June 11, 2015 at 5:52 am (dragonflies and damselflies, insects (other), plant-eating insects)
Tags: early zanclognatha, Erynnis juvenalis, Juvenal's duskywing, Laphria thoracica, Lestes australis, Mayslake, Rivula propinqualis, southern spreadwing, Spilosoma virginica, spotted grass moth, Virginia tiger moth, Zanclognatha cruralis
by Carl Strang
The warm weather has brought out a beautiful diversity of insect life at Mayslake Forest Preserve. Here’s the gallery from last week:
Early zanclognatha moths are appearing in good numbers this year in Mayslake’s woodlands.
Here is a second one, showing some of the variation in this species.
What they have in common is their relatively early season compared to similar relatives, a rather sharp bend in the dark line closest to the head, a kink or at least flat area in the tip of the curve in the middle line, and a rather straight outermost line. This is one of a large group of moths whose larvae make their living by eating dead leaves. Many are common in our woodlands thanks to that abundant resource.
This skipper put me through a long session with the references. I concluded that it is Juvenal’s dusky wing.
It is very similar to the wild indigo dusky wing, which also occurs at Mayslake, and I need to be more careful in the future in identifying these butterflies. The difference, as I understand it, is that Juvenal’s has areas of pale color within the black inner part of the forewing, and just inward of the central tan area there is a pale dot (very faint in this individual) rather than a short bar.
Less ambiguous is this Virginia tiger moth. There are other white tiger moths, but they don’t have the fancy black-and-white barred legs, a couple of which are sticking out here. Also, this one patiently let me move its leaf so as to get a look at its front femurs. They were yellow-orange rather than pink.
This pretty little moth, photographed near the edge of the north savanna, was an addition to the preserve species list. The spotted grass moth is described as “uncommon” in references.
Viewed dorsally, this Laphria thoracica robber fly is a very effective bumblebee mimic. At this angle, however, we can see how it is alertly watching for passing prey. The flattened abdomen, impressive predatory beak, and odd antennae prove that this is no bee.
First spreadwing damselfly of the year. The southern spreadwing is regarded by some as a subspecies of the common spreadwing.
June 28, 2009 at 9:29 pm (insects (other))
Tags: Ancyloxypha numitor, Celastrina ladon, Epargyreus clarus, Hobomok skipper, least skipper, Mayslake, Poanes hobomok, Polites themistocles, Semiothisa bisignata, silver-spotted skipper, spring azure, tawny-edged skipper, Zanclognatha cruralis
by Carl Strang
Recently I provided an update on damselflies and dragonflies that have become active at Mayslake Forest Preserve. New butterflies and moths also have been appearing. The large group of butterflies known as skippers can be tricky, but I believe I have these right: Hobomok skipper,
and tawny-edged skipper.
Both are, according to my references, common. I have found Hobomoks in other preserves early in the season. Even more common and distinctive are two more species, the least skipper
and silver-spotted skipper, the latter never far from black locust trees.
The most recent butterfly to show itself has been the spring azure.
Moths also are in evidence. This one, Zanclognatha cruralis, belongs to a curious group whose larvae eat dead leaves.
The following moth I photographed on the slope between May’s Lake and the friary, not far from a large white pine.
This one proved to be a tough ID. There is a large group of moth species which look very much like this one. Furthermore, many of these species show considerable variation among individuals. The yellow head and anterior thorax are unusual among them, I gather, and help to narrow down the possibilities. My tentative identification is Semiothisa bisignata, the caterpillars of which eat pine needles. In the future I may need to collect one or more of them. With some insects, photographs simply aren’t enough.