Arthonia epiphyscia
Description : Lichenicolous, on both vegetative tissue and ascomata of host. Apothecia up to 0.2 mm diam., often in clusters, black, rounded, convex. Epithecium brown, K±, olivaceous. Hymenium to 35 μm tall, I+ vinous-red. Hypothecium colourless to dark reddish brown (K+ olivaceous). Paraphysoids 1.5–2.5 diam., apices expanded to 4–5 μm diam., dark-pigmented. Asci clavate, 35–45 × 14–16 μm. Ascospores 1-septate, oblong to soleiform, colourless, 10–14 × 3–5 μm.
N: Wellington S: Otago (Saddle Hill, Fairfield). On a range of lichens on trees, rocks and farmyard fences and railings: Hosts: Pseudocyphellaria cinnamomea, P. multifida, Xanthoria elegans, X. parietina (Kondratyuk & Galloway 1994, 1995a). Widespread in temperate to arctic areas: Europe, Scandinavia, Greenland, Canary Is, Morocco, South Africa, North America, southern South America (Argentina, Chile), Bouvetøya and S Orkney Is (Santesson 1960; Diederich 1986, 2003; Øvstedal & Hawksworth 1986; Alstrup & Hawksworth 1990; Galloway & Quilhot 1999; Øvstedal & Lewis Smith 2001; Triebel & Scholz 2001; Hafellner et al. 2002; Martínez et al. 2002; Nimis & Martellos 2003).
Bipolar
Hosts : Species of Caloplaca, Physcia adscendens, P. dubia, Phaeophyscia orbicularis, Pseudocyphellaria cinnamomea, P. multifida, Xanthoria elegans, X. parietina (Vouaux 1914a: 139; Santesson 1960; Hawksworth 1975; Alstrup & Hawksworth 1990; Kondratyuk & Galloway 1994).
Illustrations : Alstrup (1981: 121, fig. 2; 122, fig. 3); Boqueras (2000: 74, fig. 7G).
* Arthonia epiphyscia is characterised by: the lichenicolous habit (on members of the Lobariaceae, Physciaceae and Teloschistaceae where it produces ascomata on both vegetative thallus and ascomata of the host); the I+ red hymenium; dark-brown hypothecium, 4–5-μm-thick apical cells of paraphysoids; and colourless, 1-septate, soleiform ascospores, 10–14 × 3.5–5 μm. The species is discussed by Santesson (1960: 500–501).
