Endoraecium auriculiforme McTaggart & R.G. Shivas
Uredinia on both phyllode surfaces, subepidermal, erumpent,
on bullate swellings up to 1 cm long, or pulverulent on phyllode
surface, linear to round, yellowish brown; paraphyses intrasoral, cylindrical, apex 6‒9-digitate, subhyaline to yellow,
35‒70 × 10‒14 μm, thickened at apex, pedicel up to 40 μm.
Urediniospores obovoid, oval to fusiform, apex acute, yellowish brown, 31‒46 × 16‒20 μm; wall 3‒5 μm thick at sides and 5‒9 μm thick at apex, foveolate, with 3‒4 equatorial germ pores; pedicel 3‒5 μm, or absent.
Telia formed from uredinia, erumpent, reddish brown
Teliospores cylindrical to fusiform, apex rounded, 2‒4-digitate, hyaline to subhyaline, 36‒54 × 13‒25 μm; wall 1.5‒2.5 μm thick at sides, 6‒8 μm thick at apex; pedicel persistent, up to 38 μm.
Basidia cylindrical, 3-septate, up to 35‒40 × 8‒12 μm.
Basidiospores globose, hyaline, 4‒6 μm, smooth-walled.
Endoraecium auriculiforme has foveolate urediniospores with an acute and thickened apex, and digitate paraphyses that resemble narrow teliospores. Endoraecium violae-faustiae and E. peggii also produce similar paraphyses. These three species all occur on hosts in the Juliflorae, with E. auriculiforme restricted to A. auriculiformis; E. violae-faustiae to A. aulacocarpa and A. crassicarpa, and E. peggii to A. holosericea.