1 Male mandibles with bifurcate or trifurcate apex....................................................................... 2

— Male mandibles with simple apex, not bifurcate or trifurcate. São Paulo, Piquete (Pico dos Marins).................................................................................................................. A. campoi sp. nov.

2(1). Male mandibles longer than head in lateral view. Female head slightly convex on disc; pronotum entirely punctate, punctures moderate to coarse. Clean specimens without blue iridescence 3

— Male mandibles shorter than head in lateral view. Female head concave on disc; pronotum smooth, finely punctate. Clean specimens with blue iridescence............................................ 6

3(2). Male head near anterior margin at middle with a conspicuous process. Mandibles with apex trilobed. Female unknown. Minas Gerais, Passa Quatro (Serra Fina).................................................................................................................. A. trifurcatus (Grossi and Racca-Filho)

— Male head simple, without any process. Mandibles with apex bilobed...................................... 4

4(3). Male mandibles robust, with apical bifurcation wide and with at most 3 internal teeth. Female canthi projected laterally; internally with a strong and hollowed dorsal concavity; pronotal disc moderately densely punctate; puncture size moderate. Elytra with lines of moderately sized punctures. Rio de Janeiro, Itatiaia (Vale das Prateleiras).............. A. rotundatus (Boileau)

— Male mandibles slender with apical bifurcation narrow. Female without the combination of characters listed above............................................................................................................. 5

5(4). Male pronotum projecting forward and with a small pit at middle. Female canthi not projected, in the same plane as eye surface, concavity when present situated more laterally; pronotal disc densely punctate; puncture size large. Elytra with lines of large to coarse punctures. Minas Gerais, Itamonte (Serra Negra)..................................... A. dulceae (Bomans and Arnaud)

— Male pronotum not projecting forward, widely concave anteriorly. Female canthi less concave than A. dulceae; pronotal disc moderately punctate; punctures moderate. Elytra with lines of fine to moderate punctures. Rio de Janeiro, Itatiaia (Morro do Couto)....................................................................................................................... A. godinhorum (Bomans and Arnaud)

6(2). Male mandibles with a strong upturned basal tooth; pronotum in both sexes reddish, with anterior margin slightly concave. Elytra black; elytral punctures fine. Rio de Janeiro, Itatiaia (Pico das Agulhas Negras)........................................................................... A. ruficollis (Lüderwaldt)

— Male unknown. Female pronotum and elytra totally red. Anterior pronotal margin simply convex. Elytral punctures moderate to large. Minas Gerais, Passa Quatro (Serra Fina)...................... ........................................................................................................................ A. koikei Grossi