An adult Tachinid Fly looks ugly, but grotesque diet of the larva feasts on a caterpillar's insides, saving the most important organs for until the end.
Tachinid Flies are covered in spiky black hairs. This species has a white face, red eyes, and a black body. A female Tachinid Fly will lay one or two fertilized eggs on, or near, a caterpillar. The caterpillar may even inadvertently eat the eggs as it chews through a leaf that the eggs were laid on. The fly maggot can also latch on to a passing caterpillar and promptly eat a hole into its body. The maggot then slowly feeds on the caterpillar's internal parts. Once it has mostly developed, it finally consumes the caterpillar's most necessary organs, killing the caterpillar. The culprit exits its dead host and moves to the ground where it will dig a hole to pupate in. Flying adults emerge from the ground.
The spiky, hairy adults drink nectar. Tachinid Fly larvae are efficient pest controllers for certain moth species. This particular species parasitizes some tiger moths and also some skipper species. Because of the parasitoid diet of their larvae, some species of Tachinid Fly have been deliberately imported from other continents to control destructive moth populations here in North America. However, some of these Tachinid Flies also eat caterpillars of much-loved native butterflies like the Monarch. Tachinid Flies are now a threat to those raising Monarchs, infecting at the caterpillar stage and killing in the chrysalis.
This particular species of Tachinid Fly can be found on flowers, in fields, parks or gardens during the summer and autumn. Look for big red eyes and spiky hairs on the abdomen to help differentiate them from House Flies.
Scientific Name: Juriniopsis adusta
Fly or Mosquito
Size (Adult; Length): 9mm to 15mm (0.35in to 0.59in)
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