Siphulastrum Mull.Arg.,
Type : Siphulastrum triste Müll.Arg.
Descriptions : Flora (1985: 526). See also Jørgensen & Galloway (1992b: 290–291).
Key
Siphulastrum, a genus of four species (Jørgensen 2003c, 2004e), is included in the family Pannariaceae (Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005). Species of Siphulastrum are characterised by small-squamulose thalli, often forming isidioid or subisidioid crusts; terpenoids, argopsin and norargopsin as medullary compounds; I+ red-brown hymenial reaction; and no amyloid structures in the ascus apex (Jørgensen 1998b: 534). Siphulastrum occurs mainly in exposed alpine grasslands among rock outcrops in fellfield habitats, and rarely on stumps of Nothofagus in subalpine bogs in subantarctic regions, Tierra del Fuego, Patagonia, the Falkland Is, South Georgia, Tasmania and southern New Zealand (Galloway 1985a: 526–527; Jørgensen & Galloway 1992b; Jørgensen 1998b; Øvstedal & Lewis Smith 2001). Two species occur in New Zealand.