Key to third-instar larvae of Heterogomphus
1 Tarsal claws with 2 setae ............................................................................................................................................. 2
- Tarsal claws with 4 setae ....................................................................................................... H. chevrolati Burmeister
2 Stridulatory area with 7 blunt, truncate ridges; antennomere 4 with 5 dorsal sensory spots............ H. pauson (Perty)
- Stridulatory area with 10 blunt, truncate ridges; antennomere 4 with 6 dorsal sensory spots........................................ ............................................................................................................................................... H . dilaticollis Burmeister