Fascinating Lichens of Sri Lanka

Megalospora
Teloschistales Megalosporaceae
30
Megalospora is a genus which is mainly restricted to the tropical regions of the
world, but also extends into temperate regions, especially in Australasia. Species
are found on bark, and rarely on wood, leaves or rock, mostly in rather humid
situations. This genus is conspicuous and can be easily spotted by anyone who
closely looking for lichens.
Two species are widespread in Sri Lanka, but are often misidentified. Both
species were already recorded in early lichen collections from many areas of
Sri Lanka. These species are widely distributed in the wet zone, sub-montane
and montane regions, both in natural and man-made vegetation types of Sri
Lanka. The thallus could be green to grey or brown on both species. The thallus
tends to take on shades of green in wet conditions. The thallus turns to shades
of grey in open, exposed or disturbed conditions at high elevations. The thallus
is often surrounded by a black hypothallus. Both species have very similar thallus
characters, so careful observation is needed.
Megalosporaceae
Apothecia Sessile, disc brown to black, flat, margin pale brown to black;
Asci: 1-8-spored; Spores: ellipsoid, transversely septate or muriform, hyaline
(transparent, colourless), and with a thick wall.
Chemistry Thallus K+ yellow, P+ red, UV+ yellow.
Megalospora sulphurata
Description The thallus is crustose, corticate, continuous, wide, smooth, and
grey to whitish grey in colour. Species present in shaded habitats can have a
greenish-grey thallus. A black hypothallus is present. Soredia are not observed.
Apothecia are sessile with a brownish reddish black disc, and flat, margin
chocolate brown to black.
Status More common than Megalospora tuberculosa. Often seen on the mature
trunks of trees in shaded interiors or open forests.
VC
Cr
Megalosporaceae
Habitat Mostly found in humid mid elevation to high elevation forests above
700 m. Even found in disturbed sites and amidst man-made vegetation types
such as chenas, tea plantations, pines and acacia plantations. Common in home
gardens in high elevation areas.
Locations Central highlands and high elevation wet zone forests.
116 Fascinating Lichens of Sri Lanka
Fascinating Lichens of Sri Lanka 117