I was out looking for the elusive snow fly yesterday but found this, instead: an eastern stonefly (Allocapnia recta), a member of the Capniidae (small winter stoneflies). At least that’s what I think it is. Larvae are active during the winter, and adults can fly and mate even when temperature is in the teens. Pretty incredible to see them flitting around on a cold day when other insects cannot even move. At Hildacy Farm in Media, PA. Probably emerged from the nearby Crum Creek.
Tag Archives: entomology
Copulating pair of Taeniaptera trivittata, a type of still-legged fly (Micropezidae). Males (or females, according to one source) apparently brush the eyes of the partner during mating, though this frame didn’t capture that. When flitting around leaves they wave their white-tipped forelegs and look just like small ichneumon wasps. They have thin waists but the pattern on their wings makes them look even thinner, waspier. Known to feed on rotting Typha, which was abundant nearby (John Heinz National Wildlife Refuge, Tinicum, PA).
If you come across a pair, please take a video so I can see the legs in action. I like to watch, and I know of others who are interested in this species.
Found a bunch of these flat-faced longhorn beetles on a dying tree a few weeks ago. I’m fairly confident it’s Astylopsis macula. But there are a gazillion genera of Lamiinae, so I’m happy to be corrected. Would also be very happy to hear from anyone who knows what elytral pits do, other than providing handy identification. I’ve wondered about that for years. Are they vestigial patterns from forewing ancestry? Sound-dampening trick to elude echolocating bats? Are pits just decorations, useful in crypsis or for intraspecific recognition? If you know, would love to hear from you.
Found two of these caterpillars on blackberry last week. I really should have brought them back home to see if they would eat morning glory leaves. Apparently they hate morning glory despite being named Schizura ipomoea (and thus traditionally called a morning glory prominent). Also sometimes referred to as the false unicorn prominent. You can distinguish the checkered-fringe from the unicorn prominent (Schizura unicornis) on the basis of head striping (among other differences). But don’t handle them during the identification process: they spray mixture of formic and acetic acid from that dorsal horn on abdominal segment one, and that will hurt and make your skin blister.
According to one study, these caterpillars coat the tissues of freshly-girdled tree stems with fluid. The authors guess that the fluid contains something that blocks the de novo production of chemical defenses in the leaves. This “chew and spit” behavior seems to be common in the family (Notodontidae). More details and papers on the behavior at David Dussourd’s website.
This is a newly-molted variable oakleaf caterpillar (Lochmaeus manteo), with old head capsule still attached. I initially thought the capsule was the head and that the thorax had eyespots, but John and Jane Balaban on Bugguide.net pointed out the obvious to me.
This species sprays formic acid, apparently.
FYI, Al Denelsbeck posted an almost identical image here, complete with close-up of the eyes.