Caloplaca akbarica

Caloplaca akbarica, a species of lichen saxicolous (rock-dwelling), crustose lichen described in 2002. Found in Tajikistan, it has a rosette-shaped, thallus, and apothecia that are distinctly. It was formally described as a new species in 2002 by the lichenologists Imomnazar Kudratov and Oleksandr Khodosovtsev.

Description
Caloplaca akbarica has a rosette-shaped thallus, expanding to 2–3 cm in size. The of this lichen are yellow to orange, flattened, thin, and range in length from 1.5 to 3 mm, with a width of 0.5 to 1.0 mm and a thickness of about 0.2 mm. These lobes widen towards the tips and are closely placed or overlapping without apparent fissures, covered with a yellowish. The central part of the thallus comprises smaller lobes, measuring 0.3–1.0 by 0.2–0.3 mm, which are flat to slightly convex, orange, and may have small fissures or cracks. The cortex consists of several layers of cells.

Apothecia in C. akbarica are, measuring 0.5–1.0 mm in width, and numerous. They are sessile to constricted at the base and have a thick, bright yellow pruina. Initially, they develop as distinctly pruinose, contrasting with the orange thallus. The of the apothecia is concave to plane, covered with thick yellow pruina, and has a slightly  margin. The cortex is paraplectenchymatous, measuring 20–25 μm thick. The is well developed and consists of slightly elongated large cells. The is yellow, about 7–10 μm high, and the hymenium is hyaline, measuring 70–95 μm in height. The is also hyaline, standing 48–60 μm tall. Asci contain eight spores, with ascospores being ellipsoid and measuring 10.7–16.8 by 5.1–9.6 μm, having septa (internal partitions) of 1.4–2.8 μm.

Similar species
Caloplaca akbarica is distinguished from similar species by its flat, yellow-orange lobes with a distinct pruinose coating and the unique structure of its apothecia. It resembles Variospora aurantia in its flattened, pruinose lobes, yet differs in the shape of its ascospores. Compared to Massjukiella impolita, which has a flattened, yellowish pruinose thallus, C. akbarica differs in its narrower ascospores and wider septum. Unlike M. impolita, which tends to be coastal in western North America, C. akbarica is found in central Asia and differs in the more areolated central parts of the thallus.

Habitat and distribution
At the time of its original publication, Caloplaca akbarica was known only from its type locality in southern Tajikistan, specifically from the east slope of the ridge Gozimalik. It grows on exposed limestone at high elevations, around 1300 m.