Amanita (ser. Amidella) PERS.

IDENTIFICATION KEY TO AMANITA PERS. SERIES AMIDELLA (E.-J.GILBERT) NEVILLE & POUMARAT

1. Pileus remaining convex for most of the development of the basidiome, sometimes with an umbo, diameter notably smaller than the length of the developed stipe, covered at least on the margin with heterogeneous scales from the inner layer of the universal veil, which become brown like the exposed context, stipe base bulbous, margin of the volva leaning towards the stipe, context discoloration moderate to intense. Rare occurrences, widely spaced in time (A. lepiotoides)............................................................................................................ 2

— Pileus becoming flat then depressed at the centre, diameter about the same as the stipe length, generally without scales, stipe slightly or not bulbous, margin of the volva free, pale context discoloration, rose then ochre. Occurrence generally annual........................................................................................................................ 3

2. Context discoloration intense, reddish then dark brown, stipe base distinctly bulbous, basidiospores mostly ellipsoid (Qm <1.65)...................................................................................... A. lepiotoides f. lepiotoides Barla

— Context discoloration moderate, rose then ochre, stipe base slightly bulbous, basidiospores mostly oblong and cylindrical (Qm> 1.65).................................................. A. lepiotoides f. subcylindrospora Neville & Poumarat

3. Occurrence in Autumn, on siliceous sandy soil............................................................ A. curtipes E.-J.Gilbert

— Occurrence from late winter (rarely in January) to spring, also early summer............................................... 4

4. Heavy habit, semi-hypogeous, typically with an earthy odour, associated with Cistus, basidiospores mostly ellipsoid to oblong (1.60 <Qm <1.80)......................................... A. ponderosa f. ponderosa Malençon & R.Heim

— Medium-sized (pileus diameter generally less than 10 cm)............................................................................ 5

5. On siliceous sandy soil, associated or not with Cistus, pines, etc., basidia with average length <55 µm........ 6

— On heavy, often naked soil generally of schists, mostly associated with Cistus, basidia with average length> 55 µm............................................................................................................................................ 7

6. Relatively small (pileus diameter usually around 5 to 6 cm and below 8 cm), taste of the context indistinct, basidiospores mostly oblong (1.8 <Qm <2.05)........................................................... A. curtipes E.-J.Gilbert

— Medium-sized (pileus diameter usually between 7 and 10 cm), taste can be slightly of hazelnut, then bitter, basidiospores mostly cylindrical (2.0 <Qm <2.4)........ A. pseudovalens var. pseudovalens comb. nov., stat. nov.

7. Odour and/or taste typically distinct, semi-hypogeous habit (A. ponderosa).................................................. 8

— Odour indistinct, aftertaste slightly bitter, epigeous habit, pileus margin occasionally with brown scales.................................................................................................................... A. pseudovalens var. tartessiana var. nov.

8. Basidiospores broadly oblong (Qm = 1.60 – 1.80), strictly thermophile......................................................................................................................................................... A. ponderosa f. ponderosa Malençon & R.Heim

— Basidiospores long-ellipsoid (Qm = 1.45 – 1.55), also in cooler areas...................................................................................................................................................... A. ponderosa f. valens (Gilbert) Neville & Poumarat

Only the European taxa within Amanita series Amidella are considered. Parts of the key are from the work of Neville & Poumarat (2004).