Flora of New Zealand Series

Description : Lichenicolous, causing discoloured, grey to black patches or gall-like outgrowths on host tissue. Perithecia, ±immersed, black, 140–190 μm diam.; ostiole (6–)12–18 μm diam.; peridium brown to dark-brown, in upper part 24–50(–55) μm thick, in lower part 12–20(–36) μm thick. Hamathecium of pseudoparaphyses, branched, to 2.5 μm thick. Asci cylindrical to elongate-clavate, thick-walled, 80–105 × 12–16(–18) μm, KI−, 4(–8)-spored. Ascospores ±ellipsoidal, brown at maturity, end cell often paler, (2–)3-septate, with torus, constricted at septum and with a pore through each septum, smooth, (18–)20–25(–27.5) × (5–)7.5–10(–12) μm.

S: Westland (Lake Brunner), Canterbury (Hanmer State Forest), Otago (Weller's Rock near Otakou), Southland (Bluff, Doubtful Sound). On lichens from inland and coastal rocks. This fungus has a wide host spectrum including some 21 different crustose or foliose lichens on various substrata. It is known from Great Britain, Europe, Scandinavia, Asia, Greenland, North America, Jamaica, The Canary Is, Cape Verde Is, Africa, Australia and New Zealand (Hawksworth 1980a, 1983b; Triebel 1989; Alstrup & Hawksworth 1990; Mies & Lumbsch 1990; Triebel et al. 1991; Kondratyuk & Galloway 1994; Hafellner 1996b; Ihlen 1998; Triebel & Scholz 2001; Alstrup 2004).

Cosmopolitan

Hosts : Degelia gayana (Matzer & Hafellner 1990: 70), Pseudocyphellaria dissimilis, P. pickeringii, Xanthoria elegans (Kondratyuk & Galloway 1994: 28 – as "Pyrendidium actinellum" [sic]), Rinodina peloleuca (Matzer et al. 1998: 184). [In the Northern Hemisphere it is common on species of Peltigera as well as on Aspicilia calcarea, Baeomyces rufus, Caloplaca teicholyta, Diploschistes caesioplumbeus, Fulgensia fulgida, Lecanora jamesii, Leptogium teretiusculum, Massalongia carnosa, Phaeophyscia hispidula, Physcia caesia, Solorina crocea, S. saccata and Toninia squalida (Hawksworth 1980, 1983b; Cole & Hawksworth 2001).]

Illustrations : Hawskworth (1980a: 369, fig. 1 – as * Dacampiosphaeria rivana); Eriksson (1981: 141, fig. 192).

* Pyrenidium actinellum is characterised by: the lichenicolous habit; well-developed pseudoparaphyses; thick-walled, 4-spored asci; brown, 3-septate ascospores, (18–)20–25(–27.5) × (5–)7.5–10(–12) μm; and a varied host range including Degelia, Pseudocyphellaria, Rinodina peloleuca and Xanthoria elegans.