Some cool bugs are out and about
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Apparently
the week of June 22 is “Cool Bug Week” because we got some dandies in
the lab. Jeanne (don’t know her last name) sent me a great photo of a
Cecropia moth that she was trying to identify. The Cecropia moth is one
of our most spectacular moths. The larvae feed on various broadleaf
trees and shrubs. The caterpillar is equally, if not more impressive.
This very nice photo of a Cecropia
moth was sent to us by Jeanne
For those of us who prefer the larval
stages of cute bugs, here's what a
Cecropia moth caterpillar looks like.
Photo credit: J. Ghent, USDA Forest Service. Courtesy of
forestryimages.org
A female whitespotted pine sawyer
beetle. Photo credit: S. Gower, MSU Diagnostic
Services
I
got a call from a concerned citizen saying he found Asian longhorned
beetles up by Ludington last weekend, which made me think that our
native Whitespotted pine sawyer, Monochamus scutellatus beetles have emerged. And sure enough, we got a very nice specimen from Norm Myers, the CED up in Oceana County.
Pine sawyers (Monochamus spp.) are the most common
“I-think-I-found-an-Asian-longhorned-beetle” that are sent into the lab
and for good reason, the resemblance is striking. See photos of the Asian longhorned beetle
to see what I mean. The Asian longhorned beetle is a highly destructive
exotic insect that has been in Chicago and New York, nobody here wants
to see it in Michigan, so send me anything that even comes close to
looking like an Asian longhorned beetle and I would be happy to look at
it at, no charge.
The genus Monochamus is represented by several wood-boring
beetle species in the eastern United States, all of which feed on
various conifers. The most common species in our area are M. scutellatus and the northeastern sawyer, M. notatus.
The larvae are known as "sawyers" because of the loud noise they make
while feeding. Freshly cut, felled, dying or recently dead trees are
preferred. Young larvae feed on the inner bark, cambium and outer
sapwood, forming shallow excavations called surface galleries that they
fill with coarse, fibrous borings and frass (insect excrement). As they
grow older, they bore deep into the heartwood, and then turn around and
bore back toward the surface, thereby forming a characteristic U-shaped
tunnel. A pupal cell is formed at the outer end of the tunnel, from
which the adult emerges by chewing through the remaining wood and bark.
Eggs are laid in slits or niches chewed in the bark, preferably near old
branch scars or in wrinkled areas on logs. Full-grown larvae are often
close to two inches long.
Two years are required to complete the life cycle in the Lake States and
southern Canada. Members of the genus often cause heavy losses in
wind-thrown or fire-killed timber, in saw logs left too long in the
woods or left too long with the bark on before milling, and in
improperly handled pulpwood. Adult beetles are vectors of Pinewood
nematode.
Norm also sent us an eyed click beetle or eyed elator, Alaus oculatus. This is another very handsome beetle and is our largest member of the click beetle family, Elateridae.
Its common name comes from the two large eye-spots on the pronotum. The
larvae, which may reach nearly two inches in length, live in moist,
decayed wood, especially stumps. The larvae are predaceous on other
insects. These handsome beetles are harmless.
