How to identify it?
Cap
Cap 6-14 cm across, convex, becoming broadly convex or flat; yellowish brown to tawny or cinnamon brown; surface moist or fairly slimy; turns to brown when damaged or rubbed.
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Flesh
Flesh thick, soft, pale yellow. Taste mild or slightly acidic.
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Scientific Classification
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Phylum
Club fungi Class
Mushroom-forming fungi Order
Boletes and allies Family
Suillaceae Genus
Slippery jacks Species
Fat jack