Colonies effuse, irregular, black, hairy to velutinous thin or dense. Mycelium immersed, composed of subhyaline to brown, branched, septate hyphae 3-5um wide, densely aggregated around the base of the conidiophores in the form of a small, dark stroma up to 30um wide. Conidiophores occurring singly but usually in tufts of up to 3, erect, straight or flexuous, cylindrical. 100-230gm long, 5-7um wide, thick-walled, smooth, brown, up to 7-septate, with the cells 15-25um long. terminating in a single phialide.

Phialide robust, brown, 25-50um long and composed of a cylindrical venter, 5-6µm wide and a terminal slightly inflated light brown collarette, 18-20 X 10-13um; after the production of a succession of conidia the phialide may proliferate percurrently to produce successively a series of up to 6 phialides, the conidiophore then reaching a total length of up to 1000um

Phialoconidia clavate, bluntly rounded at the apex truncate at the base, 18-27 x 9-11µm, brown to dark brown, thick-walled, 3-septate, each septum obscured by a darker band in the outer wall. often persisting in chains of 10 to 15 conidia or gliding on each other into a mass at the tip or along the side of the phialide.