The
thallus of
Relicina colombiana is small and foliose, ranging from wide. It is tightly attached to its , with individual either separate or occasionally overlapping. The lobes are linear-elongate, 0.2–1.0 mm wide, and dichotomously branched with , sublinear . cilia are conspicuous, forming a dense marginal fringe and are often forked and black. The upper surface is pale yellow-green, smooth to , and , without
isidia. The
medulla is white, and the lower surface is black with sparse
rhizines.
Apothecia are not observed, but
pycnidia are common and immersed with a (dot-like)
ostiole.
Conidia are , measuring approximately 3 by 1
μm. The
secondary chemistry of the species includes a range of
lichen products, such as
usnic acid (major),
norstictic acid (major),
stictic acid (submajor),
constictic acid (minor),
salazinic acid (trace),
cryptostictic acid (trace),
peristictic acid (trace), and
connorstictic acid (trace).
Similar species In terms of overall
morphology and chemistry,
Relicina colombiana is similar to
Relicina subabstrusa. However, it can be distinguished by its smaller thallus (1–3.5 cm wide) with narrower lobes (0.2–1.0 mm wide) and the presence of dense marginal lobules. Additionally, it contains medullary stictic and constictic acids in substantial amounts, whereas
R. subabstrusa contains only norstictic and connorstictic acids in the medulla. While
R. subabstrusa is widely distributed in northeastern Australia, Southeast Asia, South America, and the Indian Ocean, and grows on the trunks and branches of trees across various habitats,
R. colombiana is limited to
quartzitic rock in the paramo zone of the Eastern Cordillera of Colombia. ==Habitat and distribution==