Sticta viviana

This lichen is flat, circular or irregular, and can be up to 5 cm (2 in) in diameter. It comprises lobes that are about 5–10 in (130–250 mm) long and 7–15 mm (0.3–0.6 in) wide. The upper surface of the lobes is dark brown and shiny, with a bumpy texture towards the tips. There are small, stick-like growths called isidia on the surface. The lower surface of this lichen is cream-colored and has a rugose to undulate texture. It is covered by a primary tomentum, which is dense and thick except towards the margin. The primary tomentum comprises soft, brown hairs 340–430 μm long and clustered in bundles of 12–20 branched hyphae. These hyphae have free, moniliform apices. There is also a secondary tomentum, thinly arachnoid and cream-colored to beige. It is formed by solitary hyphae 7–23 μm long and has free, septate apices.^[1]

This lichen does not have rhizines. Instead, it has sparse cyphellae on the center and margins of the thallus. The cyphellae are irregular to angular in outline and are cupuliform to urceolate with wide pores (0.3–0.7 mm diameter). They are sessile to suprasessile, which means that the basal membrane is at or above the level of the lower cortex, and the cyphellae margin is basally constricted. The margins of the cyphellae are erect to slightly involute and are cream-colored to golden brown. The basal membrane of the cyphellae, which covers the medulla, is white.^[1]

Sticta aymara has some similarities to S. viviana: characteristics such as small thalli size, the presence of isidia, and the absence of apothecia unite these two species. However, S. aymara has a dark brown, scrobiculate (covered with small, shallow pits) to faveolate (with small, depressed, and pit-like structures) upper surface with cream-coloured maculae (small, flat patches or spots on the surface).^[2]

Sticta viviana is an epiphytic lichen species that grows on the branches and twigs of shrubs and treelets in the páramo habitat. It is usually found in areas that are somewhat exposed to light. The paramo is a high-altitude ecosystem found in the northern Andes, which includes the mountainous regions of Venezuela, Colombia, Ecuador, Peru, and Bolivia. The habitat preference of Sticta viviana is likely influenced by the unique environmental conditions in the páramo.^[1]