Showing posts with label Ambush bugs. Show all posts
Showing posts with label Ambush bugs. Show all posts

Friday, December 14, 2012

Old Entomological texts are the best

Seriously. I'm not sure if it's just because I'm reading papers published a hundred years and the context of the written text is different from what I'm used to today or what, but there are so many great paragraphs hidden away in yellowing papers that are now digitized. A great resource for these papers is the Biodiversity Heritage Library, a cooperative effort by libraries to digitize biodiversity records and make them available online--for free.

It has great search features and has provided me with a lot of great information that I wasn't able to find anywhere else. It's also a nice resource for finding beautiful old pictures of plants and animals, which led me to search it today for a picture of the wheel bug. Instead, I happened upon a page from a circular released by the United States Department of Agriculture, Bureau of Entomology in 1904.

Instead of finding info about the wheel bug, I found a paragraph written by someone who did not like ambush bugs:
"A small, evil-smelling plant-bug, Phymata wolffii Tal. (fig. 6), secretes itself in flowers, such as thistle and goldenrod, and destroys numbers of the butterflies, capturing them and sucking out their vital fluids."
You just don't get that kind of bluntness nowadays; it's refreshing. The butterflies the circular is referring to are individuals of the imported Cabbage White Butterfly (Pieris rapae), if you were wondering.

For your viewing pleasure, figure 6 is below. Keep in mind that this little ambush bug is only about half an inch long.


Sunday, August 26, 2012

Late Summer Insects: Now showing!

Summer's starting to wind down (despite the temperature still hovering around 90 degrees on a daily basis), and that means new insects are now starting to make their appearances. One of my favorite groups are the assassin bugs, family Reduviidae, and late summer happens to be one of the best times to study them. Ohio's most charismatic species reach adulthood during this time, including the wheel bug (Arilus cristatus) and the jagged ambush bugs (genus Phymata).

The ambush bugs are small, stout assassin bugs in the subfamily Phymatinae. The family contains three genera in North America, and the most commonly-seen ones are in the genus Phymata. The subfamily hasn't received as much study as the rest of the assassin bugs, so your best bet for identification is to check out BugGuide's page. Dan Swanson has done some great work to figure out how to identify the Phymata spp., but it can still be tough.

A jagged ambush bug, Phymata sp., awaiting its next victim on wingstem.

Where are the best places to look for ambush bugs? Wherever the fall wildflowers are blooming. Roadsides and sunny fields are good bets, and it's usually worth your time to check out plants such as Queen Anne's Lace (Daucus carota), Goldenrod (Solidago spp.), Ironweed (Vernonia spp.), and Wingstem (Verbesina alternifolia). Ambush bugs prefer to creep around flowers, waiting for other insects to come in and land on the flower heads, and that's when the bugs grab them. Like other assassin bugs, ambush bugs have a proboscis they insert into their prey and use to pump in digestive enzymes. The bug will then stay a while, drinking up their milkshake.

These bugs come in a variety of colors: the picture above shows an ambush bug that's yellow with some green on its abdomen, but this can vary. These bugs exhibit some convincing camouflage, and if you want to find one on goldenrod, you may have to search for a while.

A golden ambush bug, Phymata sp.

Camouflage doesn't always help these bugs, however. You might not be able to see them, but sometimes you'll see their prey held, unmoving, above the flowers. Since dead insects don't have the power to levitate, you can be sure a predator is underneath, having a feast.

You may also encounter another vicious predator while walking through fields during this time a year, though you would barely know it as it flew by.

A gnat ogre, Holcocephala sp.

Believe it or not, the above fly is a robber fly, in the family Asilidae. Robber flies can be over an inch long, but this particular genus contains three species in Ohio, all of which could fit on your pinky nail. They're formidable foes of small insects such as gnats, small bees, and wasps, and are territorial. These ogres don't fear much, least of all humans, which allows people to get up close and personal with them. Macro lenses come in handy here. If the gnat ogre flies off before you can get your shot, just wait a while--it will probably come back and land on the same blade of grass in a few seconds.

There's a lot more out there waiting to be found, and many insects will disappear for the season while others start to emerge. If you want to see the beautiful Eastern Cicada Killer wasp, (Sphecius speciosus), for example, you only have a few more weeks left before it's gone for the year. Get outside and start looking now, before it's too late!