Index Fungorum no. 220

Effectively published 24/02/2015 08:07:17  (ISSN 2049-2375)

Nomenclatural novelties : Christian Schwarz

Entoloma medianox C.F. Schwarz, in C.F. Schwarz, sp.nov.
Cap 3-15 cm broad, rounded-convex when young, margin often inrolled. Becoming broadly convex to plane, sometimes with a very low, round umbo. In age sometimes irregularly uplifted or wavy. Very young fruitbodies buried in duff pale whitish-beige to cream colored. Otherwise grayish-blue, sky-blue or powder blue, ranging through royal blue, but most typically dark grayish-blue to navy blue or midnight blue at maturity. At all ages can show a narrow and contrasting whitish margin, and often with a pale silvery bloom over the center of cap even in age. Occasionally specimens are irregularly pigmented with grayish-beige splotches and streaks. Surface smooth to strongly wrinkled-rivulose, viscid to dry. Gills whitish to creamy at first, often with a pale blue wash near the margin, becoming pinkish as the spores mature. Sometimes entirely washed bluish. Usually notched, sometimes narrowly adnate, fairly close, edges often irregular, gills sometimes wavy. Stipe 6-10 cm tall, 1.5-3 cm thick. Whitish, developing sky-blue to grayish-blue tones, sometimes yellowish near the base. Club-shaped or cylindrical, sometimes tapered at base. Usually fairly robust, surface often with silky-silvery sheen and vertically-marbled appearance. Surface nearly smooth and usually with thin, appressed chevrons of silvery or whitish tissue. Flesh whitish or pale bluish (especially near cap surface). Bruising reactions absent. Odor indistinct. Taste indistinct. KOH reactions indistinct or sometimes weakly orangey-brown on cap. Spore deposit cinnamon-pinkish to salmon. Microscopy: Spores 6.5–9 × 6–8.5 μm, slightly longer than wide, but angular, nearly isodiametric. Neither cheilo- nor pleuro- cystidia present. Pileipellis a loose, abundantly clamped cutis embedded in a viscid layer. Pigment intracellular, not making strong incrustations. Caulocystidia absent. Clamps present throughout.
    Holotype Holotype: UCSC-0340 .