Image of Russula risigallina (Batsch) Sacc. 1915

Description:

Slo.: marelina golobica - Habitat: found in alpine valley, mixed wood edge with shrubs; dominant Picea abies, Fagus sylvatica, Corylus avellana, Rosa sp., Fraxinus ornus, etc.; about 5 m off the dirt forest road in steep, west inclined terrain; in shade and relatively humid place close to a mountain stream; calcareous ground; partly protected from direct rain by tree and shrubs' canopies, average precipitations ~ 3.000 mm/year, average temperature 6-8 deg C, elevation 680 m (2.200 feet), alpine phytogeographical region. - Substratum: forest soil. - Comments: Growing in a group of three pilei; pilei diameter 5(8) cm, stipe 4-5.5 cm high and about 1.2-1.5 cm in diameter; smell indistinctive, almost none; taste mild, only after a long time very mildly bitter/burning; flesh very brittle; SP yellow-ochre, oac856, abundant; pilei cuticle peeling easy. - Determination is not certain. According to Ref.:(1) the find is too robust There is also some ambiguity in literature regarding similar Rusullas with yellow hut. Among others, this observation can be also Russula acetolens, Rauschert. Both R. risigallina and R. acetolens are sometimes referred under common name R. lutea (Ref.: (2)). Both are supposed to be somewhat smaller in average than this observation. Although measured spore dimensions fit very well to R. risigallina, type of spore surface do hardly. Warts eventually appear too coarse (?) (Refs.:(2) and (3)). Both mentioned alternatives should have distinctly sweet and vinegary smell respectively, but our observation had no distinct smell. Also, Refs.:(4) and (5) disagree with these statements. If I follow Ref.:(5) this observation fits the best to the name Russula risigallina var. acetolens. No really better fit could be found. There is some ambiguity also regarding its taste. Trama and gills (a small piece of the edge of the pileus) certainly didn't have distinct, strong burning taste. However, it also was not completely 'mild' (as it should be for R. risigalina according most sources), but had a barely noticeable bitter/burning taste after a longer chewing being far of that what is usually meant by 'burning taste' with Russulas. - Spores coarsely warty. Dimensions: 8.0 (SD = 0.5) x 6.6 (SD = 0.4) , Q = 1.21 (SD = 0.05), n = 30. Olympus CH20, NEA 100x/1.25, magnification 1.000 x, oil; in water. AmScope MA500 digital camera. - Herbarium: Mycotheca and lichen herbarium (LJU-Li) of Slovenian Forestry Institute, Vena pot 2, Ljubljana, Index Herbariorum LJF - References: (1) Personal communication with Mr. Bojan Rot, www.gobenabovskem.com. (2) S. Buczacki, Collins Fungi Guide, Collins (2012), p 328. (3) R. Phillips, Mushrooms, Macmillan (2006), p 40. (4) M. Bon, Parey's Buch der Pilze, Kosmos (2005), p 60. (5) G.J. Krieglsteiner (Hrsg.), Die Grosspilze Bade-Wrttembergs, Band 2, Ulmer (2000), p 471.