Tag Archives: insect

Graphopsocus cruciatus

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Here’s a photograph of a narrow barklouse (Graphopsocus cruciatus) with a clutch of eggs. It was December 18th and cold, but apparently this group of insects (Stenopsocidae) are known to be active in winter.

Narrow barklouse (Graphopsocus cruciatus) with clutch of eggs. Domed object is spider egg case. Tinicum, PA.

Here’s a closeup of the eggs so you can see the silk that holds them down. I watched her apply this webbing (from labial silk glands) for about 15 minutes. Some species in this group are gregarious and can cover an entire tree in webbing.

Narrow barklouse (Graphopsocus cruciatus) eggs.

I don’t think the larvae will eat the egg case (a spider’s, I think). Barklice are reported to eat fungi, algae, lichens, plant tissue, and pollen, but there doesn’t seem to be much published on the species’ natural history or diet preferences.

Many thanks to Ross Hill (Meford, Oregon) for identification, and to Edward Mockford (University of Illinois) for helpful references on the species.

Copulating stilt-legged flies

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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).

Thanks to John S. Ascher and John F. Carr on Bugguide.net for help identifying them.

Checkered-fringe prominent

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Found two of these caterpillars on blackberry last week. 

Checkered-fringe prominent (Schizura ipomoeae) feeding on blackberry. Also known as the morning-glory prominent and the false unicorn prominent. Media, PA.

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.