Herpothallon viridi-isidiatum is a species of crustose lichen in the family Arthoniaceae. Found in China, it was formally described as a new species in 2022 by Pengfei Chen and Lulu Zhang. The type was collected from the Baiyun Protection Station (Jingning County, Zhejiang) at an altitude of almost 1300m (4,300feet); here, the lichen was found growing on the bark of Cunninghamia lanceolata. The species epithet viridi-isidiatum refers to the greenish-coloured pseudisidia. Gyrophoric acid, lecanoric acid, and umbilicaric acid are all lichen products that have been identified in this lichen.