Discovering Minnesota’s Diverse Moth Species

**Phalaenophana pyramusalis** (dark-banded owlet, Family Erebidae, Subfamily Herminiinae).

How many moth species does Minnesota have?

When I first started moth hunting in 2017, I had no idea how many species of moths live in Minnesota. My first experience with Minnesota’s moth numbers was from a moth survey report. There had been a Minnesota DNR moth survey of state parks from 2006 to 2008 along the eastern edge of the state. Its purpose was to document moth species present before LDD moth (Lymantria dispar dispar) control efforts.

Their final list, representing just a small portion of the state, was 768 species, although they believed that statewide, there are about 2,200. I wondered how many of those moths might be where I live.

So many moths are tiny

Early on in my mothing I noticed there were many tiny moth species. I found some moths the size of a thumbtack. Others are smaller than a grain of rice, like the three species below.

*Epermenia albapunctella* (Epermenioidea)

Identification is not so simple

Most people are familiar with the larger charismatic moths, like the luna moth or one of the sphinx moths. But for many of the moths out there, they are just moths. This is understandable. Identifying anything to species is not always easy. With moths, this task is even more challenging given their variety of sizes, colors, and often subtle differences in wing patterns. To make matters worse, some species exist in different forms or look like other species.

Acleris (Superfamily Tortricoidea, Family Tortricidae) is a good example of a genus with intraspecific variation. Some species even resemble others within the genus. I’ve included two photos of Acleris celiana showing two of the forms it exists in. There are also photos of other Acleris species, some of which resemble each other.

So, is that the final count?

By the end of 2019, I had identified 541 moth species. It seemed to me this was close to the upper limit of moth species present. After all, the DNR survey had documented 768 species in thirteen state parks. These parks range from the southeast corner of the state to the northeast corner. I am looking at only a tiny fraction of that territory. About 40 acres, to be exact.

My list surpasses the DNR’s list

Eventually, my species checklist surpassed the MN DNR survey’s list. After rechecking identifications, synonymy, and duplications, my list was at 865 species. That’s 97 species more than the DNR list. How to account for that?

Accounting for the differences

The differences in species counts are most likely due to our respective sampling methods and time available. The MN DNR survey’s list is almost entirely species from so-called macro-moth taxa. It is heavily weighted towards Geometridae and Noctuidae.

It is likely that the smaller moths, the so-called micro-moths, were not within the scope of the survey. It would have taken too much time to identify every moth. This would delay the report and critical action on Lymantria dispar dispar expansion into Minnesota.

So, while our lists overlap for most of the macros, my list also includes micro-moths. These include those from the superfamilies Gelechioidea, Nepticuloidea, Tineoidea, Tortricidae, and other taxa with mostly minute moths.

When I am mothing, I try to photograph and later identify every moth that comes to my moth light. I am not under any time constraints to complete fieldwork or produce a final report. Some unidentified moths have sat in my photo files for years before I figure them out. They needed to present the bigger picture. I am just filling in the details and have plenty of time to do it.

My checklist will continue to grow

I’ve been working on documenting the moths on my land for eight years. I don’t think I am done yet. I also don’t think annual additions to my checklist have peaked.

The rate of new species additions has been about 33 per year since 2020. As of 2025, the species checklist stands at 865 moth species with 34 new additions. This includes macros and micros. If that rate continues, the checklist will reach 1,000 species in about four years.

Mothing into the fall and even the winter

Autumn is upon us now. Soon, almost all insect life outdoors will be gone. In the meantime, I will continue to photograph right up until the snow falls and the lakes freeze. But even in winter, it is possible to find some insect life, including moths, outdoors.

*Operophtera bruceata* (hunter’s moth) flies in late October. It continues into November when night temperatures typically drop into the 30s and upper 20s.

Carynota marmorata (marbled treehopper)

*Carynota marmorata* on American hazel (*Corylus american*a) catkins

Carynota marmorata (marbled treehopper) is a treehopper in the Membracides. This one caught my attention when I was getting ready to trim back a hazel bush that was extending a little too far into the driveway. I rushed back to the house, got my camera and tripod, and began shooting away.

