Fen Bugs

The purple coneflowers are just comijng into bloom

Saturday was my first visit to Bluff Spring Fen in a couple of weeks, and the insects have arrived in a big way. I did my first butterfly census route of the year, and recorded 12 species- a healthy diversity for this early in the year. While I was walking my census route I saw lots of other stuff, so I grabbed my camera and went out to record what was there.

There were abundant dragonflies and damselflies everywhere. I saw at least a dozen different species. All were beautiful, and many are common species. One, however, is listed as threatened in the state of Illinois. Bluff Spring Fen is one of only two Illinois sites where you can see the elfin skimmer. At just over an inch and a half wingspan, it’s North America’s smallest dragonfly.

Female (above) and male Calico Pennants (Celithemis elisa)

Pronghorn Clubtail (Gomphus graclinellus)
This is the first photo I've ever made of this species. I was unable to identify it as more than just a clubtail before today.

Eastern Pondhawk (Erythemis simplicicolis) - a study in green

Elfin Skimmer (Nanothemis bellus)

I got some nice caterpillar photos. The monarch seems a bit cliché, but I don’t care. This one was posing so nicely on the milkweed leaf that I had to take it’s picture. The other caterpillar is a Baltimore checkerspot- probably my favorite butterfly in the world. I did see a couple of adults this week. Very early in their flight period, it’s not uncommon to be able to see adults and caterpillars on the same day. The caterpillar here had been feeding on swamp betony, one of the plants that older larvae feed on. I expect to see many more adults over the next few weeks.

Monarch (Danaus plexippus)

Baltimore Checkerspot (Euphydryas phaeton)

Finally, there were tons of beetles around today. I only got pictures of a few species. Two that I’m posting here feed on milkweed. The milkweed longhorn beetle and swamp milkweed leaf beetle both advertise their toxicity by being bright red-orange. Also noteworthy was the reappearance of the clay-colored beetle, after a long absence. It was unintentionally transferred to Bluff Spring Fen during a plant rescue (I’ll blog about that another time). It feeds on only a few plants, including leadplant, a prairie species. Today, I found a half dozen individuals scattered about on various leadplants. I haven’t seen it on site in over ten year. Has it been hanging on at very low levels all this time, or did it recently re-colonize? We may never know.

Milkweed Longhorn Beetle (Tetraopes tetropthalmus)

Swamp Milkweed Beetle (Labidomera clivicollis)

Clay-colored Beetle (Anomoea laticlavia)
Not the best picture, but I'm thrilled that they're back.