Notes:

Pileus: 2-4 cm in diam, fleshy-fragile, broadly conical with incurved margin when young to convex-conical to planar at maturity to uplifted-wavy in age, retaining a slight umbo throughout; 6F8 when young to 6E7 (disc) / 5B3 (margin) at maturity (5A2 at lightest), always some degree of darker at disk; texture smooth with faint, appressed, radial fibrils which are slightly darker than background; context thin (> 1.5 mm), unchanging when cut, 3A2 – 4A2; blackening/browning in KOH.

Lamellae: attached when young, receding/notched in age; 6B2 to 6e6; up to 8 mm broad, subdistant to crowded, average thickness; margin entire, encrusted with fine white crystalline structures (cheilocystidia?); lamellulae present in ~2 series.

Stipe: 3.5-7.5 cm in length, 2-5 mm thick, enlarged above and below (up to 9 mm); central; stuffed when young to hollow in age; upper 2 cm covered with cottony fibrils (PV remnants) which are whitish/cream colored above and spore covered below; cartilaginous, twisted fibrous; context 5E7 to 6F7, iridescent; context white above to 5D4 below.

Partial Veil: cottony fibrillose to cortinoid, cream colored with sparse orange coloring (6B6 – 6B5), flared upward, disappearing in age, sometimes leaving a hanging, fibrillose annulus covered in spores.

Spore Deposit: light medium brown

Odor/Taste: mild, grassy

Substrate: in dark, moist soil under cultivated Bambusa

Habitat: landscaped/cultivated area, ~3400m

Ecoregion: Central Andean Wet Puna (NT1003)

Collector(s): D. Newman

Collection #: DSN12.012