TYPE SPECIES:
• A. sylvestris Cope, 1872 [nomen dubium] "woodland great wonder"
  
  MISASSIGNED SPECIES:
• A. milo Cope, 1874 [nomen dubium] == Thespesius occidentalis
• A. monoclonius Breihaupt, 1994 "one-sticked great wonder" == Styracosaurus sphenocerus
• A. mortuarius (Cope, 1874) [nomen dubium] (originally Polyonax) = Polyonax mortuarius
• A. prorsus (Marsh, 1890) (originally Triceratops) = Triceratops prorsus
• A. sphenocerus (Cope, 1889) [nomen dubium] (originally Styracosaurus) = Styracosaurus sphenocerus

Animalia
Vertebrata
Tetrapoda
Sauropsida
Archosauromorpha
Ornithodira
Dinosauria
Ornithischia
Ceratopsia
Coronosauria

The first ceratopsian genus to be named.