Which family has tympana at the base of the front tibiae?

• A. Notonectidae (Backswimmers)
• B. Nepidae (Waterscorpions)
• C. Gryllotalpidae (Mole Crickets)
• D. Belostomatidae (Giant Water Bugs)

Answer: (C)

Hearing organs in insects come in a variety of placements, depending on their lifestyle. Mole crickets have tympana placed at the base of the front tibiae. This position suits their digging, subterranean life: the forelegs are in contact with the ground, so membranes at the leg bases can directly pick up vibrations and airborne sounds transmitted through the soil. Having tympana on both front legs also provides binaural input, helping them localize sound.

The other families listed are aquatic or semi-aquatic, and their auditory structures are located elsewhere—often on the abdomen or thorax—because their hearing needs and signal environments differ. This makes the base-of-front-tibia placement distinctive of mole crickets.