Melampsora hypericorum  

Spermogonia: not known.
Aecia: 0.5-0.8 (-1.5) mm diam., caeomoid (without a well-defined peridium), surrounded by flaps of host epidermal tissue when young, hypogenous, bright yellow to orange, shallowly pulvinate. Aeciospores formed in short chains, (18-) 24-28 x (10-) 14-20 (-23) µm, ellipsoidal or clavate, often polygonal due to compression, the outer spores usually larger and more rounded, with pale orange contents, the wall ca 2 µm thick, hyaline and multilayered, strongly verrucose, without pores.
Uredinia: not known.
Telia: ca 0.1 mm diam., hypogenous, rounded, at first reddish brown and darkening with age. Teliospores 28-40 x 10-17 µm, ± cylindrical, smooth, the wall ca 1 µm thick below and up to 3 µm thick at the ± rounded apex.