Bunodophoron A.Massal.
Type : Bunodophoron australe (Laurer) A.Massal. [=Sphaerophorus australis Laurer]
Description : Thallus fruticose or palmate-foliose, heteromerous, of very variable morphology, branches ±dorsiventrally flattened, or in some cases ±terete (B. notatum, B. ramuliferum); commonly dimorphic, fertile branches larger than shorter, and often ±richly branched sterile branches. Cortex 45–130 μm thick, of thick-walled, fused hyphae, branching in various directions, Medulla lax, rarely hollow, I−. Photobiont green, Protococcus, confined to a distinct layer between cortex and medulla. Ascomata apothecia, terminal or (rarely) laminal on the lower side of fertile branches. Ascoma ontogeny angiocarpic; the excipulum disintegrates but, normally, encloses the mazedium until it is mature. Thalline receptacle lost early, or at least partially remaining throughout development. Mazedia subapical or ventral. Ascospores globose to subglobose, 4–21 μm diam., pale-grey or reddish brown, rarely almost hyaline, with varying amounts of dark ornamentation adhering to the wall after spores released from asci; greenish to greyish in K, reddish in HNO3; ornamentation dissolving in K. Conidiomata pycnidia, black to pale brownish, locate at tips and along lower side of terminal branchlets. Conidia hyaline, simple, bacillar to oblong, 3–8 × 1.5–2.5 μm. Chemistry : most species containing sphaerophorin; one or more β-orcinol depsidones occur in nearly all taxa, and usnic acid derivatives (isousnic acid being the most common) in a few taxa.
Key
Bunodophoron is included in the family Sphaerophoraceae (Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005). Recent studies in the family Sphaerophoraceae have led to reassessments of generic classification (Wedin 1993a, 1995a). The generic name Bunodophoron was reintroduced by Wedin (1993a: 231) for 20 species, mostly temperate Southern Hemisphere taxa formerly placed in Sphaerophorus Pers. In addition to the characters separating Bunodophoron from Sphaerophorus [Sphaerophorus has ascospore ornamentation formed of epiplasmic material deposited on the ascospore wall while still inside the asci], in Bunodophoron (and Leifidium) the ornamentation is from an electron-dense amorphous substance deposited and adhering to the ascospore walls when they are released into the mazedium. Also, the ascospores of Sphaerophorus are broadly ellipsoidal, the thalline exciple is globose; the ascospores are medium-sized, the medulla is often I+ violet, and thamnolic and/or squamatic acids are the major secondary compounds produced, it differs from Leifidium Wedin, in the ±flattened thallus, subapical to ventral exposed mazedium, and bacillar conidia. The genera Pleurocybe Müll.Arg. and Pseudosphaerophorus M.Satô were treated as synonyms.
Gargas et al. (1995) first suggested placing the family Sphaerophoraceae in the order Lecanorales, based on molecular studies using SSU rDNA data, a position supported by Wedin et al. (1998, 2000a), Wedin & Tibell (1997), Wedin & Döring (1999), Döring & Wedin (2000a, 2000b) and now widely accepted (Eriksson et al. 2004; Pennycook & Galloway 2004). The circumscription of Lecanorales is presently based mainly on the presence of the bitunicate lecanoralean ascus-type (Hafellner 1994c), a feature lacking and probably secondarily lost in the Sphaerophoraceae, where the asci must be regarded as having reverted to the pleisiomorphic, unitunicate and prototunicate stage (Wedin et al. 1998). On the basis of morphological, anatomical and chemical evidence Wedin et al. (1998) propose that the family Sphaerophoraceae belongs to one of the groups presently accommodated in the paraphyletic Cladoniineae, one of the suborders in the Lecanorales (Eriksson 1999).
Species of Bunodophoron are characteristic of Southern Hemisphere cool temperate rainforest and are conspicuous as epiphytes in these biomes in New Zealand and southern South America (especially Chile). Currently c. 30 species are recognised (Wedin 1995a, 2001a) of which 16 occur in New Zealand. Only a few species occur in the Northern Hemisphere, where they are found in highly oceanic habitats. Earlier accounts of New Zealand species (as Sphaerophorus) are those of Murray (1960a), Satô (1966, 1968c, 1969, 1975), Ohlsson (1974) Galloway (1985a) and Tibell (1987). The most recent accounts are those of Wedin (1995a, 2001a), whose taxonomy is followed here.
