A "fen" is a special kind of wetland that is a bit different from what one would call a bog or a marsh. I am no ecologist, so others should correct me if I'm wrong. As I understand it, fens have shallow water, but the water will circulate and that effects the pH and mineral content. So the flora and fauna of fens can be different from other wetlands.
There is a park about 15 minutes from my house called Seven Lakes State Park. I had long ignored it (too many people; too many kids) but that was wrong since there are isolated areas in the park that have
fens. Most of these are essentially inaccessible, but one is accessible if you know the Secret Way, which I had learned about a couple years ago. I never see anyone else there, which is perfect. So I had gone there several times, and here are pictures from some of the trips to my private fen!
On the way thru the deep woods, there was this unusual wasp-mimicking beetle (
Molorchis bimaculatis). Note the very short elytra. I've seen them before, but had never been able to get pictures since they are so nervous and twitchy (wasp mimics are like that). But this one stood still. Interestingly, its in the longhorn beetle family.
Wasp mimicking beetle by
Mark Sturtevant, on Flickr
Once out in the open, the fen alongside a particular lake becomes visible. There are several species of orchids in the park, and here is one of them – the tall and stately grass pink orchid,
Calopogon tuberosus. But far more interesting plants await.
Orchids! by
Mark Sturtevant, on Flickr
Out on the fen proper, the ground becomes firm sand that is always under about a quarter inch of water. Your shoes will get wet. And among the dense stands of coarse sedge grasses are three different species of carnivorous plants! Most obvious among them are the numerous pitcher plants,
Sarracenia purpurea. Early in the season, these have tall flower stalks with weird flowers. A feature of carnivorous plants is that they do not want to eat their pollinators, so they keep their flowers well away from their insect traps. I wonder if the weird shape of the flowers themselves are also designed to keep their pollinators from falling to their doom.
Pitcher plant by
Mark Sturtevant, on Flickr
Pitcher plant flower by
Mark Sturtevant, on Flickr
Crowding around the bases of the pitcher plants is another insect-eating plant, the sundews. These I think are
Drosera rotundiflora. They too will have flowers that try to not kill their pollinators, but I have not seen them in flower.
Sundew by
Mark Sturtevant, on Flickr
How those two carnivorous plants trap prey is pretty obvious and well known. The third carnivorous plant is more subtle about it. Dotting the landscape is a much scarcer but very distinct flower, and these belong to the horned bladderwort (
Utricularia cornuta). Bladderworts are more aquatic, and they have tiny specialized vessels that trap and digest small aquatic prey.
Horned bladder wort by
Mark Sturtevant, on Flickr
But for me, the real attraction of my private fen is a very special little dragonfly. These are elfin skimmers (
Nannothemis bella). Here is a female, and then a male. Elfin skimmers are the smallest dragonflies in the U.S., and also they are the second smallest in the world. The smallest is a close relative, found in China.
Elfin skimmer by
Mark Sturtevant, on Flickr
Elfin skimmer by
Mark Sturtevant, on Flickr
There are other fine places to visit in the park besides the fen. Alongside another lake nearby is a large gravely area, and one can always find lots of solitary wasps and tiger beetles there. Here is a big sands tiger beetle (
Cicindela formosa).
Big sands tiger beetle by
Mark Sturtevant, on Flickr
And because this too was at the park, here is a 4-eyed milkweed beetle,
Tetraopes tetrophthalmus. Their compound eyes are split by their antennae, so they have 4 eyes.
Four-eyed milkweed beetle by
Mark Sturtevant, on Flickr
Cheers!