Poeltidea Hertel & Hafellner
Type : Poeltidea perusta (Nyl.) Hertel & Hafellner [Lecidea perusta Nyl.]
Description : Thallus crustose, areolate; areolae contiguous or separated by cracks, dispersed on a black prothallus; surface glossy, brownish. Medulla I−. Photobiont green, chlorococcoid. Ascomata apothecia, to 2 mm diam., rounded, semi-immersed to sessile, indistinctly marginate, black or brown-black. Exciple poorly developed, colourless. Hypothecium colourless. Hymenium to 190 μm tall, I+ blue. Hamathecium of conglutinate, branched-anastomosing paraphyses. Asci clavate, 8-spored, Porpidia -type (with an amyloid apical tube). Ascospores, large, halonate, simple, colourless at first becoming greenish or brown at maturity. Conidiomata pycnidia, immersed. Conidia cylindrical, 4–6 × 1– 1.5 μm.
Poeltidea, included in the family Porpidiaceae (Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005), is a monospecific genus occurring in alpine habitats in New Zealand, Australia. Kerguelen, South Georgia and Tierra del Fuego in southern South America (Hertel 1984b, 1987b, 1989b; Rambold 1989). It is characterised by a colourless hypothecium; asci of Porpidia -type; tall, I+ blue hymenium (to 190 μm); large, halonate, ellipsoidal ascospores that are colourless at first but which become greenish brown to dark-brown at maturity. The genus seems rather isolated within the family Porpidiaceae by its very large ascospores that become greenish brown during maturation.
