Lecanora subimmergens

Lecanora subimmergens is a species of saxicolous (rock-dwelling) crustose lichen in the family Lecanoraceae.^[1] It is widely distributed, occurring in Asia, America, and Australasia.

It was described as new to science by the Finnish naturalist Edvard August Vainio in 1921. In his protologue, Vainio described the lichen as having a moderately thickened, smooth, areolate to cracked thallus composed of small, pale greyish-white, opaque areoles. He noted that the thallus had a yellowish reaction (lutescent) with potassium hydroxide solution (the K test), subsequently turning brownish. Vainio described the apothecia (fruiting bodies) as small, measuring 0.5–0.8 mm in diameter, initially immersed in the substrate but eventually slightly emergent, with a plane to occasionally slightly convex disc. The disc was reddish, smooth, slightly shiny, and had a thin, smooth margin, which was entire or rarely slightly flexuous. Internally, the hypothecium appeared pale, and the hymenium was approximately 70 μm thick, displaying a persistent blue reaction with iodine. Spores were described as colourless, simple, ellipsoid, measuring roughly 7 by 6 μm, with rounded ends. Paraphyses were closely coherent, thin, with reddish-brown epithecium. Vainio distinguished this species from related taxa by its smooth thallus and mostly immersed apothecia. The type specimen was collected from rock in Kōzuke Province, Japan.^[2]

Lecanora subimmergens is a saxicolous lichen with a nearly cosmopolitan distribution. It occurs in Asia, America, and Australasia.^[3]

• List of Lecanora species