"[2] William Alphonso Murrill made it the type species of his newly created genus Nigroporus in 1905.

"[3] In the interim between Berkeley and Murrill's nomenclatural changes, the species was shuffled between several genera: Polystictus (Saccardo, 1888);[4] Microporus (Kuntze, 1898);[5] and Coriolus (Patouillard, 1900).

Pores on the cap underside any minute, numbering seven or eight per millimetre; the tubes are up to 3 mm (0.12 in) long.

Corner, "Some collections appear to be almost trimitic; others are dimitic and, yet, others are almost monomitic with elongate intercalary skeletal cells.

They are smooth and thin-walled, hyaline (translucent), with an allantoid (long with rounded ends) to broadly ellipsoid shape.

The basidia (spore-bearing cells) are thin walled and club shaped, measuring 6–10 by 3–4 μm.

Known from tropical regions and from Florida, this fungus has a larger cap that is up to 20 cm (8 in) wide, a hard dark brown to purplish black cap surface, a dark brown to blackish pore surface with pores arranged in a honeycomb, and ellipsoid spores measuring 4–5 by 3–3.5 μm.