Megalospora lopadioides
Description : Thallus pale grey to whitish, rather thick, cracked, wrinkled, without soredia or isidia. Apothecia prominent, 1 –2.5 mm diam., smaller when young, often regenerating into small clustered groups of apothecia; disc plane, brown to black, slightly glossy, epruinose; margins prominent, flexuous, black, glossy. Epithecium diffuse olive-green, 15–18 μm thick. Hymenium 90–160 μm tall, I+ dark-blue. Exciple olive-yellow or olive-brown; ectal exciple with a thin, aeruginose margin, and an orange-brown subhypothecium, K+ yellowish. Ascospores 1 per ascus, muriform with thin septa (lopadioides -type), 10–25 transverse septa and 5–8 vertical septa, 60–90 × 25–35 μm, outer wall to 1 μm thick, smooth, without a perispore. Pycnidia not seen.
Chemistry : K−, C−, KC−, PD+ orange; containing pannarin and zeorin.
C: (Azimuth Saddle), on rock outcrop in tussock–herbfield. First collected in New Zealand by Carol West in 1995 (West & Polly 1999). Known also from Tasmania where it is common and widespread in areas exceeding 1000 mm annual rainfall. It ranges there from lowland to alpine, occurring in cool-temperate rainforest on a wide range of trees and shrubs, and also in sheltered moist crevices on Precambrian rock outcrops in buttongrass moorland and alpine heathland (Kantvilas 1994d; McCarthy 2003c, 2006). It is the most commonly collected species of the Megalosporaceae in Tasmania and is undoubtedly more widespread in New Zealand.
Australasian
Illustrations : Sipman (1983: 45, fig. 6H; pl. 21C).
Megalospora lopadioides is characterised by: the saxicolous habit; the thick, whitish grey, esorediate thallus containing pannarin and zeorin; large apothecia up to 2.5 mm diam., with glossy black margins; and muriform ascospores, 60–90 × 25–35 μm, with thin septa, occurring singly in the ascus.
