Poison Ivy Sawfly – Arge humeralis


Poison Ivy Sawfly – Arge humeralis

color photo Poison Ivy Sawfly

Order Hymenoptera – Ants, Bees, Wasps and Sawflies
Symphyta – Sawflies, Horntails, and Wood Wasps
/ Family Argidae
This species is a leaf miner of the poison ivy plant, Rhus radicans.

Sawfly OvipositorSawfly Ovipositor (Dolerus nitens)

Sawflies get their name from the saw-like nature of their ovipositor. This female is using her saw to slit open blades of grass wherein she lays her eggs. It took me many attempts before I was able to capture this process. It is virtually impossible to tell what is going on while these creatures are laying eggs, it’s so quick, and the structures involved are so small.

color photo Poison Ivy Sawfly

This species is a leaf miner of the poison ivy plant, Rhus radicans. It is also a convincing mimic of braconid wasps. Unlike many hymenopterans, sawflies do not have stingers – their ovipositors developed into the eponymous sawlike devicecolor photo Poison Ivy Sawfly

There are 59 species of Argid sawflies in North America. They are most easily recognized as stout-bodied insects with three-segmented antennae; the third segment being very long. Many argid sawflies are black or dark colored, but a few have bright orange or red mimicking the coloration of the Braconid parasitic wasps.

Poison Ivy "leaves of 3"Poison ivy host plant

Reference: Bruce Marlin, Bugguide.net  Argid sawfly

Bees & Wasps Index | Bees & Wasps Main

Tree Encyclopedia / North American Insects & Spiders

Online since 2002