A Lichenological Legacy – Festschrift Thomas H

8. Phyllopsora cognata (Nyl.) Timdal comb. nova
Lecidea cognata Nyl., Annls Sci. nat., Bot., sér 4, 19: 347 (1863). – Psorella cognata (Nyl.)
Zahlbr., Catal. Lich. Univers. 4 (26): 402 (1926). – Type: CUBA, s. loc., Wright, Lich. Cub. 218
(BM, lectotype selected here; BM, UPS, isolectotypes) [atranorin (major)].
(Colour Plate 14B)
Description: Prothallus thin, white. Thallus effuse, crustose, not radiating at the
margin. Areolae small, up to 0.1 mm wide, discrete when young, soon adjoining
to form a more or less continuous crust, pale green (old herbarium material), dull,
epruinose, glabrous. Isidia and soredia lacking (but see below). Upper cortex
poorly defined, 5–10 μm thick, containing crystals dissolving in K. Medulla
containing crystals dissolving in K, K+ faintly yellow. Apothecia common, up to
1.5 mm diam., plane when young, becoming weakly to moderately convex,
yellowish brown, rounded to irregular, simple to conglomerate, with a thin, more
or less persistent, paler, glabrous margin. Excipulum pale brown to colourless,
containing crystals dissolving in K, K–. Hypothecium pale brown, not containing
crystals, K–. Epithecium colourless, K–. Ascospores acicular, simple, with up to 3
pseudosepta, 19–30 × ca. 1.5 μm (n = 20).
Chemistry: atranorin (major).
Notes: The species is known only from Wright’s collections in Cuba. No original
specimens were located in H-NYL, but No. 218 in Wright’s exsiccata is assumed
to be a part of the original material and a specimen in BM is here selected as the
lectotype. Wright’s exsiccata No. 217 (BM, UPS) may belong in the same species
but is sorediate; more material is needed to decide if the presence of punctiform
soralia is a part of the variation of P. cognata. See also P. pertexta for discussion.
BRAKO (1989) did not include the species in Phyllopsora because it was said to
possess different tissue types in the exciple and hypothecium; thinner, less
gelatinized paraphyses; and long, septate, filiform ascospores. It fits Phyllopsora
in the broader concept of the genus adopted here, however (see discussion on the
circumscription of Phyllopsora in TIMDAL 2008b).
Specimens examined: CUBA. Wright, Lich. Cub. 218 (BM, lectotype; BM, UPS isolectotypes).
9. Phyllopsora confusa Swinscow & Krog
The Lichenologist 13: 229 (1981) – Type: KENYA (see SWINSCOW & KROG 1981). – Descriptions:
TIMDAL & KROG (2001), ELIX (2009).
(Colour Plate 14C)
Chemistry: no lichen substances (by TLC).
Notes: The species is characterized by the thin, white or sometimes partly reddish
brown prothallus, the small to medium sized, narrow (up to 0.3 mm wide),
ascending, more or less imbricate squamules which easily break off diaspores
terminally (lacinules), the lack of lichen substances, the pale apothecia with pale
exciple and hypothecium, and the narrowly ellipsoid to shortly bacilliform
ascospores. Phyllopsora chlorophaea differs mainly in having a thicker, always
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