Tapellaria albomarginata Lücking
Mycobank MB 517813
Thallus dispersed into rounded, partly confluent patches, 10–25 mm across and 10–15 µm thick, ecorticate, smooth, pale grey to white. Apothecia rounded to strongly irregular in outline, 0.3–0.5 mm diam. and 100–150 µm high; disc plane to slightly concave, black; margin thin, pale grey pruinose (in necrotic specimens pure black). Excipulum 20–30 µm broad, pale brown. Hypothecium 20–50 µm high, dark brown, K+ purplish. Apothecial base dark purplish brown. Epithecium distinct, 5–10 µm high, dark aeruginous brown. Hymenium 50–60 µm high, colourless. Asci 40–50 x 10–15 µm. Ascospores (6–)8 per ascus, ellipsoid, 3(–4)-septate, 14–20 x 3–6 µm, 3–5 times as long as broad, colourless. Campylidia sessile, 0.3–0.5 mm broad; lobe well-developed, hood-shaped, pale grey to white pruinose; socle not apparent. Conidia filiform with slightly clavate apex, usually enrolled, 3–7-septate, 20–40 x 2–2.5 µm, associated with scattered algal cells. Chemistry: no substances detected by TLC.
This species was considered conspecific with the paleotropical Tapellaria bilimbioides R. Sant. (Lücking, 2008). However, after further revision of the available material, it appears that the neotropical populations consistently have a slightly prominent and irregular, white-pruinose apothecial margin, whereas the few available paleotropical collections have apothecia with a non-pruinose, black, flush margin. Tapellaria albomarginata thus differs from T. bilimbioides in the same way as T. nana (Fée) R. Sant. differs from T. epiphylla (Müll. Arg.) R. Sant. or T. leonorae M. Cáceres & Lücking from T. nigrata (Müll. Arg.) R. Sant. (Lücking, 2008). The new species is externally most similar to T. leonorae, which has much larger, 7-septate ascospores.
The epithet refers to the white-pruinose apothecial margin.
Neotropical; apparently confined to coastal lowland areas.
Type:—COSTA RICA. Puntarenas: Isla del Caño Biological Reserve; 8°42’N, 83°52’W, sea level; lowland rainforest, foliicolous; Jul 1992, Lücking 92-3797 (F).
Additional specimens examined (paratypes):—None.
Sicut Tapellaria leonorae sed ascosporis minoribus 3-septatis differt.