Basidiocarps (fruit bodies) are gelatinous and appear to be parasitic on ascomycetous fungi on wood.

Microscopically they are distinguished by producing septate basidia in chains which give rise to deciduous sterigmata.

Sirobasidium was introduced in 1892 by Swedish mycologist Gustaf Lagerheim and French mycologist Narcisse Patouillard for two fungi collected in Ecuador that possessed distinctive, catenulate, tremelloid basidia (septate basidia formed in chains).

[1][2] Fruit bodies are gelatinous and are variously pustular to foliose (with leaf-like or seaweed-like fronds).

The basidia are "tremelloid" (globose to ellipsoid or fusiform and vertically or diagonally septate) and catenulate (formed in chains), giving rise to fusiform sterigmata or epibasidia which detach from the basidia and then produce basidiospores.