Common Horse Fly 
Common House Mosquito 
Common Lagoon Fly 
Common Ligyra Bee Fly 
Common Lovebug 
Common Picture-winged Fly 
Common red-legged robberfly 
Compost Fly 
Comptosia insignis 
Condylostylus caudatus 
Condylostylus comatus 
Condylostylus longicornis 
Condylostylus occidentalis 
Condylostylus patibulatus 
Condylostylus spp. 
Conophorus fenestratus 
Conops quadrifasciatus 
Copestylum fornax 
Cophinopoda chinensis 
Cordilura luteola 
Coremacera marginata 
Coyote brush bud gall midge 
Craneiobia tuba 
Creosote gall midge