Part of the Puccinia urticata aggregate, with aecia on Urtica dioica.
Urediniospores 26-28 x 23-26 µm, subglobose, the wall ca 2 µm thick with three equatorial pores. Telia chocolate brown to black, pulvinate, in lines, erumpent through the stomata of the host epidermis. Teliospores 50-65 x 18-21 µm, narrowly clavate and tapering gently towards the base, the apex 7-9 µm thick and rounded, the pedicels persistent, yellow-brown.
Description adapted in part from WIlson & Henderson (1966).