E-Flora BC: Electronic Atlas of the Flora of British Columbia

Summary:
Features include minute, ochraceous brown disc-shaped fruitbodies seated on nearly round yellowish spots on living and dying leaves of Medicago, Trigonella, and Melilotus, and microscopic characters. The description is derived from Seaver(2). Schuepp treats this as a forma specialis of P. trifolii (Dennis(1)).

Pseudopeziza medicaginis is found throughout North America or wherever the hosts Medicago, Trigonella and Melilotus are grown. There are collections from BC, OR, and CO deposited at University of British Columbia.

Upper surface:
0.05-0.1cm across, expanded and subdiscoid [nearly disc-shaped], upper surface ochraceous brown

Stem:
seated on yellowish suborbicular [nearly round] spots, "opening with a laciniate aperture through the epidermis"

Microscopic:
spores 8-11 x 4-6 microns, ovoid, colorless, simple, biseriate; asci 8-spored, reaching a length of 75-80 microns and a width of 10 microns, subcylindric, narrowed in upper part, with stem; paraphyses filiform-clavate