Hellgrammite, found in rivers under rocks & used as Fish Bait. A.K.A. Grampus

Hellgrammites - New River Gorge National Park & Preserve (U.S. National Park Service)

Hellgrammite Missouri Department of Conservation

What the FUCK, is this? I found it under a rock while looking for crayfish in Pennsylvania USA : r/whatsthisbug

Cornelius' Corner: “Hello, Hellgrammites!” – Newlin Grist Mill

Hellgrammite Missouri Department of Conservation

Found a hellgrammite while fishing today. YIKES! : r/Fishing

Hellgrammite Missouri Department of Conservation

Hellgrammite, larva

The Hellgrammite: You Won't Believe this Strange Insect Exists!