Description

The high and rounded pronotal (the first segment of the thorax) crest is one of the first things that stand out on this species. The coloration of Carynota marmorata is variable but always a shade of chestnut-brown mottled with irregular greenish white speckling over the pronotum (the dorsal plate of the prothorax). Individuals may vary in the amount of speckling, with some having more than others. There may also be broad, more connected pale yellow patches forming transverse bands across the pronotum.

The pronotum is sparsely pubescent and coarsely punctate. The triangular head is sparingly pubescent, finely punctate, and spotted with red and yellow patches. They have red to black eyes. The tegmina have noticeable veins and are smoky hyaline. The legs are rust-colored, while the underside of the body is chestnut. Adults measure 4 mm in width and 8 mm in length.

Habitat and host plants

Carynota marmorata feeds on trees and shrubs in the birch family (Betulaceae), including paper birch (Betula papyrifera), American hazel (Corylus americana), and tag alder (Alnus incana).

**This hazel thicket in a mixed species (aspen, birch, spruce, fir) forest is habitat for **Carynota marmorata**.**

The Buffalo Treehopper: Characteristics and Habitat of Stictocephala taurina

*Stictocephala taurina*, the buffalo treehopper, on August 28, 2021, that was attracted to my moth lights.

Stictocephala taurina (buffalo treehopper, family Membracidae, in the order Hemiptera, the true bugs) is a green colored species of treehopper notable for its prominent, sharp horns. The horns on treehoppers have functions that include mimicking the thorns of plants and electroreception. According to the article in PNAS, treehoppers and their predators produce electrical fields, and the extreme morphologies of treehoppers aid in the detection of these fields.

Description

Stictocephala taurina is a green species of treehopper, one of 17 species of Stictocephala in North America north of Mexico. It measures about 7.5 mm long. The pronotum is adorned with two prominent horns on the front, numerous pale spots, and ends in a long spine. The horns are not very large and may have a dark edge. The legs are green (reddish in the similar-looking Tortistilus abnorma) and end with yellow tarsi (feet).

Habitat and host plants

Stictocephala taurina lives in forests and forested areas. The nymphs feed on softer herbaceous vegetation, piercing the plants to get sap. Adults move to woody vegetation.

Taxonomy

Class: Insecta (Insects)
Order: Hemiptera (True Bugs, Cicadas, Hoppers, Aphids and Allies)
Suborder: Auchenorrhyncha (True Hoppers)
Infraorder: Cicadomorpha (Cicadas, Spittlebugs, Leafhoppers, and Treehoppers)
Superfamily: Membracoidea (Leafhoppers and Treehoppers)
Family: Membracidae (Typical Treehoppers)
Subfamily Smiliinae
Tribe Ceresini (Buffalo Treehoppers and allies)
Genus Stictocephala
Species taurina (Stictocephala taurina)

Insects That Mimic Stinging Wasps: A Look at Synanthedon acerni

In a previous post, I wrote about syrphid flies that mimic bees and wasps. But are there other insects with this mimicry superpower? The answer is yes. Other types of flies, beetles, and moths all have species that mimic stinging insects. The moth Superfamily Cossoidea (Carpenter and Clearwing Moths) is notable for the many species that mimic stinging wasps.

Synanthedon acerni (Family Sesiidae, Subfamily Sesiinae, Tribe Synanthedonini) is one such very wasp-like moth. Its wasp-like appearance allows it to be active during the day while it visits flowers, feeding on nectar.

Life history

The larvae of Synanthedon acerni are not quite as benign. Known as the maple callus borer moth, its larvae bore into the trunks of maple (Acer spp.) trees. Eggs are laid near wounds in the bark. Entry into the tree is through these wounds on the tree’s trunk. The larvae bore into the bark and then into the cambium, where they feed on the inner bark and sapwood. Feeding takes place during the summer within galleries. In the winter, they hibernate in the galleries and resume feeding in the spring.

At maturity, the larva constructs an oblong cocoon of wood fragments, frass, and silk within the gallery, close to the surface, covered by a thin escape window. When ready to emerge, the pupa cuts open the cocoon and the escape window. The fully formed Synanthedon acerni moth then exits the pupa, which is left partially stuck in the gallery.

The same tree may be used year after year, weakening it and eventually leading to its demise. A callus will form on the trunk after repeated infestations.