Allographa guainiae is a species of crustose lichen-forming fungus in the family Graphidaceae. It is a green-gray, bark-dwelling lichen with prominent, straight, slit-like fruiting bodies with distinctively grooved black lips. The species was described in 2023 and is known only from palm-dominated forest in GuainÃÂa, Colombia.
Allographa guainiae was described as a new species in 2023 by Robert Lücking, Norida Lucia MarÃÂn-Canchala, and Bibiana Moncada, based on material collected in Colombia (GuainÃÂa Department).
The body (thallus) is a crust growing on bark, up to 7 cm across and about 100âÂÂ150(âÂÂ200) üm thick. Its surface is coarsely uneven to irregularly warty (), green-gray, and dull; no visible border zone () is present, though a thin, irregular black line may appear where the thallus meets neighboring lichens. In cross-section, the thallus has a distinct, firm outer skin (, 15âÂÂ25 üm), a relatively thick (30âÂÂ70 üm), and a thick inner tissue (medulla, 50âÂÂ100 üm); crystals are present in both the algal layer and medulla, including clusters of calcium oxalate. The algal partner () is from the green algal genus Trentepohlia.
The fruiting bodies are slit-like structures () that are straight, unbranched, and prominently raised to sitting directly on the thallus surface (), with a thallus-derived rim along the sides (lateral ). They are typically 1âÂÂ3 (sometimes up to 5) mm long and 0.4âÂÂ0.7 mm wide, with the inner hidden from view. The lips () are black and distinctly grooved (striate), with whitish thallus remnants along the grooves; the outer wall () is completely blackened (). The spore-bearing layer (hymenium) is 130âÂÂ150 üm high and only very sparsely and finely permeated with oil droplets (). The asci are spindle-shaped (fusiform, 120âÂÂ130 à12âÂÂ15 üm), each containing eight ascospores. The ascospores are oblong, divided into 8âÂÂ10 cells (7âÂÂ9-septate), 25âÂÂ30 à6âÂÂ7 üm, and stain violet-blue with iodine. Stictic acid was reported as the secondary metabolite.
The species is known to occur only in its type locality in the municipality of Inirida, Guainia Department, Colombia, where it was found at elevation growing on bark in a palm-dominated forest with abundant chiqui-chiqui palm (Leopoldinia piassaba).