1	Tergite VII without P3a seta	2
–	Tergite VII with P3a seta	7
2	Sternite XI with 3+3 setae	3
–	Sternite XI with 2+2 setae	A. halae Szeptycki, 1997
3	Foretarsal seta δ4 in proximal position to base of c’	4
–	Foretarsal seta δ4 in distal position to base of c’	A. charrieri Shrubovych, Schneider & D‘Haese, 2012
4	Base of foretarsal sensillum a’ at level of seta a3 insertion	5
–	Base of a’ distal to seta a3 insertion, at level of seta δ2 insertion	A. occultus Szeptycki, 1979
5	Foretarsal sensillum a slender	6
–	Foretarsal sensillum a broadened basally	A. apuliacus Rusek & Stumpp, 1988
6	Foretarsal sensillum a’ short, reaching to base of sensillum t2	A. exiguus Condé, 1944
–	Foretarsal sensillum a’ long, reaching to base of sensillum b’	A. carpaticus Nosek, 1967
7	Sternite XI with 3+3 setae	8
–	Sternite XI with 2+2 setae	A. condei Nosek, 1983
8	Tergite VII without Pla seta	9
–	Tergite VII with Pla setae	12
9	Foretarsal sensillum a slender	10
–	Foretarsal sensillum a broad	A. ochsenhausenus Rusek, 1988
10	Tergite VIII with 16 posterior setae (P1 setae present)	11
–	Tergite VIII with 14 posterior setae (P1 setae absent)	A. alpinus Gisin, 1945
11	Foretarsal sensilla c and b equal in length, foretarsus long (110–125 µm)	A. gisini Condé, 1952
–	Foretarsal sensillum c clearly longer than b, foretarsus shorter (about 80 µm)	A. terricola Rusek, 1965
12	Foretarsal seta δ4 in distal position to base of c’	13
–	Foretarsal seta δ4 in proximal position to base of c’	15
13	Tergite VI with P3a setae	A. gigas Szeptycki, 1997
–	Tergite VI without P3a seta	14
14	Tergite I with Pla seta, foretarsal sensilla b and c long, surpassing base of seta γ3	A. berruezanus Aldaba, 1983
–	Tergite I without Pla seta, foretarsal sensilla b and c short, reaching to base of seta γ3	A. confinis maderensis Tuxen, 1982
15	Tergites II–VI with Pla setae	A. bulgaricus sp. nov.
–	Tergites II–VI without Pla seta	16
16	Foretarsal sensilla b and c equal in length	17
–	Foretarsal sensilla b and c differing in length	20
17	Foretarsal sensillum a long, surpassing base of seta γ3, foretarsus length about 80 µm	A. setosus Szeptycki, 1993
–	Foretarsal sensillum a short, not reaching base of seta γ3, foretarsus longer than 100 µm	18
18	Foretarsal sensillum c’ long, surpassing base of claw, sternite VI with simple spsm pores, foretarsus length about 115 µm	A. sinensis Wu &Yin, 2007
–	Foretarsal sensillum c’ short, not reaching base of claw, sternite VI with composed spsm pores	19
19	Sternite VII with seta Pc, foretarsus length about 100 µm	A. xerophilus Szeptycki, 1979
–	Sternite VII without seta Pc, foretarsus length about 120 µm	A. silvanus Szeptycki, 1991
20	Foretarsal sensillum b shorter than c	A. palissai Nosek, 1967
–	Foretarsal sensillum b longer than c	21
21	Foretarsal sensillum a long, reaching to base of seta γ3; sensillum d long, surpassing base of e; length of foretarsus about 100 µm	A. confinis (Berlese, 1908)
–	Foretarsal sensillum a short, not reaching to base of seta γ3; sensillum d short, not passing base of e; foretarsus length more than 110 µm	A. alni Szeptycki, 1991