3. Clavariadelphus elongatus J. Khan, Sher & Khalid, Phytotaxa 365: 184, 2018 Figs 2d, 2e, 3c, 4c, 5c, 8a, 8b

Note.

The following description is taken from Sher et al. (2018), field notes of the Chinese material including macro-morphology, growth habit, distribution, host plants and our examination of the specimens.

Description.

Basidiomes up to 28 cm high, 0.5-1.0 cm diam. basally, enlarged upwards to 1.5 cm diam., subcylindrical to fusiform, simple or occasionally branched, laterally compressed in age; hymenium longitudinally rugose, plum colour (13C2-4) or light purple to greyish-purple (14C2-3) or dull-lilac (15D2-3); apex tapered, subacute to obtuse, initially smooth, rugulose in age, caramel-brown to sandy-brown or sienna (6C5-6); base terete, smooth, white; mycelial hyphae scant, white; flesh initially solid, then soft and spongy in age. Odour and taste not recorded.

Hymenium extending over the apex of the basidiomata, composed of basidia and leptocystidia. Basidia 75-95 × 6-10 μm, clavate, hyaline, thin-walled, 4-spored, sterigmata 7-10 μm in length. Basidiospores [40/2/2] (8.3-) 9.0-11.0 (-12.0) × (5.5-) 5.7-7.4 μm, Q = (1.43-) 1.44-2.04 (-2.31), Q m = 1.71 ± 0.16, narrowly ellipsoid to ellipsoid, ovate or amygdaliform, with a small apiculus, inamyloid, thin-walled, hyaline in KOH, smooth. Leptocystidia 70-75 × 3.5-4.5 μm, scattered amongst and scarcely projecting beyond the basidia, cylindrical to narrowly clavate, thin-walled, smooth, hyaline, non-pigmented, clamped, inflated apically at maturity, at times with apical or subapical branches. Mycelial hyphae 2-3 or 6-8 μm diam., interwoven or aggregated into rhizomorphic strands, branched, clamped; the hyphal walls echinulate with light microscopy, encrusted with massive triangular or irregular, flaky crystals up 1 μm high, which are insoluble in KOH.

Chemical reactions.

(dried basidiomes): KOH = positive, light yellow; FeCl3 = positive, green-yellow; NH4OH = positive, orange; ethanol, FeSO4, phenol and Melzer’s reagent = negative.

Known distribution and ecology.

NW and SW China (in this study), Pakistan (Sher et al. 2018). Solitary to scattered on the ground in coniferous woods ( Abies spp. and Picea spp.) or mixed with broad-leaved trees ( Quercus spp., Rhododendron spp. and Salix spp.) at elevations ranging from 3000-4350 m.

Materials examined.

China. Gansu Province: Zhouqu Prefecture, Shatan National Forest Park, Abies spp. woods, 16 August 2012, X.T Zhu 740 (HKAS 76589). Sichuan Province: Litang Prefecture, Gaowa, Kobresia-Bistorta meadows with extensive areas of dwarf Rhododendron and Salix scrub with Picea spp., 30°10.10'N, 100°35.12'E, alt. 4300-4350 m, 8 August 2006, Z.W. Ge 1221 (HKAS 50801); Yajiang Prefecture, meadows with shrub thickets and Picea spp. forests, 30°2.67'N, 101°18.48'E, alt. 3850-3870 m, 4 August 2006, Z.W. Ge 1162 (HKAS 50742). Yunnan Province: Yulong Prefecture, Lizui Village, mixed coniferous and broad-leaved forests of Picea spp. and Quercus spp., alt. 3000 m, 23 August 2007, Y. Zhang 36 (HKAS 52425); Shangri-La Prefecture, 27°29.00'N, 99°25.00'E, alt. 3600 m, 13 August 2008, T.Z. Wei 150 (HMAS 260746).

Comments.

Clavariadelphus elongatus was originally described from Pakistan (Sher et al. 2018). In this study, it was found in NW and SW China. This species is unique in its greyish-purple basidiomes with acute to subacute, non-enlarged apex, hyphae of the basal mycelium encrusted with massive, flaky crystals and basidiomes having a light yellow reaction to KOH. Clavariadelphus himalayensis, another Asian taxon, might be confused with C. elongatus since both have a tinge of grey-purple when young. However, C. himalayensis is distinct in having smaller basidiomes, pastel-red colouration at maturation, shorter basidiospores (8.2-9.4 × 5.0-5.5 μm), hyphae of the basal mycelium covered nipple-shaped protuberances without crystals and basidiomes having a brown-yellow reaction to KOH.

Phylogenetically, C. elongatus is related to C. pistillaris and the sequence of " C. occidentalis " from GenBank with weak support (Fig. 1).