Sawflies are wasps that lack stingers and look a lot like flies, but larvae are the better mimics.
Female Sawflies have a saw-like organ that helps them place their eggs inside twigs and stems for better protection from the elements and predators. Sawflies look like flies, but they are actually wasps. Fortunately, this type of wasps lacks a stinger. They may be brown, black, black and yellow, or black and red depending on the species.
The larvae of the Sawfly looks very much like a caterpillar. The body shape, colors, and patterns seen on sawfly larvae are also commonly see in butterfly and moth larvae. One way to distinguish between them is by counting the number of prolegs (the back legs). Sawflies have more than 6 sets, while caterpillars have fewer than that. Sawflies never get longer than 25 mm (1 inch), while caterpillars can span the palm of an adult's hand. Recognizing a sawfly larva is useful, especially if it is attacking trees and shrubs. Healthy plants can tolerate sawfly damage, but a large population of sawfly larvae can do serious harm to them.
Scientific Name: Tenthredo spp.
Fly or Mosquito
Colors: black; red
Descriptors: green caterpillar; wasp; harmless; flying
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