Giant Eastern Crane Fly
Sam caught this for me on August 8. I think she said it was on the outside of a window trying to get in. Anyway, it is a very large, striking crane fly with a wingspan of well over an inch. It’s unfortunately missing half of its legs, but that’s just the way things go with crane flies[1].
The abdomen comes to a sharp point, so it looks to be a female. Normally, getting a good ID on a crane fly is an exercise in frustration, because there are a bunch of species that look a lot alike. But, this one has the good fortune (for me) to both be very large, and to have distinctive patterning on the wings:
So, I feel pretty comfortable declaring her to be the Giant Eastern[2] Crane Fly, Pedicia albivitta, which seems to be the only crane fly species that has this particular pattern of wing coloration.
No posting about crane flies would be complete without pointing out the halteres that all of the Diptera have instead of a second pair of wings, if only because crane fly halteres are so very, very noticeable. Of course, I don’t really notice that they help the flying ability of a crane fly much, they still seem to spend a lot of their time bumbling around clumsily. That may just be because the long legs make them awkward.
Crane flies don’t have much in the way of either mouthparts or antennae. And actually, at first I wasn’t quite sure which head appendages are the antennae. Down in the comments, Biobob says that they are the ones that project sideways and look like a “Snidely Whiplash” moustache, and not the longer, multisegmented structures that project down from the face.
The Bug Guide entry says that their larvae are aquatic and predaceous, so I originally thought that they probably lived in our little micro-creek and ate black fly and mosquito larvae, among other things. So, I thought “Hooray!” But then, in the comments, Biobob said that they actually live in water-saturated soil or organic matter, and not in the open water where the mosquitos and blackflies live. And so, they never really encounter each other. Which is sad, but I’ll get over it.
Bug Guide doesn’t say what (if anything) the adults eat, but judging from their lack of obvious mouthparts, I’m inclined to go with “nothing, or nectar/sap”. Eating nothing is quite likely, because I doubt that they last long once they start to fly – they are clumsy enough fliers that they wouldn’t present much of a challenge to a bird in the daytime, or to a bat at night. Although, the legs might be of some benefit here. Anything trying to catch the crane fly is pretty likely to get hold of it by a leg rather than by the body or a wing. And then, the crane fly just has to shed the leg and scoot out of there to get away. As we can see from this one, they can perch just fine with only 3 legs (they don’t seem to walk much in any case), so that means they can shed up to 3 legs to escape predators before they get seriously inconvenienced.
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[1] Question on an introductory entomology exam: ” How many legs does a crane fly have”
Expected answer: “6”
Student’s answer: “Based on the specimens in our teaching collection, between 1 and 4.”
(Edit: I see that I’ve already used this joke – see footnote 2 in this post. Well, I thought it was funny.)
[2] Not to be confused with the Great Eastern, one of the first iron-hulled passenger liners (and for quite some time the biggest).
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“larvae are aquatic and predaceous, so they probably live in our little micro-creek and eat black fly and mosquito larvae”
The larvae are actually semi-aquatic and live in stream/lakeside water-saturated organic matter or soils and feed on anything they encounter and can subdue, including roots, decomposing organic material, worms, etc, depending on the species. They are very unlikely to feed on blackfly or mosquito larvae since their microhabitats do not overlap, as blackflies and mosquitos live in the water column and the water/substrate interface, as opposed to within the actual soil/organic matter burrowing habitat of crane fly larvae.
The whip structures are the antennae.
Thanks, Biobob. I’ve updated the post with your additional information.
The head almost looks like an afterthought.