Micropsalliota cf. Roseipes Heinem., Bull. Jard. Bot. natn. Belg. 50(1-2): 65 (1980) (Figures 2H, 6, 10D)
Basidiomata stout (IG = 15–38). Pileus 6.0–10 mm in diameter, dirty white (1A1) to pink (11A5–11A6), expanding to plane, plane with aged, covered with dull red (11B4–11B5) to violet-red (11E7–11E8) squamules. Context less than 0.5 mm thick. Lamellae 0.5–0.1 mm broad, free, subdistant, with 2–3 series of lamellulae, white becoming light brown (6C6–6D6) as mature. Stipe 8.5–11.5 × 0.5–1.0 mm, cylindrical, dirty white (1A1) with some pinkish (11A5–11B5) tone, surface with white (1A1) fibrils. Annulus single, membranous, superior, white (1A1), easily fall off.
Basidiospores 5.5–7.0 × 3.0–4.0µm, av. = 6.2 × 3.6µm, Q = 1.60–1.90 (2.00), elongated, rarely ovoid in face view, amygdaliform in profile view, light brown, wall 0.2–0.3µm thick, apically thickened endosporium indistinct, without germ pore, inamyloid. Basidia 15.5–22.5 × 4.5–6.0µm, clavate, hyaline, 4-spored. Pleurocystidia absent. Cheilocystidia 19–29 (34) × 6.5–9.0 (9.5) µm, utriform with obtuse, subcapitate or capitate apex, 5.0–7.5µm in diameter. Pileipellis a cutis, hyphae (6.5) 8.0–18 (22) µm in diameter, constricted at the septa on some hyphae, with pink membranous pigment, or dark brown granular-incrusted in cellular vacuoles which can dissolve in 5% KOH (vacuolar pigment) in some hyphae.
Habit and habitat: Scattered on red soil in mixed forests.
Specimen examined: CHINA. Fujian Province, Wuyishan National Park, 20 June 2021, Jun-Qing Yan and Cheng-Feng Nie, HFJAU2494.
Notes: Chinese material closely matches the description of the type of M. roseipes, only differs in having narrower basidiospores, 3.0–4.0µm rather than 4.0–4.8µm (Heinemann, 1980). Micropsalliota roseipes is similar to M. cardinalis Heinem., M. rufosquarrosa and M. wuyishanensis, and groups together with M. rufosquarrosa in the phylogenetic tree; however, M. cardinalis has narrowly utriform cheilocystidia (Heinemann, 1989), M. rufosquarrosa has a white stipe and cheilocystidia covered by light brown deposition, and M. wuyishanensis has hyphoid and frequently forked cheilocystidia (this paper).
