Agaricales » ‎Agaricaceae » Lepiota

Lepiota condylospora

Lepiota condylospora Sysouphanthong, K.D. Hyde & Vellinga

MycoBank number: MB 833709; Faces of fungi number: FoF 0707.

Pileus 5–16 mm diam, first hemispherical or conical, expanding to campanulate, umbonate or plano-convex, with a wide umbo and inflexed margin; with a orangish brown to brown (7C6, 6E8) central calotte (sometimes reduced to the umbo), and irregularly shaped brown (6E8) squamules scattered toward the margin on a white fibrillose background; margin with only a few squamules, fringed, exceeding lamellae when mature. Lamellae free, crowded, ventricose, 3 mm deep, white to yellowish white (4A2), with floccose eroded white edge. Stipe 30–50 × 1–1.5 mm, cylindrical to slightly tapering to apex, with white to orange-white (6A2) background, covered by white fibrils, staining light brown (7D5) when touched, sometimes with brown (6E8) squamules at base zone. Annulus cufflike, white, cottony or fibrillose, with or without brown (6E8) squamules at the edge, attached at the upper part of the stipe. Context white to orange-white (6A2) in the pileus, 1–1.5 mm wide; orange-white (6A2) at the top of the stipe, light brown (7D5) towards its base. Smell strong and acrid. Taste mild and sweet. Spore print white. Basidiospores [75,3,3] 5.0–7.5 (–8.5) × 3.5–5.5 μm, avl × avw = 6.2 × 4.3 μm, Q = 1.3–2.0, Qav = 1.6, in sideview ellipsoidal to triangular, with an acute apex, in front-view star-like, with two lateral knobs, dextrinoid, more or less congophilous, cyanophilous, not metachromatic. Basidia 15–18 × 6.0–8.0 μm, 4-spored, rarely 2-spored, clavate, wider in the middle and narrower towards base and apex, with internal drops and granules visible in Congo Red, with basal clamp-connection. Lamella edge sterile. Cheilocystidia 17–29 × 10–15 μm, irregularly clavate, narrowly clavate or narrowly pyriform, sphaeropedunculate. Pleurocystidia none seen. Pileipellis a hymeniderm composed of more or less clavate elements, 16–66 × 9–23 μm, pale yellow, with hyaline or granular hyphae in the innermost layer, 3–13 μm wide, with clamp-connections. Stipitipellis (squamules) a hymeniderm similar to pileipellis. Clamp-connections present in all tissues.

Habitat and distribution: growing in small to large groups, rarely solitary, on humus rich soil with dead leaves and deciduous wood in mixed forests dominated by Castanopsis spp. and Lithocarpus spp; only known from Chiang Mai province, northern Thailand.

 Additional materials examined:   THAILAND. Chiang Mai: Mae Taeng Dist., near Forest of Pong Dueat Village, N 16° 06’ 16.1”, E 99° 43’ 07,9”, alt, 780–805 m, 30 July 2008, P. Sysouphanthong, MFLU 09–0173; Chiang Mai, Mae Rim Dist., Mae Sa Valley, 12 July 2008, P. Sysouphanthong, MFLU 09–0136.

Notes: Lepiota condylospora is a slender species with a campanulate, hemispherical to convex-umbonate pileus. It is recognized by the brownish orange to brown squamules on the pileus surface, the triangular basidiospores with two lateral knobs, and a hymenidermal pileipellis composed of clavate elements. So far, two species of Lepiota with laterally knobbed basidiospores and a hymenidermal pileipellis have been described: L. fraterna E. Horak, originally described from Papua New Guinea (Horak 1981), and L. cristata var. macrospora (Zhu L. Yang) Liang & Yang from southwest China (Liang & Yang 2011). Lepiota condylospora differs from L. fraterna in the bigger spores and cheilocystidia as well as the non-striate pileus margin (Horak 1981). Unfortunately, no ITS sequences of L. fraterna are available yet. Lepiota condylospora closely resembles L. cristata var. macrospora in most morphological characteristics, but the basidiomata are smaller, and the ITS sequences are notably different, suggesting that L. cristata var. macrospora nests within the

Fig. 2 Basidiomata of L. condylospora (a, MFLU090136; b, MFLU0900032). Photographs: P. Sysouphanthong.