Upon hatching, the larvae burrow into the host and feed internally. Other tachinids lay their eggs on foliage, and the eggs hatch inside the host insect after it eats the foliage. Plate 5 . Still other tachinids, such as the one that parasitizes mole crickets, locates the mole cricket by its song and deposits live larvae on or near the mole cricket. This particular fly was imported from South America and has been released as a biological control agent at many locations in Florida.
Some nematodes are beneficial and attack harmful insects, especially soil-inhabiting species.
One example is the nematode that is parasitic on mole crickets. It was introduced from South America and has been released throughout Florida. Plate 6 . Microbial agents, or pathogens, are extremely important in naturally occurring biological control. Beneficial pathogens are very diverse and include fungi, viruses and bacteria.