Flora of New Zealand Series

≡Lichen demissum Rutstr., Sp. Pl. crypt. Suec.: 8 (1794).

Description : Flora (1985: 243).

Chemistry : TLC−, all reactions negative.

N: Gisborne (Mt Hikurangi). S: Otago (West Matukituki Valley, Old Woman Ra., Old Man Ra., Mt Maungatua, Flagstaff Hill, Swampy Summit). Apparently rare, on peaty subalpine soils or among mosses in alpine or subalpine habitats, and on dry, exposed soil hummocks in high-alpine tundra vegetation. It is a member of soil crust communities on acid soils and at the edges of snow banks in the Northern Hemisphere (Fryday 2001a, 2001b; Türk & Gärtner 2001). It has a circumboreal distribution in the Northern Hemisphere, where it is known from Great Britain, Europe, Scandinavia, Greenland, North America, Tibet, Siberia, China and Japan (Schneider 1980; Inoue 1988; Nimis 1993; Santesson 1993; Esslinger & Egan 1995; Wirth 1995; Hansen 1995; Fryday 2001a, 2001b; Brodo et al. 2001, Türk & Gärtner 2001; Coppins 2002b; Nimis & Martellos 2003; Obermayer 2004; Santesson et al. 2004).

Bipolar

Illustrations : Schneider (1980: 91, fig. 11; pl. 51 – as Lepidoma demissum); Wirth (1987: 259; 1995a: 527); Hertel & Rambold (1988: 299, fig. 14); Inoue (1988: 186, fig. 16E); Foucard (1990: pl. 215); Pietschmann (1990: 530, fig. 3); Hansen (1995: 101); Dobson (2000: 210; 2005: 240); Brodo et al. (2001: 395, pl. 443).

Lecidoma demissum is characterised by: the terricolous habit; the squamulose–areolate thallus; a black prothallus; immersed to adnate, discrete or confluent apothecia with red-brown to brown-black discs; a red-brown epithecium; a colourless I+blue hymenium 60–70 μm tall; a colourless hypothecium; thin-walled Porpidia -like asci (with a well-developed K/I+ pale-blue apical dome and a K/I+ dark-blue tubular structure and a distal ring at the base of the tholus); and simple, colourless, ±subglobose to ellipsoidal ascospores without a perispore.