There are over 400 species of Predaceous Diving Beetles in North America and the adults range from 1-40 mm in length. This is the larva of one of the large ones (Dytiscus spp.). This individual is a young one (35 mm long), but will grow to about 70 mm - roughly the size of your little finger. Those very large mandibles may look intimidating, but ... OK, there's no but here - these guys are every bit as nasty as they look!! They are also known as water tigers though IMO this doesn't do them justice as they are way more voracious than tigers. Food items include other aquatic invertebrates, tadpoles, and small fish. Prey items are captured with the mandibles which have a hollow tube running through them - body fluids of the prey are sucked up through the tubes. This is another aquarium shot. 5D II, 100 mm macro, 1/100, f/16, ISO 100, MT-24 EX macro twin flash (diffused), tripod, cable release. I removed tiny bits of debris from the water and cloned some specular highlights from the substrate. NR on the background. All comments are welcome and appreciated.
This is pretty amazing Steve! I love the tilt of the larva's head for a view of the top of the head, and your square crop works perfectly with the upturned tail. I really gotta get myself a dedicated macro lens!!
Just wow Steve! I see I have to go on a mission to build one of those mini tanks! Just super all around....comp, light, and clean up. Scary to think if they were our size! Now I know where they get the aliens for sci-fi movies!
Yikes! Wouldn't want to run into a human-scale one of these guys in a dark alley (or pretty much anywhere else)! As far as that goes, don't think I want to get too chummy with one the size of my little finger.
Another excellent image! Light, composition (agree square is perfect for this one), sharpness, DOF--you nailed them all. And I always enjoy the natural history lessons, as well. Just one question: If the adults range from 1 to 40 mm, how will this one reach 70 mm? You putting steroids or bovine growth hormone in that aquarium?
Thanks for the comments folks! I've been fascinated by these critters ever since I took an undergraduate field course in aquatic invertebrates many years ago.
Mitch - a little more life history - when this larva reaches full size it will crawl out of the pond and pupate nearby - hidden in the ground litter. Eventually, after undergoing complete metamorphosis, the adult beetle emerges looking completely different from the larval stage. This is not unlike a large-bodied caterpillar turning into a smaller-bodied butterfly.