This lichen is characterized by its small, closed, and densely branched , as well as that are smooth at their tips. These features distinguish it from the similar
Fissurina dumastii, which has larger lirellae and a different appearance.
Fissurina amazonica has a greyish-green
thallus with a smooth to uneven texture, which can reach up to in diameter; there is no
prothallus surrounding the thallus. Its partner is
Trenephlia, a genus of
green algae. The of
Fissurina amazonica are
ellipsoid to oval in shape, contain 3
septa, and measure 13–17 by 6–8
μm. They are
hyaline and have lens-shaped to angular . Only a few ascospores have been observed in the available material, so their full range of morphological variation is not yet known. No
secondary chemical
substances have been detected in
Fissurina amazonica, and both the
medulla and microscopic
sections showing negative reactions to standard
chemical tests. ==Habitat and distribution==