Jul 8, 2017
So, Selene and I were walking out to lunch in downtown Augusta the other day when we saw a nice male Dobsonfly. They fall into the category of "charismatic megafauna" (almost) and it struck me as a good time to add some pics so you could know what we were talking about in Episode 5.
Interestingly, Episode 5 has consistently been the least downloaded episode - probably because no one knows what Megaloptera is! But they are cool - as you can see from the pics.
Here's the guy we collected at lunch:
Here's a picture that shows the scale:
We talk about those jaws in the podcast - but while scary looking they are actually not too effective. This guy waved it around but I actually couldn't get him to pinch me.
In contrast the females have short stout muscular jaws, which can, in fact, give you one heck of a pinch. Here is a close up of one specimen from my collection (unfortunately, she has lost her antennae, which is why she looks a little funny):
As I discussed in the podcast, the larvae are often called Hellgrammites - and they too, can give you a heck of a pinch. They are the top insect predators of the trout stream - gobbling up whatever they can, stoneflies, mayflies and the occasional angler. Here is a top down pic, which, while the colors are washed out, it gives you a sense of the structures on these guys:
A better pic is from this fellow, who lived in my tank on my lab desk for awhile. I like these pictures because you can see the clear color contrast between the tan leathery abdomen and the shiny chitinous thorax and head.
Closely related to dobsonflies are fishflies (and those larvae may be fishfly larvae - I didn't bother to count the filaments on the abdomen!). The adults (and larvae) look generally like dobsonflies but the adults don't have the serious mandibles and are generally smaller. They also have combed antennae rather than the filamentous antennae of dobsonflies.
and without spread wings:
There is are also a few species found on the east coast that look very different than this typical grey color. These guys are in genus Nigronia and they look like this:
To give you a sense of scale:
Lastly, but not leastly, are the alderflies. These guys fall within the same order (Megaloptera) but are smaller and are often mistaken for caddisflies on the wing. The easiest way to distinguish between the two is that the alderflies have membranous (rather than hairy) wings, and have a broad thorax behind the head - giving them a football player kind of look.
Anyway- that's Order Megaloptera. Hope you found this useful.