Aspicilia aquatica
Description : Thallus bluish grey, rather velvety, areolate, areolae 0.5–1 mm diam., separated by narrow to gaping cracks, and delimited at margins by a thin, fimbriate prothallus. Apothecia frequent, innate, solitary to 2–3 per areola, 2–0.5 mm diam., with a ±prominent, thin margin, concolorous with thallus or darker. Epithecium olive green or brownish, 20–25 μm thick. Hymenium 110–180(–200) μm tall. Paraphyses 2–3 μm thick, apices submoniliform, slightly swollen. Asci 85–135 × 25–35 μm, 8-spored. Ascospores broadly ellipsoidal, 22–27(–35) × 14–18 μm.
Chemistry : TLC−, all reactions negative.
S: Otago (Canyon Creek). On streamside rocks, partly submerged, associating with Verrucaria aquatilis and Rhizocarpon geminatum. Known also from northern Europe, Scandinavia, North America and the Antarctic (Magnusson 1939; Nimis 1993; Santesson 1993; Esslinger & Egan 1995; Øvstedal & Lewis Smith 2001; Nimis & Martellos 2003; Santesson et al. 2004).
Bipolar
Illustration : Foucard (1990: pl. 25).
Aspicilia aquatica is characterised by: the saxicolous (periodically inundated streamside rocks) habit; the blue-grey, rather velvety, areolate thallus; 8-spored asci; and broadly ellipsoidal ascospores, 22–27(–35) × 14–18 μm.
