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Myelochroa irrugans
(Nyl.) Elix & Hale
Thallus foliose, 4-10 cm wide, loosely adnate to imbricate, lobes 2-4 mm wide
with dentate to crenulate margins with short cilia in lobe axils. Upper surface
greenish mineral grey to yellowish grey, older parts becoming foveolate,
developing c. 1 mm wide lobules. Medulla pale yellow to white. Lower surface
brown to black, with simple to squarrosely branched rhizines. Apothecia
lecanorine. Spores colourless, 1-celled. Photobiont: chlorococcoid. Spot-tests:
cortex K+ yellow (atranorin). Medulla K–, C–, KC–, P-. - Mostly on twigs in
humid, montane, mossy forests; an Asian species, also reported from Japan,
Korea, Saghalien, China, Taiwan, Nepal, Thailand and India.
Myelochroa subaurulenta
(Nyl.) Elix & Hale
Thallus foliose, closely adnate, to 7 cm wide, lobes closely imbricate, to 4 mm
wide, more or less truncate at apices and sparsely ciliate mainly in the axils;
upper surface grey to yellowish grey, smooth. Medulla yellow to pale orange–
yellow. Lower surface black with dense, simple to squarrose margins; rhizines
up to margins. Apothecia lecanorine. Spores colourless, 1-celled. Photobiont:
chlorococcoid. Spot-tests: Cortex K+ yellow (atranorin). Medulla K+, C+, KC+,
P+ orange red. - Mostly corticoluos in upland areas; an Asian species,
previously reported also from India, Thailand and Japan.
Myriotrema
spp.
Thallus crustose, endophloeodal to epiphloeodal, usually a shade of olive or
grey, with greenish to yellowish or whitish tones. True cortex and protocortex
present. Prothallus thin to indistinct, pale to dark brown. Apothecia more or less
rounded, rarely elongate, solitary to fused, rarely forming stroma-like structures.
Proper exciple non-amyloid to amyloid basally, hyaline to pale yellowish, rarely
orange internally, yellowish to brownish marginally, apically often darkened or
covered by granules. Hymenium non-amyloid, usually not inspersed,
conglutinated; paraphyses often with thickened apices, septate, often branched;
lateral paraphyses and true columella absent, but fused ascomata often with
columella-like structures. Epihymenium colourless, with or without granules.
Asci (1-)8-spored, clavate; wall and apex non-amyloid. Ascospores 1–2-seriate,
transversely septate to submuriform or muriform, colourless to brown. Conidia fusiform or bacilliform. Photobiont:
Trentepohlia
. - Several species are known from Sri Lanka, e.g.
M. microporum
(Matale) and
M. polytretum
(Ratnapura).
Normandina pulchella
(Borrer) Nyl.
Thallus squamulose, heteromerous, in irregular patches up to a dm or more in
diam. but usually much smaller. Squamules plane to concave, rounded and
shell-like, with sharply raised margins, undivided or with distinct marginal
lobes, 1-4 mm wide, 30-70 µm thick, sometimes becoming leprose, scattered or
partly becoming contiguous forming dense colonies. Upper surface pale grey-
green to glaucous green, with greenish farinose soredia along the margin.
Apothecia: unknown. Photobiont: chlorococcoid. Spot-tests: all negative. - A
widespread, temperate to pantropical species.
Ocellularia
s.l. spp. (incl.
Chapsa
)
Thallus crustose, endo- to epiphloeodal, usually a shade of olive or grey, with greenish to yellowish or whitish tones.
True cortex or a protocortex present in epiphloeodal thalli. Prothallus thin or indistinct, pale to rather dark brown.
Apothecia more or less rounded, rarely irregular or elongate, solitary to strongly fused, rarely forming stroma-like
structures. Proper exciple brown to blackish brown or pale yellowish, rarely colourless, apically often darkened or
covered by granules. Hymenium non-amyloid, inspersed with oil droplets or small crystals, or clear, conglutinated;
