Lithographa olivacea
Holotype: New Zealand. Campbell I., summit and summit ridge of Mt Honey, 550 m, 31.xii.1969, R.C. Harris 4900 – MSC.
Description : Thallus crustose, areolate, 0.05–0.08 mm thick, olive-brown (pigmented region of cortex 10–12 μm thick, olivaceous, K+ brown, N+ pale-brown), usually in a mosaic of other crustose lichens. Prothallus black, visible between areolae and at margins. Medulla I+ weak violet. Apothecia immersed to sessile, lirellate, straight or slightly curved, 0.4–0.7 × 0.1–0.2 mm, but carbonised area of of exciple spreading onto adjacent areolae to 0.5 mm diam; margins raised and obscuring hymenium. Epithecium brown (K−, N−). Hymenium colourless to 70 μm tall, I+ blue. Paraphyses free, richly branched and anastomosing, slender, not moniliform, 1.0–1.5 μm thick, not swollen at apices. Hypothecium pale-brown. Asci cylindrical, 40–50 × 10–12 μm, Rimularia -type. Ascospores simple, hyaline, ellipsoidal with rounded ends, (9–)11–12 (–14) × 6–7(–8) μm. Pycnidia black, immersed, 0.05–0.08 mm diam. Conidia bacillar, 6–8 × 0.5–0.8 μm.
Chemistry : TLC−, all reactions negative.
A: (Mt Easton), C: (Mt Honey). On subalpine rocks occurring in mosaics of other crustose lichens including: Labyrintha implexa, Pertusaria spp., Placopsis spp., Rimularia maculata and Tremolecia atrata. Known also from southern Chile (Fryday 2004a).
Austral
Lithographa olivacea is characterised by: the saxicolous habit (subantarctic, subalpine rocks); lirellate apothecia with carbonised exciple; a pale-brown hypothecium; Rimularia -type asci; simple, colourless, ellipsoidal ascospores, 9–14 × 6–8 μm; black, immersed pycnidia; and bacillar conidia, 6–8 × 0.5–0.8 μm.
