Fissurina nicobarensis is a species of corticolous (bark-dwelling) script lichen in the family Graphidaceae.

[1] Found in the Nicobar Islands, it was formally described as a new species in 2012 by Bharati Sharma, Pradnya Khadilkar, and Urmila Makhija.

The lichen has a yellowish-brown thallus, which is warty and glossy and is delimited by a black hypothalloidal region.

The lirelline ascomata are branched, 1–10 mm long, semi-emergent, and have a creamish-coloured disc.

The ascospores are hyaline, somewhat muriform, and ellipsoid with a thin halo; they have dimensions of 10–15 by 6–7 μm.