Subject: Fly on calico asters
Location: Kent County, Michigan USA
September 21, 2014 3:57 pm
What is the name of this cool fly I found enjoying calico asters in Michigan in late September? Thanks!
This is a Tachinid Fly in the family Tachinidae, but we are not certain of the species. Tachinid Flies are parasitic on other insects and arthropods. According to BugGuide: “Larval stages are parasitoids of other arthropods; hosts include members of 11 insect orders, centipedes, spiders, and scorpions. Some tachinids are very host-specific, others parasitize a wide variety of hosts. The most common hosts are caterpillars. Most tachinids deposit their eggs directly on the body of their host, and it is not uncommon to see caterpillars with several tachinid eggs on them. Upon hatching the larva usually burrows into its host and feeds internally. Full-grown larva leaves the host and pupates nearby. Some tachinids lay their eggs on foliage; the larvae are flattened and are called planidia; they remain on the foliage until they find a suitable host.”