Buellia De Not.
=HAFELLIA Kalb, H.Mayrhofer & Scheid., 1986
Type: Buellia disciformis (Fr.) Mudd, typ. cons. [=Lecidea parasema var. disciformis Fr.]
Type : Hafellia parastata (Nyl.) Kalb, H.Mayrhofer & Scheid. Lecidea parastata Nyl.]
Description : Flora (1985: 44). See also Orange, Coppins & Scheidegger in Purvis et al. (1992: 129–130) and Foucard et al. (2002: 11–25). Ascomata apothecia, cryptolecanorine (completely immersed in thallus and without an exciple), lecanorine, biatorine and lecideine. Exciple aethalea -type, vilis -type, dispersa -type and leptocline -type (Scheidegger 1993). Asci (4–)8(–many)-spored, clavate, 30–100 μm, Bacidia -type (Malcolm & Galloway 1997: 186). Ascospores brown, 1-septate, rarely 3-septate or submuriform, ellipsoidal, oblong or fusiform, straight or curved; wall is of uniform thickness (Buellia -type) consisting of four layers – the outermost layer, W1, is faintly pigmented, W2 is uncoloured and W3 is pigmented with greater intensity than W1. These three layers are very thin and are only easily seen after pretreatment of spores with K. The innermost layer, W4, is uncoloured and distinctly thicker than all the outer layers (Scheidegger 1993). Sometimes ascospores also with median (Physconia -type) or subapical (Callispora -type) thickenings. Outer spore wall smooth (psilate) or finely ornamented (striate, microrugulate, rugulate or microfoveate), seen under oil immersion. Conidiomata pycnidia immersed. Conidiophores Anaptychia -type. Conidia bacillar 10 × 0.7–1 μm.
Key
Buellia, included in the family Physciaceae nom. cons. (Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005), is a large, cosmopolitan genus of c. 400 species (Kirk et al. 2001) that is, with few exceptions, still very poorly known and collected outside of the Northern Hemisphere, where most recent systematic work has been done. European saxicolous species are discussed by Scheidegger (1993) who gives much useful information on the genus. Corticolous and lignicolous species from the Iberian Peninsula are treated by Giralt et al. (2000a), and Scandinavian taxa by Foucard et al. (2002). The taxonomy and phylogeny of species of Buellia with pluriseptate ascospores is discussed by Anders Nordin (Nordin 1996, 1997, 1999, 2000; Nordin et al. 1999; Nordin & Mattsson 2001). There is an extensive literature on Buellia, especially relating to Northern Hemisphere taxa and populations [see Imshaug (1951); Sheard (1964, 1992 – as Hafellia); Lamb (1968); Hafellner (1979); Bellemère & Letrouit-Galinou (1987); Scheidegger & Ruef (1988); Scheidegger (1993); Rambold et al. (1994); Nordin (1996, 1999, 2000); Kalb & Elix (1998); Moberg et al. (1999); Giralt & Llimona (2000); Giralt et al. (2000a); Grube & (Arup 2001); Trinkhaus et al. (2001); Foucard et al. (2002); Giralt & Nordin (2002), Bungartz (2004); Bungartz & Nash (2004a, 2004b); Bungartz et al. (2004a, 2004b); Grube et al. (2004d)]. In a recent account of corticolous and lignicolous tropical and subtropical species of Buellia s. lat., Marbach (2000) explored a more natural systematic concept based on anatomy, morphology, chemistry and ecology recording as independent segregate genera: Amandinea (q.v.), Baculifera Marbach & Kalb, Chrismofulvea Marbach, Ciposia Marbach, Cratiria Marbach, Endohyalina Marbach, Fluctua Marbach, Gassicurtia Fée, Hafellia Kalb, Marbach & Scheidegger, Hypoflavia Marbach, Sculptolumina Marbach, Stigmatochroma Marbach, and Tetramelas Norman (q.v.). Typification of Buellia is still unequivocally established. The question is discussed by Kalb & Elix (1998: 478–479), who select Buellia parasema De Not. as lectotype; by Moberg et al. (1999), who propose conserving Buellia with Buellia aethalea (Ach.) Th.Fr. as a neotype; and by Nordin (2000). Presently, Buellia De Not. nom. cons. is typified by Buellia disciformis (Fr.) Mudd, typ. cons. (Greuter et al. 2000: 178; see also Gams 2004). This view is adopted here.
Buellia is still much in need of collection and revision in New Zealand. Of the 18 taxa discussed in the Flora (Galloway 1985a) several are located elsewhere. B. litoralis is referable to Amandinea lecideina, B. nitrophila is referable to Rinodina otagensis, and B. punctata is referable to Amandinea punctata. Sixteen species are treated here.
