Boletopsis nothofagi J.A. Cooper & P. Leonard

Cooper, Jerry A. & Leonard, Patrick, 2012, Boletopsis nothofagi sp. nov. associated with Nothofagus in the Southern Hemisphere, MycoKeys 3, pp. 13-22 : 17-18

Boletopsis nothofagi J.A. Cooper & P. Leonard sp. n.

Description.

Basidiomes fasiculate, occasionally solitary, centrally stipitate, tough and fibrous. Pileus more or less convex, 10-80 mm diameter × 5-20 mm high, becoming undulate and edge somewhat incurved when young, smooth to finely fibrillose, grey [1D1, 1E1] ( Kornerup and Wanscher 1989), weakly nigrescent when bruised and eventually becoming black. Stipe stuffed, clavate or cylindrical, 20-60 mm in length × 10-25 mm diameter, narrowing slightly at base and apex, smooth, dry, concolorous with pileus and darkening where bruised. Hymenial layer white 1-2 mm deep, bruising tan, pores angular, 2-3 per mm, drying pinkish tan, sometimes with lacerate edges. Pore layer extending slightly down the stipe and clearly delineated. Smell of dried material weakly of fenugreek, taste slightly acidic. Pileus immediately black in KOH, pigment leaching olivaceous black into white absorbent paper. Spore print not obtained.

Hyphal system monomitic. Pileus with a differentiated pileipellis consisting of a cutis, hyphae to 2 µm diameter, with brown plasmatic pigment, hyphal surface covered in small amorphous granular material becoming dark green in KOH and dispersing into medium. Subcutis with inflated gloeoplerous-like hyphae, thin-walled, to 6 µm diameter, clamped. Basidia pleurobasidial, cylindrical to clavate 5-10 × 20-30 µm, 4-spored, with basal clamp. Pores with fringe of slender clavate cystidia-like elements to 80 × 4 µm. Spores very pale tan, thin-walled, not dextrinoid or amyloid, non-cyanophilous, flat-topped tuberculate, with a narrowed waist. Spores dimensions are of a bounding rectangle encompassing maximum length and width of each spore. Length µ =5.3 µm, σ =0.5, width µ =4.1 µm, σ =0.5, Q µ =1.35, σ =0.2 (combined statistics of measurement of 4, 13, 26, 20 spores from three fruiting bodies of the three collections).

Distribution.

North and South Islands of New Zealand

Ecology.

ectomycorrhizal in southern beech ( Nothofagus ) forests and so far found only in association with Nothofagus fusca .

Etymology.

nothofagi for its ectomycorrhizal association with Nothofagus .

Conservation status.

Although there are no data on the stability of the population size or historical changes in distribution of this species, it is likely to be naturally uncommon according to the New Zealand Threat Classification System ( Townsend et al. 2008).

Holotype.

NEW ZEALAND, North Island, Rimutaka Forest Park (under Nothofagus fusca ), NZMG: 2671550E, 5982715N, 2nd May 201, D. Batchelor & P. Leonard, PDD96007 (PL3511)

Other specimens examined

. New Zealand, North Island, Rimutaka Forest Park (under Nothofagus fusca ), NZMG: 2671550E, 5982715N, 15th May 2009, T. Lebel, PDD95529 (JAC11078). West Bay, St Arnaud ( Nothofagus fusca ), South Island, NZMG: 1586280E, 5372097N, 11th May 2010, S. Kerr & P. Leonard, PDD96012.

Discussion.

Boletopsis nothofagi differs from described species in the more elongate spores with a narrow central waist, granular extra-cellular material becoming green in KOH and habitat in Nothofagus forests ( Niemala and Saarenoska 1989; Harrison 1975; Watling and Milne 2006).