Punctelia Krog
Type : Punctelia borreri (Sm.) Krog [=Lichen borreri Sm.]
Description : Thallus foliose, adnate to commonly loosely adnate, to 4–20 cm wide. Lobes subirregular to irregular, 2–15 mm wide; margins entire or incised, often sinuous and ±ascending, lacking cilia; apices rotund. Upper surface grey to grey-green (±atranorin and ±chloroatranorin), pseudocyphellate, emaculate with or without soredia and isidia; pseudocyphellae punctiform or suborbicular, scattered, not arranged in lines or in a ridged reticulum; upper cortex paraplechtenchymatous, with a non-pored epicortex. Cell walls containing isolichenan. Medulla white. Lower surface pale-tan or whitish brown or black, rhizinate, often with a naked, marginal zone. Rhizines simple, ±fasciculate, pale-buff to black. Ascomata apothecia, laminal, subpedicellate to pedicellate; disc entire, rarely perforate, concave or becoming undulating and ±flat and cracked, pale-brown to dark-brown. Ascospores subglobose to broadly ellipsoid, 8 per ascus, 10–27 × 6–18 μm. Conidiomata pycnidia, immersed, laminal or rarely marginal, punctiform, subglobose. Conidia unciform (5–7 × 1 μm) or filiform (7–12 × 0.8–1 μm).
Chemistry : With characteristic C+ orcinol depsides (lecanoric and gyrophoric acids).
Key
Punctelia is included in the family Parmeliaceae (Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005) and includes c. 30 species (Kirk et al. 2001; Egan & Aptroot 2004), with major areas of speciation being South America and Africa. It was segregated from Parmelia s. lat. by Krog (1982) and taxa are characterised by a grey, punctiform pseudocyphellate upper surface, and by unciform to filiform conidia. Useful information is found in Hale (1965a); Krog & Swinscow (1977); Galloway & Elix (1983, 1984); Elix & Johnston (1988a); Swinscow & Krog (1988); Elix (1994q); Adler & Ahti (1996); Kurokawa 1999a; Longán et al. (2000), Van Herk & Aptroot (2000), Kurokawa & Lai (2001), Aptroot (2003b), Crespo et al. (2004b) and Egan & Aptroot (2004). Six taxa are recognised in New Zealand.
