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 Add this item to the list  811496 Original description
   
Remarks (public):The species is recognized by the relatively broad spores Qav. = 1.7, pointed cystidia, pseudorhiza, and a preference for growing on nitrophilous soil. Psathyrella orbitarum and P. orbicularis differ in having more elongate spores, reflected in the mean-values for the two species: Qav. = 1.8-2.1. Moreover, P. orbitarum lacks a pseudorhiza and P. orbicularis has less frequent clavate cells on gill edge near cap margin. The two species are molecularly well separated from P. sublatispora 
Description type:Original description 
Description:Etymology. The name refers to the relatively broad spores.
Cap 10-25 mm broad, convex, sometimes with umbo or wavy, dark reddish brown (Mu. 5YR 3/4) with darker umbo, striate almost to centre, pallescent on drying; veil as dispersed fibres halfway to centre. Gills medium spaced, L = 20-24, adnexed, brown, with white fimbriate edge. Stem 40-70 x 1.5-2 mm, with a 8-15 mm long pseudorhiza, pale brown, fibrillose lower part, pulverulent at apex. Smell and taste not distinctive.
Spores 9.5-11 x 5.5-7 µm, av. 10.1-10.7 x 6-6.4 µm, Qav. = 1.7, oblong, ellipsoid, rarely ovoid, with obtuse base and apex, in profile sometimes subamygdaliform, in water red (Mu. 2.5YR 4/8-5/8), with distinct germ pore. Basidia 4-spored, 18-24 x 9-10 µm. Basidia or other cells in hymenium sometimes partly brown intracellular pigmented, sometimes surrounded by pseudoparaphyses like coprinoid species. Pleurocystidia 40-50 x 10-16 µm, conical to lageniform, scattered, pale. Cheilocystidia of two types: A: 25-40 x 8-13 µm, similar to pleurocystidia, numerous or rather numerous, B: 10-15 µm wide, clavate, scattered to numerous, increasing in frequency towards cap margin. Scalp cap half-way from margin: pileipellis with subglobose to ellipsoid 10-40 µm wide cells, pale; pileitrama with strongly pigmented hyphae. Hymenophoral trama moderately pigmented. Clamps seen on stem hyphae.
Habitat and distribution: Solitary to gregarious, on the margin of an old potato field on sandy soil with Senecio vulgaris, Polygonum aviculare, Chenopodium album and Artemisia vulgaris, also among grass on a path through a grove. Found on two localities in Sweden.
 
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