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Megalospora sulphurata
Mey. & Flot.
Thallus crustose, continuous to irregularly cracked, greenish grey to greenish
yellow, delimited by a black hypothallus. Isidia and soredia usually absent (but
occasionally present). Apothecia lecideine, ca. 2 mm in diameter, the disc flat,
in larger apothecia becoming convex, red-brown to black, the margin
prominent, yellowish to chocolate brown to black. Spores colourless, 2-celled,
thick-walled, 2-8 per ascus. Photobiont: chlorococcoid. Spot-tests: upper cortex
K-, KC+ yellow, P-; medulla K-, C-, P-. - Most common in humid mid- to high
elevation forests above 700 m. Even found in disturbed sites and amidst man-
made vegetation types such as chenas, tea, pines and acacia plantations.
Common in home gardens in high elevation areas (Central Highlands and high elevation wet zone forests).
Megalospora tuberculosa
(Fée) Sipman
Thallus crustose, effuse, soft, filmy to powdery-granular, pale yellow to pale
green grey; prothallus absent or blue-black. Thalline granules aggregated, partly
corticate, breaking down into irregular clusters of yellow-green to grey, soon
confluent and
Lepraria
-like soralia which may cover most of the thallus.
Apothecia rare, lecideine, sessile, the disc brown to black, the margin paler or
concolorous with disc. Spores colourless, 5-11 transversely septate, thick-
walled. Photobiont: chlorococcoid. Spot-tests: upper cortex K-, KC+ yellow, P-;
medulla K-, C-, P-. - On mature trunks of trees in humid mid- to high elevation
forests above 700 m, also in disturbed sites and man-made vegetation types.
Common in home gardens in high elevation area (Central Highlands and high
elevation forests in the wet zone).
Menegazzia terebrata
(Hoffm.) A.Massal.
Thallus foliose, lobate, more or less radiate, often forming rosettes or rarely
spreading irregularly, rather closely attached throughout. Lobes more or less
inflated, contiguous, hollow inside. Upper surface grey, often with brownish
margins, shiny, smooth, with small rounded perforations. Lower surface
corticate, blackened, without rhizines. Soredia present on the upper surface,
arranged in lip-shaped to rounded, prominent soralia. Apothecia very rare,
lecanorine. Spores colourless, 1-celled. Photobiont: chlorococcoid. Spot-tests:
Cortex K+ yellow (atranorin), C-, KC-, P+ yellow-orange, UV-. Reported from
Sri Lanka but identification uncertain (this is a mainly temperate species).
Myelochroa aurulenta
(Tuck.) Elix & Hale
Thallus foliose, 4-10 cm wide, adnate; lobes 0.5-2 mm wide, sublinear. Upper
surface greenish grey, pustulate–sorediate. Medulla yellow beneath soralia and
cracks in upper cortex. Lower surface black, densely rhizinate; rhizines simple
or sparsely branched. Apothecia lecanorine. Spores colourless, 1-celled.
Photobiont: chlorococcoid. Spot-tests: cortex K+ yellow (atranorin). Medulla
more intensely yellow with spot tests (secalonic acid A, eumitrins F, D & I,
zeorin & leucotylic acid). - A pantemperate to pantropical, mainly corticolous
species occurring in all continents except Europe.
Myelochroa entotheiochroa
(Hue) Elix & Hale
Thallus foliose, 4–6 cm wide, loosely adnate to overlapping, lobes 3–5 mm
wide, entire with ciliate margins. Upper surface mineral grey to yellowish,
strongly wrinkled and ridged in older parts, flaking to expose the yellow
medulla. Lower surface black with simple to squarrosely branched rhizines.
Apothecia lecanorien. Spores colourless, 1-celled. Photobiont: chlorococcoid.
Spot-tests: cortex K+ yellow (atranorin). Medulla K-, C-, KC-, P-. - Both
corticolous and saxicolous in rather sheltered, humid situations, also reported
from Korea, Japan, Nepal, Thailand and India.
