Biatoridium delitescens
≡Biatorella delitescens Arnold, Flora 59: 566 (1876).
≡Strangospora delitescens (Arnold) Coppins in B.J. Coppins et al. Lichenologist 24 (4): 368 (1992).
Description : Thallus of scattered granules or developing as an endophloeodal crust, pale or grey, sparse or absent. Apothecia 0.2–0.4(–0.5) mm diam., plane to convex, adpressed, ±dispersed, white to pale yellowish or pinkish brown, translucent when wet; true exciple poorly developed, not apparent, exhibiting a reduced textura globosa. Epithecium indistinct, colourless, not granular. Hymenium 50–70 μm tall, colourless. Hypothecium 35–65 μm thick, yellow-grey, clearly visible in K, densely interwoven I+ blue. Paraphyses 1–1.5 μm diam., very distinct in a gel matrix, scarcely branched, ±flexuose. Asci 50–55 × 20–22 μm, 100(–150)-spored, elongate-clavate; wall 2–2.5 μm thick, uniform. Ascospores 4–4.5(–5) μm.
S: Nelson (Clark Valley; Hackett River), Marlborough (Pelorus Bridge). On bark of Podocarpus totara, Salix sp., Schefflera digitata in lowland mixed podocarp or podocarp– Nothofagu s forest and alongside streams (Malcolm & Vězda 1997a).
?Cosmopolitan
Illustration : Malcolm & Galloway (1997: 186).
Biatoridium delitescens is a very inconspicuous species, distinguished by: the pale apothecia that are translucent when wet; the reduced thallus; and the polysporous asci.
