Xanthoc. crenulatella (Nyl.) Frödén, Arup & Søchting (277) On nutrient-enriched volcanic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Xanthoc. crenulatella (Nyl.) Frödén, Arup & Søchting (277) On nutrient-enriched volcanic rocks. Microscopic details. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Xanthoparmelia pulla * (Ach.) Blanco et al. (267) On volcanic rocks. Lobes shiny, smooth to wrinkled transversally near the center, with coars warts on the upper surface; lower side black (brown at the margin), with black rhizines; isidia and soralia absent; apothecia usually present, disc concave to flat, margin smooth. P. verruculifera is similar but isidia present and apothecia absent. Medulla: K-, C+ rose or -, KC+ red or - , P-. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Xanthoparmelia stenophylla (Ach.) Ahti & Hawksw. (268) On warm, well-lit silicatic rocks. Thallus yellow-green to yellow-grey; lobes up to 3 mm wide, +- shiny; no isidia (difference to the very similar X. conspersa); no soralia; lower side brown; apothecial disc brown; margin thin. Medulla K+ orange --> red, C-, Pd+ orange. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Xanthoparmelia stenophylla (Ach.) Ahti & Hawksw. (268) On warm, well-lit silicatic rocks. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Xanthoria aureola * (Ach.) Erichsen (190317) On volcanic rocks. Reminds on Xanthoria parietina but differs by the narrower (up to 2 mm wide), strap-like, often overlapping lobes and the mostly missing apothecia. Cortex K+ red. E; Canary Islands; La Gomera-MSW; ese of Chipude: hiking path between Fortaleza and Igualero; se of the little brook.
	Xanthoria calcicola * Oxner (24) On volcanic rocks. Like Xanthoria parietina but differs by the existence of knobby, irregularly globose or lobule-like isidia (often obscuring the center of the thallus) and the mostly missing apothecia. Cortex K+ red. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Xanthoria calcicola * Oxner (24) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Xanthoria calcicola Oxner (24) On volcanic rocks. E; Canary Islands; La Gomera-MS; e of Imada: El Azadoe.
	Xanthoria resendei * Poelt & Tav. (180406) On basaltic rocks. Thallus cartilaginous, orange with conspicuous yellowish maculae; lobes elongate, markedly convex, not overlapping. E; Canary Islands; La Gomera-NW; n of the Bar Epina: hiking path between the large antenna and Ermita Santa Clara.
	Xanthoria resendei * Poelt & Tav. (180406) On basaltic rocks. Thallus cartilaginous, orange with conspicuous yellowish maculae; lobes elongate, markedly convex, not overlapping. E; Canary Islands; La Gomera-NW; n of the Bar Epina: hiking path between the large antenna and Ermita Santa Clara.