Flora of New Zealand Series

Thallus caespitose, squamulose to compressed-lobate, in ± dense compact mats, closely appressed to substrate. Lobes small-foliose, squamulose or terete, subdichotomously branching, compressed, dark greyish-brown to blackish above, paler brown to tan below, often pruinose at lobe tips. Photobiont blue-green ? Scytonema. Medulla white, Apothecia lecideine, terminal with a thin, concolorous proper margin, disc black or brown. Ascospores 8 per ascus, colourless, ellipsoid, simple.

Siphulastrum [Jatta Boll. Soc. bot. ital. 24: 246-250 (1892)], included in the family Pannariaceae, is a genus of 4 species most common in subantarctic regions (Tierra del Fuego, Falkland Is, Macquarie I.) and in subalpine and alpine localities in southern New Zealand and the subantarctic islands, where it is found on peat, soil, stones or among bryophytes in open, exposed grasslands or fellfield. Two species occur in New Zealand.