Key to species of Typhloroncus (modified from Harvey & Muchmore, 2013)

1 Smaller, epigean species, palpal femur less than 1 mm in length................................................. 2

- Larger, troglobitic species, palpal femur more than 1 mm in length.............................................. 3

2 Eyes present........................................................ T. planodentatus (San Luis Potosí, Mexico)

- Eyes absent...................................................... T. coralensis (Saint John, U.S. Virgin Islands)

3 Ventrodistal telotarsal setae of legs strongly lanceolate........................................................ 4

- Ventrodistal telotarsal setae simple........................................................................ 5

4 Subterminal tarsal setae of legs strongly lanceolate............................... T. attenuatus (Tamaulipas, Mexico)

- Subterminal tarsal setae not modified.................................. T. guatemalensis sp. n. (Lanquín, Guatemala)

5 Palpal segments slender, femur of female 5.7 times longer than broad; chela (without pedicel) of female 4.5 times longer than broad....................................................................... T. diabolus (Veracruz, Mexico)

- Palpal segments very slender, femur of female greater than 7.0 times longer than broad; chela (without pedicel) of female greater than 5.5 times longer than broad.................................................................... 6

6 Palpal femur of female 7.3 times longer than broad; chela (without pedicel) of female 5.9 times longer than broad...................................................................................... T. troglobius (Puebla, Mexico) Palpal femur of female 7.6 times longer than broad; chela (without pedicel) of female 6.9 times longer than broad................................................................................ T. xilitlensis (San Luis Potosí, Mexico)