Weird winged predator like creek creature (Dobsonfly)

Todays creek adventures were full of creatures,I was in about 3 feet of water sifting rocks out of a creek bottom when this creature showed up in my creature is stout bodied, winged,, with massive pinchers,it has a predator look,and can swim, crawl,or like what a dragonfly would look like inside Rob Zombies can go to flickr (Richrelics13) and see the up close cornutus female dobsonfly.