Flora of New Zealand Series

=Leptogium menziesii var. fusisporum Malme, Ark. Bot. 19 (8): 27 (1924).

Description : Thallus broadly lobate, orbicular to spreading, 5–8 cm diam., distinctly bluish to bluish grey, not brownish, musicolous, terricolous or corticolous. Lobes broadly orbicular, 5–10(–15) mm wide, papery, margins entire, wavy, sometimes minutely lobulate. Upper surface smooth, not wrinkled, matt or shining, often ±maculate (×10 lens). Lower surface densely white-tomentose, often with a narrow, marginal, glabrous zone concolorous with upper surface or paler. Apothecia occasional to abundant and then closely crowded together, sessile to subpedicellate, round to irregular, 0.2–1.5 mm diam., disc matt, yellow-brown to red-brown, concave to plane to subconvex, proper exciple prominent, paler than disc to ±whitish, thalline exciple reduced to a few scattered lobules, concolorous with thallus, generally absent, rarely with short white, silky marginal hairs and longer basal hairs. Epithecium yellow-brown to 12.5 μm thick. Hymenium colourless, 110–130 μm tall. Hypothecium opaque, pale brownish. Ascospores broadly ellipsoidal with pointed apices, sometimes ±apiculate at one or both ends, submuriform, 4–6 (–8) transverse septa and 1–3 vertical septa, (20–)25–35(–40) × 8–12(–14) μm.

N: Wellington (Ohakune; Manawatu River). S: Nelson (Cobb Valley, Lake Rotoiti), Marlborough (Avon Valley), Canterbury (Godley Valley), Otago (Hidden Falls Stream, Taieri Ridge), Southland (McKinnon Pass, Spey River). C: Among bryophytes in shaded, high-humidity rainforest habitats from the central North I. to Fiordland and Campbell I., with an altitudinal range of 100–1320 m (map in Galloway 1999: 344, fig. 13). It is still poorly collected in New Zealand and its ecology here largely unknown. It is known also from high-rainfall areas of southern Chile (Jørgensen 1975; Galloway & Jørgensen 1995).

Austral.

Leptogium malmei is closely similar to L. menziesii, but is distinguished from it by the distinctive bluish colour (as in L. azureum), the sessile apothecia that are often produced in profusion, and have a very thin margin, and the larger, acuminate ascospores, 25–35(–40) × 8–12(–14) μm (Jørgensen 1975: 442–443; 1997a: 125; Galloway & Jørgensen 1995: 240–241). The New Zealand material studied shows some variation in spore size, with material from drier, eastern sites having spores that are slightly smaller (20–25 μm) than those from wetter, western sites, which have generally longer and slightly broader spores. The species has a fairly constant morphology and colour and is readily separated from P. menziesii, which has lobes that are brownish, especially at the margins, and which also does not produce either laminal or marginal isidia or phyllidia. The description of L. limbatum in Galloway (1985a: 253) refers to L. malmei as correctly pointed out by Verdon et al. (1996: 26).