Flavoparmelia gerlachei (Zahlbr.) Hale (1986: 604)

Elvebakk, A., Bjerke, J. W. & Støvern, L. E., 2014, Parmelioid lichens (Parmeliaceae) in southernmost South America, Phytotaxa 173 (1), pp. 1-30 : 4-7

Flavoparmelia gerlachei (Zahlbr.) Hale (1986: 604)

Flavoparmelia gerlachei has been found by us to be very common and dominant on strongly exposed rocks in the steppe zone in the study area. The species has been confused with what is here described as Xanthoparmelia austrosorediata , but differs in its rotund and rather broad lobe apices which lack the strongly glossy surface and the dark-pigmented margin of X. austrosorediata , where lobe apices are more or less truncate (Figs. 2−4). These two species are also chemically distinct, with physodalic and malonprotocetraric acids in the former and protocetraric acid in X. austrosorediata , both in addition to usnic acid. All TLC spots of the suspected protocetraric acid of F. gerlachei were systematically in positions below protocetraric acid references, with R f values of 2 vs. 3 in solvent A and 4 vs. 5 in solvent C, respectively. These values correspond exactly with those of malonprotocetraric acid as described from a Parmotrema species by Keogh (1977) and Huneck & Yoshimura (1996), and is determined here as this substance, although no reference has been available.

The species was reported with one locality from Magallanes and one from Santa Cruz in addition to localities in Antarctica and Venezuela by Hale (1986). Hale (1986) cited its chemistry as protocetraric and usnic acids in his own collections from Venezeula, which makes us believe that these collections are either X. austrosorediatum or another species. The two cited samples from Chile and Argentina contain physodalic, protocetraric and usnic acid, a chemotype also reported later from Santa Cruz and Argentinian Tierra del Fuego by Calvelo & Adler (1999). Hale (1986) also cited the species to contain physodalic and usnic acids, which obviously would refer to his cited Antarctic specimens. This agrees with Øvstedal & Smith (2001), who studied numerous specimens from Antarctica and only reported on a chemotype with physodalic and usnic acids. The 11 collections studied by TLC here all have physodalic and malonprotocetraric acids in addition to usnic acid.

FIGURE. Flavoparmelia gerlachei photographed at Morro Chico, Chile. FIGURE. Xanthoparmelia austrosorediata (left) and Flavoparmelia gerlachei (right) photographed at Morro Chico.

Here, Flavoparmelia gerlachei is reported as fertile for the first time, and apothecia were found in the collections Elvebakk 13:081 and 14:030, collected c. 100 m apart on the southern side of Morro Chico (Fig. 4). The apothecia are scattered, substipitate, 1−2.5 mm across, and urn-shaped with concave chestnut-brown discs. The thalline excipuli are conspicuously broad, c. 0.5 mm as seen from above, and sorediate in all mature apothecia. The ascospores are short- ellipsoid with proper ascospores 6−8.5 × 12.5−14 µm, surrounded by perispores 6.5−9.5 × 13.5−15 µm. The perispore is 0.5−1 µm thick, smooth in immature spores, verruculose in at least some of mature spores. A single spore has an apical perispore extension. The spores are a bit shorter and the perispore thinner than generally cited for Flavoparmelia by Hale (1986;>15 µm long and c. 2 µm thick, respectively).

FIGURE. A fertile specimen of Flavoparmelia gerlachei (Elvebakk 13:081) photographed at Morro Chico.

It is striking that the apothecia have only been found in a site where the species obviously has its optimum, at the lowermost part of the cool, vertical basalt cliff, obviously strongly manured by dust, and where the lichen vegetation is strongly similar to the one of an Antarctic bird-cliff (Fig. 5).

FIGURE. The S-facing basalt cliff wall of Morro Chico, dominated by Haematomma erythromma , Ramalina terebrata and Usnea acromelaena .

Specimens examined: ARGENTINA. PROVINCIA DE TIERRA DEL FUEGO; Sierra Alvear , the southern slope, c. 650 m, on exposed rocks in the alpine region, 9 Feb 1940, Santesson, R. 884 (S) ; CHILE. XII REGIÓN DE MAGALLANES: Sierra Baguales , 1 km N of Estancia Las Tres Erres , 50 ° 45’39”S, 72 ° 24’52”W, on soft sandstones in a steppe landscape, 5 Dec 1999, Elvebakk, A. 99:1156 ( TROM) ; 14:020 ( TROM); 3–4 km S of Estancia Las Tres Erres , 50 ° 48’S, 72 ° 25’W, 250 m, rocks in a steppe landscape, 5 Dec 1999, Elvebakk, A. 99:1162 ( TROM) ; 1.3 km S of the junction between the roads towards Las Chimas and Las Cumbres , 50 ° 53’S, 72 ° 23’W, 2−300 m, on an erratic boulder in a steppe landscape, 5 Dec 1999, Elvebakk, A. 99:1145 ( TROM) ; Parque Nacional Torres del Paine , 1.5 km N of Laguna Blanquillos , on the most exposed parts of rock outcrops or exposed boulders, 1 Jan 2014, Elvebakk, A. 14:014 ( TROM) ; 14:015 ( TROM); 3−400 m SE of Laguna Los Flamencos , 51 ° 02’S, 72 ° 48’W. on the top of exposed boulders, 2 Dec 1999, Elvebakk, A. 99:1013 ( TROM) ; Lago Nordenskjöld S, 1 km W of the Miradór , 51 ° 02’30”S, 72 ° 56’W, 70 m, on shaded rocks, 1 Dec 2000, Elvebakk, A. 00:860 ( TROM) ; 100 m N of Salto Grande , 51 ° 03’57.3”S, 73 ° 00’25.7”W, 80 m, on a light-exposed rock, 3 Dec 1999, Elvebakk, A. 99:1022 ( TROM) ; 1 km W of Guardería Lago Grey , 51 07’30”S, 73 10’30”W, 80 m, on light-exposed open rocks near the river, 4 Dec 1999, Elvebakk, A. 99:1098A ( TROM) ; Morro Chico , on strongly dust-manured, vertical cliff, 30 Dec 2013, Elvebakk, A. 13:074 ( TROM) ; 13:076 ( TROM); 13:081 ( MAF; TROM); 28 Nov. 1999, Elvebakk, A. 99:819 ( TROM) .