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Cantharidae = Link 1
These are the "soldier beetles," which are primarily predaceous. However, some species are phytophagous. Adults of many species of Cantharis and Podabrus feed extensively on aphids, and the larvae of C. rustica Fall. are known to feed on grasshopper eggs and larvae of Lepidoptera and Coleoptera. Larvae of Chauliognathus marginalis often enter the burrows of Heliothis obsoleta F. in corn to destroy them, and C. pennsylvanicus Deg. destroys many adult Diabrotica late in the season when they are inactive. The latter was noted by C. V. Riley to be predaceous in the egg masses of locusts (cited by Clausen 1940). Although adults and larvae are mainly predaceous, they also may feed on a wide array of plant materials, including plants seeds, roots, etc.
Eggs are laid in masses in the soil or beneath various objects and hatch in about one week. The newly hatched larvae of some species are embryonic in form, having their appendages weakly developed. Such larvae have been called "prolarvae." The intestine is filled with yolk, which serves as food until the first molt. Pupation occurs in cells in soil.
There are 1-2 generations per year, and they overwinter in the advanced larval stage in sheltered spots. Adult beetles are found mainly during early summer. Cantharis rufa var. lituratus Fall, is an omnivorous feeder, but at times it derives the bulk of its food from syrphid larvae, Platycheirus albumanus F., which enters the soil for hibernation and pupation (Payne 1916). Larvae feed readily on seeds of cereal crops but vegetables are only incidentally attacked.