Flora of New Zealand Series

Thallus dimorphic consisting of a squamulose, areolate or nodular-papillate primary thallus and erect or ± decumbent pseudopodetia. Pseudopodetia radiate and ± terete at first near base, becoming flattened, expanded and ± leaf-like above. Cortex horny, of strong, cartilaginous, nerve-like strands forming a ± netlike cylinder enclosing a rather loosely developed, medulla. Photobiont green, Trebouxia. Apothecia terminal, disc plane to convex, often developed only on one side (ventral) of the supporting pseudopodetium, marginate or immarginate and ± thickened below. Ascospores often difficult to find, 8 per ascus, simple, colourless, ellipsoid, clavate, straight or curved 7-10 × 2-3 µm. Pycnidia marginal on squamules of primary thallus, black, bottle-shaped or cylindrical, with a gaping apical ostiole.

Thysanothecium, a genus of 2 species, is included in the family Cladoniaceae but is possibly better accommodated in a family of its own. Described originally from Australia, and thought to be endemic there, it is now known from Japan, China, Java, New Caledonia and New Zealand [Galloway Nova Hedwigia 28: 499-513 (1977); Galloway and Bartlett Nova Hedwigia 36: 381-398 (1983)]. Both species occur in New Zealand.