Last Moths of the Year?

Possibly. Temperatures at night have gone below freezing four times since mid-September which has put an end to the songs of crickets and grasshoppers. Bees and butterflies are gone, either killed by the cold weather or hibernating. But in the last six days, I’ve seen a moth, Operophtera bruceata (Bruce Spanworm), flying in the woods. Operophtera bruceata is a brownish moth with faint markings and is in the Geometridae. On Thursday and Friday, I turned on my porch light and attracted about 25 moths each night. That’s the largest number of Operophtera bruceata I’ve ever seen at one time so this must be a boom year for them. Saturday and Sunday nights saw fewer moths and on Monday there were none.

Operophtera bruceata spends only a few weeks of its life as a moth. From late fall to May it is an egg hidden in cracks and crevices in tree bark waiting out the winter. In May and June, the larvae hatch and begin feeding. The larvae feed on a variety of common tree species but prefer aspen, sugar maple, beech, and willow. Pupation lasts until October.

Operophtera bruceata exhibits sexual dimorphism with winged males and wingless females. Apparently, this strategy works well as the moth is widespread in North America.

Other moths are also appearing at the lights. One is Lithophane grotei (Grote’s Pinion) which has only recently eclosed. It will not mate until next spring. Instead, Lithophane grotei will find shelter under bark or woody debris to hibernate and wait out the winter. A different life strategy from that of Operophtera bruceata. Its larvae feed on maple, birch, cherry, and apple leaves. Lithophane grotei is widespread in the northeastern US and Ontario and Quebec in Canada.

A third species at the lights was Sunira bicolorago (Bicolored Sallow). This species is common over most of the US and southern Canada east of the Mississippi River in moist forests. The larvae of Sunira bicolorago are generalist feeders of many herbaceous and woody plants and not just willows as its common name might suggest.

The fourth, and perhaps the final moth of the year, I saw was Xanthia tatago (Pink-barred Sallow). Like Sunira bicolorago, it occurs in moist forests where willows and cottonwoods grow as it is a food specialist and feeds exclusively on plants in the willow family (Salicaceae). Early larval stages feed on the catkins of willow (I can’t find any information about feeding on cottonwood catkins) and later on the leaves.

Weather forecasts over the next two weeks show decreasing day and night temperatures with highs rarely reaching the 50s and lows down in the 20s. Not unexpected weather for this time of the year. On sunny days some tiny moths or caterpillars might be out but evening mothing is probably over until March next year at the earliest. But that’s not set in stone as on December 15 last year there was this sighting of an Acleris sp. (possibly Acleris busckana). In the meantime, until temperatures are consistently at or below freezing, there will be other insects, spiders, and other small arthropods out and about waiting, I hope, to be photographed.

SOURCES CITED

Bug Guide:

Operophtera bruceata

Lithophane grotei

Sunira bicolorago

Xanthia tatago

Pacific Northwest Moths:

Sunira bicolorago

Xanthia tatago

Moth Photographers Group:

Operophtera bruceata

Lithophane grotei

Sunira bicolorago

Xanthia tatago

Sword-bearing Conehead

My mothing nights find more than moths. Beetles, bugs, flies, wasps, spiders, and crickets, even snakes and frogs, are frequent visitors to the porch light. The latest non-lepidopteran to make an appearance is the sword-bearing conehead (Neoconocephalus ensiger). It is a new addition to my insect checklist and is one of five species of¬†Tettigoniidae¬†(Katydids) that I’ve identified from here.

The sword-bearing conehead is a large insect with males growing 4.5 to 5.5 cm, and females 5.2 to 6.4 cm. The head is conical with the sides pinched-in and black below. The body’s lower surface is edged in black. The stridulatory vein, which is used to make the call song in males, is long and weakly swollen. The ovipositor is blade-like and nearly the length of the body hence the name “sword-bearing”. Two color forms, green and brown, exist.

The call song of the sword-bearing conehead is a series of rapid tsst-tsst-tsst sounds. At higher temperatures the call song is faster. Singing begins at dusk and may continue all night if temperatures are warm. Singing Insects of North America (SINA) and Songs of Insects have recordings of this species and others on their websites.

Sword-bearing conehead is common across much of the eastern and north-central US and ranges as far north as Manitoba, Ontario, Quebec, and New Brunswick in Canada. Habitat includes damp grassy areas, roadsides, and weedy areas where they feed on grasses and sedges including the flowers and developing seeds.

Range map of the sword-bearing conehead.

SOURCES

Bug Guide
Singing Insects of North America
Songs of Insects

A tremendous increase

Digrammia mellistrigata
One of the latest additions to the checklist is Digrammia mellistrigata (yellow-lined angle) a moth in the Geometridae (inchworms).

Since I last posted on the moth species diversity (a very long time ago) the list has gone from 270 to 761 species and will very likely continue to grow until winter puts a stop to insect activity outdoors. Some species were to be expected as they are common and widespread but there have been nights and a few days with interesting surprises. Eventually, the number of new additions will level off and then fall as the actual number of species is approached. But for the next year or two, about 50 new species will probably be added each season. Just in 2022 I’ve added 50 more species with July being the best month with 21 species. I’m not going to go through the whole list of new additions but below is a small sample of my favorites from the last few years. In some future posts I’ll be covering some unusual species occurrences while others will cover groups such as new Geometridae or new Crambidae I have found.

2018

Cucullia convexipennis larva
Metanema inatomaria

2019

Dejongia lobidactylus
Datana ministra

2020

Epermenia albapunctella
Acronicta lepusculina larva

2021

Schinia septentrionalis larva
Darapsa choerilus ( Azalea Sphinx Moth)

2022

Elophila ekthlipsis
Plagodis phlogosaria

I think it’s about time to revive this blog

Well, I’ve been away for quite some time now. A lot has been happening here where I live and my life has gone through some changes. The biggest change is that I have officially retired. This happened right around the time of the COVID lockdown. Great timing, right?

This past July I finally got to take that vacation I was going to do in 2020 car camping and hiking in the Superior National Forest. That is one of the places where I used to work but this time the pace was relaxed and it didn’t matter if everything on the agenda was completed or not.

A micro-moth I found on the Superior Hiking trail in Lake County, Minnesota. It might be Landryia impositella or maybe a species of Scythris. Whatever species it is this moth is nectaring on big leaf aster in a sugar maple/paper birch forest.

I’ve also been doing a lot of exploring where I live and have found many more species of moths, one of my latest obsessions, as well as lichens, fungi, plants, and other living things. Back when I stopped posting the moth checklist was at about 470 species. Now, it is at 763 species and will probably go even higher before the winter weather arrives in late October.

Apantesis phalerata (harnessed tiger moth) one of the new moth species discovered this year at my porch light. Its presence marks a significant range extension north.

I’m building up the checklists on other insect species, too. While not as large (yet) as the moth lists they have been steadily growing. My focus is on bugs, beetles, wasps, and bees which is enough for now. Down below is one example of the new beetles on the checklist, Chlaenius tricolor (ground beetle), which under certain light conditions has a metallic iridescence. More will be coming soon.