Lateral view of a Female Hexagenia limbata (Ephemeridae) (Hex) Mayfly Dun from the Namekagon River in Wisconsin

Hex Mayflies
Hexagenia limbata

The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.

Stream photos

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Hydropsyche (Spotted Sedge) Caddisfly Larva Hydropsyche (Spotted Sedge) Caddisfly Larva

Ventral view of a Hydropsyche (Hydropsychidae) (Spotted Sedge) Caddisfly Larva from the Yakima River in Washington

With a bit of help from the microscope, this specimen keys clearly and unsurprisingly to Hydropsyche.

9 Recently Added Photos

27" brown trout, my largest ever. It was the sub-dominant fish in its pool. After this, I hooked the bigger one, but I couldn't land it.

Troutnut is a project started in 2003 by salmonid ecologist Jason "Troutnut" Neuswanger to help anglers and fly tyers unabashedly embrace the entomological side of the sport. Learn more about Troutnut or support the project for an enhanced experience here.

Belostoma flumineum (Electric Light Bug) Giant Water Bug Adult Pictures

I'm glad I finally got one of these Belostoma water bugs under my good camera. I had been hoping to get one in my kick-net samples for a while with no luck, but I ended up finding this one drifting midstream just below the surface while I fished. I have frequently seen water scorpions do that, too, and I'm beginning to suspect that is a common situation travel for these large Hemiptera bugs, and perhaps the way trout are used to seeing them.

Ruler view of a Belostoma flumineum (Belostomatidae) (Electric Light Bug) Giant Water Bug Adult from the West Branch of Owego Creek in New York The smallest ruler marks are 1 mm.

Dorsal view of a Belostoma flumineum (Belostomatidae) (Electric Light Bug) Giant Water Bug Adult from the West Branch of Owego Creek in New York

Ventral view of a Belostoma flumineum (Belostomatidae) (Electric Light Bug) Giant Water Bug Adult from the West Branch of Owego Creek in New York

The bottom side of this bug was quite shiny, maybe iridescent, but in a way that's hard to capture in a photo. I tried to do it with this one but it doesn't show up well. It was very hard to photograph this thing's bottom side at all, because it was so quick and adept at flipping itself back over.

Belostoma flumineum (Belostomatidae) (Electric Light Bug) Giant Water Bug Adult from the West Branch of Owego Creek in New York

Belostoma flumineum (Belostomatidae) (Electric Light Bug) Giant Water Bug Adult from the West Branch of Owego Creek in New York

Giant water bug. This dangerous aquatic predator belongs to the species Belostoma flumineum, in a family known as the "toebiters"

Artistic view of a Belostoma flumineum (Belostomatidae) (Electric Light Bug) Giant Water Bug Adult from the West Branch of Owego Creek in New York

This is one of my favorite pictures. Belostoma and other Hemiptera bugs aren't fully aquatic, and when I stuck this one in my aquarium it quickly crawled out of the water and up to the highest point, a pair of tiny mushrooms growing on a soggy log.

Artistic view of a Belostoma flumineum (Belostomatidae) (Electric Light Bug) Giant Water Bug Adult from the West Branch of Owego Creek in New York

This giant water bug was collected from the West Branch of Owego Creek in New York on April 24th, 2007 and added to Troutnut.com by Troutnut on April 24th, 2007.

Discussions of this Adult

Check this bug out

8 replies

Posted by Troutnut on Apr 24, 2007

Last reply on Dec 10, 2009 by Jmd123

This is a new favorite specimen of mine.

I'll have a video up featuring this one showing its swimming posture, too.

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