Sigmoid Prominent

Clostera albosigma · Order: Lepidoptera · Family: Notodontidae

Also called: Sigmoid Prominent Moth

Damages trees, gardens or crops. The larvae can damage poplar and willow trees by feeding on their leaves.

Source: Wikipedia

Sigmoid Prominent
Photo: Reiner Jakubowski, CC BY-SA

Clostera albosigma, known as the sigmoid prominent, is a moth in the Notodontidae family. Adults have a wingspan of about 28 to 38 mm and are active from May to August depending on location. It occurs across North America from Newfoundland to Vancouver Island and south to Missouri, and its caterpillars feed on poplar and willow, which can harm those trees.

Source: Wikipedia

How to recognize it

Clostera albosigma is a moth of the family Notodontidae.

Source: Wikipedia

Size

The wingspan ranges from 28 to 38 mm.

Source: Wikipedia

What it eats

The caterpillars feed on poplar and willow leaves.

Source: Wikipedia

When you see it

Adults are on the wing from May through August, varying by location.

Source: Wikipedia

Where it comes from

Its native range covers the same North American region described for its habitat.

Source: Wikipedia

Where it is found in the US

Recorded in 44 of 51 states and DC. Most records: Vermont, Michigan, Minnesota, Massachusetts, New York, Wisconsin, Maine, Montana.

Darker = more records. Counts are museum and citizen-science records, not population size.

Source: GBIF

Status: native in North America; native in Canada; native in United States. Source: iNaturalist

Months it is reported in the US

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Source: GBIF

More photos

Sigmoid Prominent photo 3
Photo: unknown, CC0
Sigmoid Prominent photo 4
Photo: Stan Rullman, CC BY
Sigmoid Prominent photo 5
Photo: Colin Croft, CC BY
Sigmoid Prominent photo 6
Photo: unknown, CC0

Same family (Notodontidae)

White-dotted ProminentWhite-dotted ProminentNadata gibbosaDamages trees, gardens or cropsBuff-tipBuff-tipPhalera bucephalaDamages trees, gardens or cropsCommon Gluphisia MothCommon Gluphisia MothGluphisia septentrionisPine Processionary-mothPine Processionary-mothThaumetopoea pityocampaDamages trees, gardens or cropsWalnut Caterpillar MothWalnut Caterpillar MothDatana integerrimaDamages trees, gardens or cropsUnicorn ProminentUnicorn ProminentCoelodasys unicornisDamages trees, gardens or crops

Sources

  • Wikipedia: https://en.wikipedia.org/wiki/Clostera_albosigma

Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia

Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.

How this page works

This is one bug's fact sheet. The colored box at the top says whether it is dangerous. Sections below cover how to recognize it, whether it is a pest, and how to deal with it. The US map shows which states have records; tap a state to see other bugs there.

Every fact on Bug FAQ comes from a named source (university extension sites, government agencies, GBIF, iNaturalist, Wikipedia). The source is linked next to each section. If we have no source for something, we leave it out.