Bugs without Bios XVIII
Bugs without Bios is dedicated to insects that stay below the radar (our radar, anyway) as they move through the world – they don’t make it into the field guides, and their internet presence is meager.
IPSILON DART MOTH
There’s actually plenty of information out there about the Ipsilon dart because its caterpillar loves to eat a variety of agricultural crops, but (except for one little twist) its biography is pretty straightforward. It’s one of those species whose adult and larval stages have different names – caterpillars are called Floodplain/Black/Greasy cutworms (one source described the larvae as greasy-looking), and another name for the adults is Dark Sword Grass Moth. It’s an Owlet moth (family Noctuidae) in the Cutworm/Dart moth subfamily Noctuinae, and its name comes from the roughly “Y’-shaped” markings on the wings and from a misspelling of the Greek letter upsilon, which corresponds with the letter “Y.”
The Ipsilon dart (Agrostis ipsilon) is a native moth that’s found across the continent into southern Canada and that has traveled around the world (except for very hot or very cold locales). It’s unwelcome wherever it goes because the caterpillar’s diet includes clover, corn, lettuce, potatoes, tobacco, alfalfa, strawberries, sorghum, sugar beets, cotton, and a variety of grains and grasses. If the eggs hatch before the crops sprout, the larvae sustain themselves on non-native roadside weeds like pigweed and curly dock and then move into the fields when they’ve finished the “weeds.” Adults feed on nectar. Here’s the life cycle https://bugguide.net/node/view/1225712/bgimage.
Although eggs are laid on low leaves, the caterpillars do their damage below the soil. There are multiple generations per year in the South; one or two in the North; and the last brood overwinters as pupae. And here’s the twist – in the northern half of its range, winters are too cold for the pupa to survive. Adults from the final generation in the north head south to escape the cold (southbound moths don’t reproduce), and in spring, moths migrate north to escape the heat. According to “Featured Creatures,” a great newsletter of the Entomology and Nematology Department of the University of Florida, “moths collected in the central region of USA in March and April are principally dispersing individuals that are past their peak egg production period. Nonetheless, they inoculate the area and allow production of additional generations, including moths that disperse north into Canada.”
There are so many Ichneumon wasps out there – according to bugguide.net, an estimated 60,000 species worldwide with possibly 40,000 more to discover and describe – so many species that even among those that are named, their life stories are incomplete. They come in all sizes, shapes and colors; their larvae make a living by parasitizing other insects and even some spiders (and they tend to be very specific about their targets); and they (mostly) don’t sting.
The BugLady was trying, unsuccessfully, to identify this handsome wasp; she finally asked for help (thanks, PJ), and it turned out to be an Ichneumon wasp. The BugLady is disappointed that the shiny new wasp book she bought doesn’t cover the Ichneumons, but if it did, she probably couldn’t lift it.
Ichneumon annulatorius (no common name) can be found in the northeastern quadrant of North America, from Newfoundland to Virginia to Iowa. Not a lot is known about it, but some of its life history has been inferred from observations of its close relatives.
In a 1971 article in the Ohio Journal of Science called “Hibernating Ichneumonidae of Ohio.” Clement Dasch points out that in spite of the fact that ants, bumble bees, and some paper wasps overwinter as adults, hibernation is a relatively uncommon habit in the Hymenoptera (ants, bees, and wasps). Yet, while looking for hibernating wasps in Ohio, 39 species of Ichneumonids were collected.
Insects pick their hibernacula carefully, aiming for high humidity and minimal fluctuation in temperature (sunny spots are out). Ichneumons most frequently chose places under the loose bark of fallen trees on north-facing (shaded) slopes, close to the ground, or in deep ravines. Other sites included the soft, rotten wood of an old stump or dead wood that was heavily tunneled by other insects. Some species – including Ichneumon annulatorius – liked thick growths of moss on rocks or trees. Favorable sites often housed multiple wasps.
Of the 5,275 wasps he collected, Dasch found only a single male – these species produce a single generation per year, and males died after mating in fall. Pregnant females entered hibernation by late October and emerged in early April when the air temperatures stayed above freezing, and when they emerged they immediately looked for a host to lay eggs on/in.
GRACEFUL SEDGE GRASSHOPPER
The BugLady was in the Bog on a fine fall day in 2015 when she spotted this jumpy grasshopper on the boardwalk. It allowed two pictures and then departed. The BugLady searched unsuccessfully for a grasshopper with the combination of striped head and thorax, glorious red on the femur, and white band on the tibia, and she finally sent it out to a grasshopper expert (thanks Chuck!).
The Graceful sedge grasshopper (Stethophyma gracile/gracilis), aka the Northern sedge grasshopper/locust (in the short-horned grasshopper family Acrididae) occurs across southern Canada and the northern US, as far south as New Jersey and Nebraska. It was probably more common 100 years ago, and bugguide.net speculates that it “seems to have disappeared from much of its southern range.” It’s considered widespread but local, favoring sedge meadows, brushy swamps, stream edges, and other sunny, wet areas, and in the West, it prefers cool uplands. The grasshoppers live in and eat sedges.
According to an article called “The Orthoptera of North Dakota” in the Proceedings of the Academy of Natural Sciences of Philadelphia (Vol LXXXVII 1925), “it reaches maturity late in the season and is not apt to be found adult before the first of August……”though the males are active, fly vigorously and stridulate loudly, the heavier females are less easily found, then usually ready to leap down into the thickest tangle of grasses at the first alarm.” The BugLady found an article that suggested that when male grasshoppers stridulate (make noise by rubbing one body part against another) they are more likely to be talking to other males than wooing females.
Kate Redmond, The BugLady
Bug of the Week archives: