Key to Aphilodon species

1. Cephalic plate longer than wide, without a distinct transverse suture; coxosternite of second maxillae more or less quadrangular, only slightly shorter in the middle part................................................................. 2

- Cephalic plate wider than long, with a distinct transverse suture (Fig. 17B); coxosternite of second maxillae distinctly shorter in middle part (Fig. 7A)........................................................................ A. micronyx

2. Antenna less than 2.7 times as long as cephalic plate; metasternite of ultimate leg-bearing segment wider than long....... 3

- Antenna more than 3.0 times as long as cephalic plate (Fig. 15B); metasternite of ultimate leg-bearing segment longer than wide (Fig. 14B)............................................................................. A. spegazzinii

3. Forcipular tarsungulum shorter than trochanteroprefemur+femur; metasternite of ultimate leg-bearing segment length/width ratio> 0.6........................................................................................... 4

- Forcipular tarsungulum longer than trochanteroprefemur+femur (Figs 19B, 20C); metasternite of ultimate leg-bearing segment length/width ratio <0.5 (Fig. 19C, 20G)...................................................... A. caboclos n. sp.

4. Pectinate lamella of mandible with straight denticles; ultimate presternite visible in males and females................. 5

- Pectinate lamella of mandible with curved denticles (Figs 25 A–B); ultimate presternite not visible in males and females (Figs 25E, 26E)............…....................................................................... A. pereirai n. sp.

5. Forcipule with distal denticle of trochanteroprefemur and denticle of femur separated at their bases; body in adults less than 25 mm long; up to 59 pairs of legs; up to 15 coxal pores on each coxopleuron in adults................................ 6

- Forcipule with distal denticle of trochanteroprefemur and denticle of femur with coalescent bases (Figs 27B, 28C); body in adults more than 30 mm long; 69 or more pairs of legs; more than 20 coxal pores on each coxopleuron in adults (Fig. 28E)........................................................................................ A. silvestrii n. sp.

6. Forcipule with at least distal denticle of trochanteroprefemur and denticle of femur relatively large.................... 7

- Forcipule with distal denticle of trochanteroprefemur, denticle of femur and denticle of tibia almost absent (Fig. 21A).......................................................................................... A. indespectus n. sp.

7. 45 or more pairs of legs; forcipular pretergite not covered by cephalic plate....................................... 8

- Up to 39 pairs of legs; forcipular pretergite totally covered by cephalic plate (Fig. 24B)................ A. meganae n. sp.

8. Cephalic plate length/width ratio <1.20 (Figs 40 A–D); antenna distinctly tapering to tip; less than 10 coxal pores on each coxopleuron in adults.................................................................................. 9

- Cephalic plate length/width ratio ca. 1.25; antenna not distinctly tapering to tip; more than 15 coxal pores on each coxopleuron in adults (Silvestri, 1909: Fig. X).............................................................. A. intermedius

9. Up to 45 pairs of legs; denticle of trochanteroprefemur and denticle of femur relatively large, denticle of tibia almost absent; approximately 5 coxal pores on each coxopleuron in adults (Silvestri, 1909: Fig. XI)....................... A. modestus

- Around 53–59 pairs of legs; denticle of trochanteroprefemur, denticle of femur and denticle of tibia relatively large; 7–10 coxal pores on each coxopleuron in adults (Fig. 18D).................................................... A. angustatus