Wight's Myriotrema Lichen

Leptotrema wightii

Leptotrema wightii (Taylor) Müller-Argau, 1882:499.

Endocarpon wightii Taylor, 1847:155 [type-collection: Madras, India, Wight (FH, lectotype; BM, G, isotypes); Figure 20c].

Thelotrema prevostianum Montagne, 1849:292 [type-collection: Antilles, Prévost s.n. (P, lectotype); Figure 5d].

Leptotrema prevostianum (Montagne) Montagne, 1856:364.

Thelotrema subconcretum Leighton, 1869:169 [type-collection: Central Province, Ceylon, Thwaites 89 (BM, lectotype; H, G, P, S, UPS, W, isotypes); Figure 20e].

Phaeotrema subconcretum (Leighton) Müller-Argau, 1887a:10.

Leptotrema subconcretum (Leighton) Müller-Argau, 1891:277.

Leptotrema flavicans Müller-Argau, 1888:114 [type-collection: Guarapi, Paraguay, Balansa 4170 (G, lectotype; BM, M, W, isotypes); Figure 20d].

Thallus pale greenish mineral gray, thick and epiphloeodal, bulging up and flaking away with age, surface smooth but grainy in appearance, the columnar cortex with or without red crystal masses (Figure 1d), forming colonies up to 10 cm broad; apothecia immersed, 0.2–0.3 mm in diameter, non-carbonized, without a columella; pore round, 0.08–0.11 mm in diameter, flush; hymenium about 100μ high; spores brown, 8/ascus, muriform with 4–6 transverse locules and 1–2 longitudinal locules, 9μ–11μ × 20μ–28μ, I– (Figure 20f).

CHEMISTRY.—No substances present except for the unidentified anthraquinone pigment.

HABITAT.—Tree trunks in dry scrub forest near sea level.

This pantropical species has been discussed in detail by Salisbury (1971). It seems to occur at low elevations in dry scrub forest and extends northward into temperate forests of North America and southward into Argentina.

SPECIMENS EXAMINED.—1 (35582, 35584), 3 (32918).