1 (2) Apophyses posteriorly on prodorsum expressed as 3–5 pairs of discrete or fused tubercles overhanging dorsosejugal scissure. Femur I with 3 tubercles positioned antiaxially and dorsally in proximal third of leg. Known from California...................................................................................................... A. aokii sp. nov.
- Apophyses posteriorly on prodorsum expressed as 1 pair of discrete tubercles, or as flattened ridge, overhanging dorsosejugal scissure. Femur I without tubercles on proximal third of leg.................................................... 2
2 (1) In both sexes, apophysis posteriorly on prodorsum expressed as pair of flattened ridges. Circular cluster of tubercles present lateral of lamellar seta. Males with oblong porose area posteromedially positioned between lyrifissures ips, 27 wide x 19 and bearing unmodified seta h 1. Known from North Carolina, Virginia, Alabama, Ontario......................... A. amnica
- In both sexes, apophysis posteriorly on prodorsum expressed as pair of tubercles. Cluster of tubercles lateral of lamellar seta absent. Males with either long porose area posteromedially or oblong porose area with setae h 1, p 1 modified.............. 3
3 (2) In both sexes, notogastral setae thick, weakly barbed, tapered. Bothridial setae clavate to fusiform. Males with long, narrow porose area, ca. 176 long and 7–10 wide, extending between setae h 3 –h 3, not bearing either of setae h 1 and p 1; setae h 1 and p 1 not modified. Known from Virginia, Alabama, Ontario, Québec, Nova Scotia, New Brunswick, Newfoundland................................................................................................... A. longilamellata
- In both sexes, notogastral setae thin, acuminate. Bothridial setae clavate or capitate. Males with setae h 1 and p 1 modified.... 4
4 (3) In both sexes, bothridial setae fusiform. Notogastral setae long, thin acuminate, almost flagellate. Males with setae p 1 and h 1 spatulate, with small barbs bilaterally, positioned almost in transverse alignment on porose area 49–53 wide. Known from
Alberta, British Columbia.................................................................. A. flaheyi sp. nov. - In both sexes, bothridial setae with capitate head. Notogastral setae short, thin, acuminate, except p 1 and h 1 of male. Males with posteromedial cavity, about 20 wide, positioned between lyrifissures ips, bearing strongly modified setae h 1 and p 1 internally in cavity. Known from California............................................................. A. schusteri sp. nov.