Tag Archives: silk

Graphopsocus cruciatus

Here’s a photograph of a narrow barklouse (Graphopsocus cruciatus) with a clutch of eggs. I was initially taking a photograph of the domed structure (more on that below), but then examined the photo on my camera’s LCD viewer and saw this tiny insect moving around. Which surprised me — it was December 18th, and cold. It wasn’t freezing, but certainly not a day I’d expect to find an insect out ovipositing. But apparently this group of insects (Stenopsocidae) are known to be active if there’s a random warm day in winter. I might go back in a few weeks to see what’s become of them.

Colin Purrington Photography: Insects &emdash; Narrow barklouse (Graphopsocus cruciatus)

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 such webbing, which tends to freak out homeowners. I’ve only seen that in Puerto Rico, though. 

Colin Purrington Photography: Insects &emdash; Clutch of narrow barklouse (Graphopsocus cruciatus) eggs

I’m not exactly sure what the egg case is (antmimic spider? ground sac spider?), but I’m wondering whether the barklouse might have positioned her eggs near a potential food source. 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 prefereces. I briefly thought the structure might be a slime mold like Enteridium lycoperdon, but then I saw (I think) white embryos or larvae through one of the two holes that seemed roughly chewed through the shell-like exterior. If you recognize the contents, I’d love to hear from you.

Colin Purrington Photography: Insects &emdash; Close-up of hole in egg case

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

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Planthopper parasite moth larvae

Here are some photographs of Fulgoraecia exigua, a moth that parasitizes planthoppers during its larval phase. There were dozens of these caterpillars at this location, many of them hanging by silk threads. They look like miniature sheep (a parasite in sheep’s clothing, I guess), and are rather cute, I think. But not for planthoppers, as you can probably guess. When the larvae hatch (earlier in the season) they crawl around and seek out planthoppers to latch onto, then suck their juices and eventually displace their hosts’ wings as the weeks go by. I.e., the planthoppers go about their lives with a caterpillar attached to their abdomens. When it’s done feeding the caterpillar lowers itself to the ground on a silk thread and pupates. I’m going to go back to the spot see if I can get photographs of the pupal form, which looks like a miniature version of the Sidney Opera House, built from the waxy fluff that protected them.

Colin Purrington Photography: Insects &emdash; Planthopper parasite moth (Fulgoraecia exigua)

Colin Purrington Photography: Insects &emdash; Planthopper parasite moth (Fulgoraecia exigua)

Colin Purrington Photography: Insects &emdash; Planthopper parasite moth (Fulgoraecia exigua)

Photographed on the Goshen Running Path, Newtown Square, Pennsylvania. Many thanks to Drs Roger Latham and Doug Tallamy for identification help.

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Spider versus wasp

I’ve watched hundreds of wasps hover around spider webs hoping to steal a meal or a spider, but rarely have I seen them foolish enough to get trapped. This was one was foolish. The spider was tiny, but approached the wasp every several minutes and threw a few strands of web on the wasp, then retreated. You can see the hind legs pulling out threads of silk. The wasp got away, by the way. Photographed at the Cornell Ornithology Lab in Ithaca, NY.

Colin Purrington Photography: Spiders and ticks &emdash; Wasp caught in spider web

Colin Purrington Photography: Spiders and ticks &emdash; Wasp caught in spider web

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