Short-spored Subulicystidium (Trechisporales, Basidiomycota): high morphological diversity and only partly clear species boundaries Ordynets, Alexander Scherf, David Pansegrau, Felix Denecke, Jonathan Lysenko, Ludmila Larsson, Karl-Henrik Langer, Ewald MycoKeys 2018 2018-06-27 35 41 99 Ordynets & K. H. Larss. Ordynets & K. H. Larss. 2018 Basidiomycetes Hydnodontaceae Subulicystidium treatment-meta Fungi Subulicystidium rarocrystallinum Trechisporales 0 41 Basidiomycota species rarocrystallinum sp. nov.  Diagnosis. Differs from all other  Subulicystidiumspecies by cystidia which bear few spaced and irregularly located crystals and have a thick cell wall.   Type.   COLOMBIA. Cundinamarcha: 23rd kilometre of a highway from Medellin(direction SE) to Tenjo, alt  2600 m, 6.0605, -75.4095, on dead twig, 4 Jun 1978, L.Ryvarden(LR 15483 inO:F 918488).  Etymology.  rarocrystallinum(Lat.), having few spaced crystals on cystidium.  Description.   Basidiomataannual, effused, resupinate, fragile, porulose, thin, adnate. Hymenophore smooth, finely velutinous due to numerous protruding cystidia, whitish. Margin thinning out, adnate.  systemmonomitic. All septa with clamps. Subiculum thin, compact, with richly branched hyphae 3-3.5 µmwide, thin-walled to slightly thick-walled, hyaline and smooth. Subhymenium thin, compact, with richly branched hyphae 3-3.5 µmwide, thin-walled, smooth.  Cystidiasubulate, 45-65(-80) x3.7-5 µmincluding encrustation, projecting up to 50 µm, with especially thick-walled, occasionally slightly swollen (up to 5.5 µm), basal part, with outer hyaline crystalline sheath covering the whole cystidium except the tapering, thin-walled apex. Crystal protrusions on cystidium are moderately large, rectangular to rounded, rather sparse and allocated rather irregularly and mostly in the medial part.  Basidiasuburniform, 11-15 x4.5-5.5 µm, thin-walled, with 4 sterigmata and a basal clamp, without encrustation. Basidiosporescylindric, adaxial side slightly concave, L=(7.5-)8.0-10.5(-10.8) µm, W=(2.8)2.9-3.7(-3.8) µm, Q=(2.2-)2.5-3.2(-3.7), N=72/1, with minute apiculus, smooth, thin-walled, hyaline, negative in Melzer'sreagent.  Remarks on species. The few spaced far from each other crystals on cystidium and thick cell wall of cystidium are peculiar. Furthermore, in the single collection studied, cystidia were relatively infrequent and subhymenium was more compact than in other species. Species can be distinguished from  Subulicystidium brachysporumalso by larger cylindric basidiospores. 1978-06-04 L. Ryvarden COLOMBIA Tenjo 2600 6.0605 Cundinamarcha 7 -75.4095 Medellin 1 holotype