Tremella rubromaculata is a species of fungus in the family Tremellaceae. It produces reddish orange, lobed, gelatinous basidiocarps (fruit bodies) and is parasitic on other fungi on dead branches of broad-leaved trees. It was originally described from Guatemala.
Tremella rubromaculata was first published in 1964 by American mycologist Bernard Lowy based on a collection made in Guatemala.
Fruit bodies are gelatinous, bright reddish orange, up to 2.5 cm (1 in) across, and lobed. Microscopically, the basidia are tremelloid (ellipsoid, with oblique to vertical septa), 4-celled, 17 to 21 by 8 to 11 μm. The basidiospores are ellipsoid, smooth, 8 to 10.5 by 6 to 8 μm.
Tremella dysenterica, described from Brazil, is bi-coloured (yellow and reddish orange) and similarly lobed to subfrondose, but has smaller basidia and smaller spores (5.5 to 8.5 by 4 to 5.5 μm). Elsewhere, Tremella erythrina is similarly coloured, but only known from China.
Tremella rubromaculata is a parasite on lignicolous fungi, but its host species is unknown. It is found on dead, attached or fallen branches of broad-leaved trees.
The species was described from Guatemala and has also been reported from Brazil and Mexico.