Fissurina indica
Fissurina indica is a species of corticolous script lichen in the family Graphidaceae. Described in 2012 from specimens collected in India's Western Ghats, this lichen forms pale green to brownish crusts on tree bark in humid evergreen forests. It produces small, slit-like fruiting structures that lack the black walls typical of many related species, and its ascospores are divided into multiple brick-like compartments. The species has since been found in Assam, suggesting a wider distribution across India's moist hill forests than originally known.
Taxonomy
Fissurina indica is a script lichen in the family Graphidaceae. It was described in 2012 by Bharati Sharma, Pradnya Khadilkar and Urmila Makhija on the basis of a specimen gathered in the moist evergreen forest of Wayanad. The holotype came from bark in the Wynad Wildlife Sanctuary, and the specific epithet denotes its Indian origin.The species was one of nine Fissurina taxa newly introduced in the same treatment; subsequent floristic surveys have confirmed its presence farther north-east in Assam, indicating a wider distribution within the Indian subcontinent than the type locality alone suggests. The original authors placed F. indica among others in the genus that have dumastii-type, a that helps distinguish it from relatives such as F. cingalina and F. dumastii.
Description
The thallus forms a continuous, glossy crust of pale green to greenish-brown that becomes cracked and with age. A narrow black often outlines the colony. Slender lirellae—each 0.2–0.4 mm long—are scattered across the surface; they share the thallus colour, taper to sharp points and sit flush with the before the surrounding tissue splits slightly and raises them. Their walls remain pale and never develop the thick black carbon layer seen in many graphid lichens.Internally the colourless hymenium produces hyaline, spores. The ascospores measure 32–42 × 12–20 μm and are enveloped by a faint gelatinous that is best seen in water mounts. No lichen secondary metabolites have been detected by thin-layer chromatography or standard spot tests, a trait that also helps separate the species from chemically productive members of the genus.