Flora of New Zealand Series

≡Calicium viridireagens Nádv., Preslia 18/19: 129 (1940).

Description : On lignum, usually associated with species of Chaenotheca, growing on thallus and occasionally also on apothecia of host, more rarely associating with sterile, crustose lichens. Apothecia 0.5–1.2 mm tall, often slender but sometimes with short stalks. Capitulum black, 0.16–0.22 mm diam., hemispherical to subspherical. Stalk black, dull or slightly shining, often slightly reddish in upper parts, 0.04–0.07 mm diam. Epithecium thin, brownish or olive-brown. Hymenium with numerous, colourless oil droplets. Hypothecium 40–80 μm thick, reddish to yellow-brown, with dark-red-pigmented granules to 6 μm diam., and with numerous small, colourless oil droplets. Exciple 50–60 μm wide, of 3–5 layers of parallel to irregularly interwoven hyphae, 10–14 μm thick with varying amounts of red pigment. All parts of apothecia with reddish pigment K+ aeruginose (persisting). Stalk swelling strongly in K. Asci 33–39 × 2.2–3.3 μm, cylindrical with thickened apex penetrated by a fine canal. Ascospores uniseriate in ascus, medium-brown, ellipsoidal, smooth, 1-septate, 6–7 × 2.2–2.7 μm, often with minute, yellowish red, oil droplets.

N: South Auckland (Pirongia) to Wellington (Tararua Ra.). S: Nelson (Abel Tasman National Park) to Southland (Pourakino Valley). On lignum, rarely on living bark in shaded, temperate rainforest, 150–1260 m. Commonly parasitic on Chaenotheca brunneola but also on other species of Chaenotheca. Known also from Europe, Scandinavia, Asia, North America, Australia and South America (Tibell 1999c: 49; McCarthy 2003c, 2006; Nimis & Martellos 2003; Tibell & Thor 2003; Hermansson & Pystina 2004; Titov et al. 2004).

Cosmopolitan

Exsiccati : Tibell (1982: No. 64).

Illustrations : Tibell (1987: 164, fig. 122; 1999c: 87).

Chaenothecopsis viridireagens is characterised by the presence of a reddish pigment that reacts K+ aeruginose in the hymenium, hypothecium, exciple, stalk and even in the spores; the smooth, 1-septate spores with a thin septum, and the strongly swollen and pale hyphae of the central part of the stalk.