Micarea magellanica (Müll. Arg.) Fryday
Biblioth. Lichenol. 88: 138. 2004.

Basionym: Patellaria magellanica Müll. Arg., Hedwigia 32: 129. 1893.—Bacidia magellanica (Müll. Arg.) Zahlbr., Cat. Lich. Univ. 4: 121. 1926.—Toninia magellanica (Müll. Arg.) Imshaug in sched.
Synonym: Micarea austroternaria Coppins & Kantvilas, Lichenologist 22: 277-9. 1990.


Description (from Coppins & Kantvilas 1990)
Thallus effuse, of scattered to contiguous areoles; prothallus innapparent. Areoles 80-300(-500) µm diam, convex to globose, grey-white and ±glossy, in exposed forms sometimes bluish-grey in upper parts; ecorticate, but with a hyaline epinecral layer up to c. 12 µm thick. Photobiont micaeoid, 4-7 µm diam., cephalodia absent or poorly differentiated (areoles often arise from a mixedd 'algal crust' that includes various cyanobacteria).
Apothecia numerous, (0.2-)0.3-0.8(-1.0) mm diam., or forming tuberculate clusters up to 1.4 mm diam., scattered or a few contiguous, at first plane and faintly marginate but usually soon convex, adnate or constricted below and ±turbinate, black, matt or slightly glossy; margin shallow and scarcely raised above the level of the disc, usually slightly more glossy than the disc. Hymenium 60-70 µm tall, dark aeruginose above ( especially in the epithecium), K-, N+ red, dilutely coloured below. Paraphyses numerous, slender, sparingly branched and anastomosed, 1.3-2 µm wide, apices not swollen or densely coated with pigment, although embedded in the amorphously pigmented epithecial gel. Asci clavate, 52-65 x 12-14 µm, 8-spored; in KI. with amyloid outer coat, and an amyloid apical dome with a shallow, conical chamber and a narrow apical cushion that widens towards the apical wall. Ascospores (10-)14-22 x (4-)4.5-5.5(-6) µm ellipsoid to usually fusiform, rarely slightly curved, (1-)3-septate. Hypothecium 200-350 µ tall, dilute aeruginose in upper part, becoming mottled olive-green or dull brown below, K-, N+ reddish; lower hymenium and upper hypothecium often with additional, scattered violet granules (K+ vivid aeruginose); hyphae vertically orientated in upper part intermixed with swollen (up to 5 µm wide), short-celled ascogenous hyphae. Excipulum well-developed, dilute aeruginose above, becoming hyaline below except for the green-brown outer edge, of radiating, branched hyphae, c. 1.5-2 µ wide.
Pycnidia rare, immersed in areoles, black, 30-50 µm diam.; wall green N+ red; conidia (microconidia) 6-7 x 0.8 µm, rod-shaped but with ±tapering ends

Chemistry. Kf+ yellow, Cf+ pink, KC+ orange-red, Pd+ deep yellow, UV- or whitish; alectorialic acid by TLC.

Ecology and distribution.

Notes: Micarea magellanica is a member of the M. assimilata group, which is characterized by a well-developed, areolate thallus, usually with cephalodia. It has 3-septate ascospores measuring 20-25 x 5-6 µm, and a thallus containing alectorialic acid. A similar species with shorter 3-septate ascospores and a thallus containing pannarin is described below as M. pannarica.
Micarea magellanica was previously known only from Chile and is here recorded for the first time from Argentina and New Zealand.
Micarea austroternaria Coppins & Kantvilas, described from Tasmanian and Chile, agrees with M. magellanica in all respects and is here included as a synonym.

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Thallus & apothecia


Apothecia


Spores, ascus and conidia