Key to species of Petrobunus

1 Ocularium armed with a median tubercle (Sharma & Giribet, 2011:119, fig. 11b)............................ P. torosus

- Ocularium unarmed.................................................................................... 2

2 Free tergites with conspicuous tubercles (Sharma & Giribet, 2011:116, fig. 7a; 118, fig. 10a)................... P. spinifer

- Free tergites with granules or unarmed..................................................................... 3

3 Dorsal scutum or Opisthosomal sternite unarmed in male.......................................... P. hebei sp. nov.

- Dorsal scutum or Opisthosomal sternite armed tubercles (Fig. 1) or spines (Sharma & Giribet, 2011:112, fig. 4b) in male... 4

4 Scutal area V and free tergites I and II of male armed with paired enlarged lateral tubercles, opisthosomal sternite 7 of male with two large setose spines............................................................. P. chongqing sp. nov.

- Dorsal scutum unmared that of tubercles, opisthosomal sternite 7 of male with four large setose spines..... P. schwendingeri