Insects III - Doodlebugs, lacewings, cicadas and others
Read Morespp. Oak Ridge, TN August 9, 2008 This Antlion flew into the house as we were unpacking from our Bugguide Gathering trip. Great timing! :) I didn't want to scare it, so I photographed it on the floor. It is hard to believe that this used to be a gruesome "doodlebug" just a few weeks earlier! The adults are pretty, not as intimidating as their larval versions! It would be easy to mistake this for a damselfly at a quick glance because of its delicate wings and thin abdomen, however the eyes, mouth and curved antennae are good clues to its identity.
was chowing down on the Oleander aphids that were chowing down on my milkweed plants. The larva is about 1/2" long, so I had to use a 6 diopter adapter on my lens and then really crop this shot a lot! Some brown lacewing larvae stick small pieces of bark, lichen, or even the dried remains of their prey on their backs as a form of camouflage, they are called "trashbugs"!
Unfortunately, I had to break the Milkweed leaf to get to the underside in order to take this photo of a Lacewing larva eating an aphid (thus the drip of white sap). I had watched the larva stalk the aphid before it finally caught it. Note the fuzzy white debris it has put on its back as camouflage, it is probably the shed exoskeletons of the aphids. Talk about a "wolf in sheep's clothing"!
Cicada Nymph skin The discarded nymph skins (exoskeletons) are often found on trees, grass blades, or sides of buildings. The nymphs live underground anywhere from 7, 13, or 17 years, depending on the species. On some unknown cue, the nymphs begin to dig toward the surface and climb up a vertical surface. The nymph's skin splits on the thorax, just behind the head, then the adult insect slowly emerges from the skin. The process takes about 45 minutes (I watched one of the Dogday cicadas emerge from its skin once, it was fascinating!). After emerging from the soil-encrusted exoskeleton, the cicada rests and allows its wings to dry. The adult insects do not live long after mating. Reproduction is the "kiss of death" for these insects! They don't eat in this phase of their life, in fact, they don't even have a mouth!
While I was photographing this Syrphid fly larva eating an aphid, an ant suddenly ran over and tried to bite the larva! Ants obtain honeydew (a sweet liquid waste secretion) from the aphids, so they try to protect them from predators. She was not successful, but she sure tried! I wish the ant had not come out blurry, but the event happened so quickly I didn't have time to focus!
looks like a creature from a science fiction horror movie, but it is actually the larval stage of the Antlion. It digs a pit into loose soil, buries itself at the bottom and patiently waits for an ant to tumble in. My husband held this one in his hand so I could photograph it, fortunately it didn't bite him!(see next photo) A note of interest: doodlebugs can only move backwards!
Periodical Cicada; Magicicada septendecim
) is just one of trillions in the eastern United States that emerged from the ground in May 2004. It is a Brood X (as in "10" in Roman Numerals) Periodical Cicada, a.k.a. "17-Year Locust." They are un-nerving to "insectophobes," but these insects are harmless, they don't bite or sting. The males "sing" (a sound that has been likened to the whirring sound of a UFO landing in a Sci-Fi movie) to attract their prospective mate by vibrating two membranes on the thorax just below the first pair of legs. After mating, the female lays her eggs in slits in the bark at the ends of tree twigs. Sometimes the leaves on those twigs will wilt and die. Other than that, the insects don't harm the tree. When the nymphs hatch from the eggs, they fall to the ground below the tree and dig in the soil until they find a tree root to drink sap from. (to be continued on the next picture)
July 3, 2007 I found this brown Syrphid (fly) larva munching on these aphids on my milkweed leaves. These aphids are European transplants. The predator doesn't seem to be deterred by the bad-tasting toxin taken up by the aphids as they eat the sap of the milkweed. They use the bright orange coloration to deter predators.
Hemlock Wooly Adelgids; Adelges tsugae
Great Smoky Mountains NP May 10, 2008 I found this heavily infested tree while hiking in the Smokies. Unfortunately, these tiny, fuzzy, white insects can kill a hemlock tree quite quickly by sucking the sap from the needles and twigs. Many areas of the park have been devastated by these non-native insects. The park staff is fighting them by releasing small predatory beetles, spraying roadside trees with a soap solution and injecting large, off-road trees with an insecticide. Unfortunately, it is too late for many of the ancient hemlocks in the higher elevations of the park.
spp.) in these pits beneath the cliffs at Piney Falls. The larvae live in the base or the sides of the pits that they dig in loose, dry soil. When an ant falls into the pit, it is unable to walk up the loose grains of soil. Suddenly, the antlion grabs the ant with its' huge mandibles and pulls it beneath the soil at the base of the pit. Soon the ant is a dry shell, having had its liquids drained. Antlions are in the order Neuroptera, meaning "nerve-winged".
Giant Bark aphids; Longistigma caryae
Oak Ridge, TN June 12, 2009 I noticed these large aphids and even larger ants on a tree at the University of Tennessee Arboretum. The large black ants would stroke the aphids to encourage them to produce honeydew.