Lecidea verruca
Description : Lichenicolous, thallus small, round to irregular, 1–10 mm diam., on thalli of Aspicilia. Surface chalky white, cracked–areolate, 0.3 mm thick. Medulla I+ intense-violet. Apothecia round to irregular, 0.1–0.8(–1.2) mm diam., solitary or in small groups, in part sunk in thallus and then without margins, in other parts also somewhat raised with a thin margin, disc smooth, black, epruinose. Hymenium 50–70 μm tall, colourless, epithecium blue-green to olive-green, narrow. Hypothecium colourless. Paraphyses 2 μm thick, the apices swollen to 5 μm thick. Asci clavate, 35–42 × 8– 13 μm. Ascospores ellipsoidal to oblong–ellipsoidal, 8–12 × 4– 7 μm. Pycnidia immersed. Conidia bacillar, 8–16 × 1.5 μm.
Chemistry : TLC−, all reactions negative.
S: Canterbury (Tasman Valley near Ball Hut). On greywacke rock outcrop on ridge associating with Candelariella vitellina, Carbonea vitellinaria, Rhizocarpon geographicum. First collected in New Zealand by Dr Brian Fineran [2326 – CANU] (see Fineran & Dodge 1970), but still very poorly collected and understood here. Known also from Austria, the European Alps, Norway, Sweden and Iceland (Poelt 1961, 1980; Hertel 1970b, 1973; Nimis 1993; Santesson 1993; Türk et al. 1993). First recorded in the Southern Hemisphere from Argentina and Chile (Hertel 1989b: 225–226; 1997: 109), the specimens apparently not being lichenicolous.
Bipolar
Host (NZ): Aspicilia sp. Known elsewhere as an obligate parasite of Aspicilia grisea Arnold and A. simoënsis Räsänen (Santesson 1993).
Illustration : Hertel (1970b: 408, fig. 6).
* Lecidea verruca is a species very closely related to Lecidea tessellata Flörke [for distinction between these taxa see Hertel (1995: 174–177)] and is characterised by: the very small, chalky white thalli lichenicolous on thalli of species of Aspicilia; the I+ violet medulla; the round to irregular, flat, grey-black apothecia, solitary or in small groups; the colourless hypothecium; and ellipsoidal to oblong–ellipsoidal ascospores, 8–12 × 4–7 μm
