Thrinaphe hargeri

Thrinaphe hargeri · Order: Polydesmida · Family: Xystodesmidae

No source yet on danger. We have no source yet on whether it bites, stings or damages anything.
Thrinaphe hargeri
Photo: iNaturalist user, CC0

Thrinaphe hargeri is a sturdy millipede with a brown base color and a faint blue tint on its back plates. Its side extensions start low on the back and are deeply flattened, giving it a round shape from above, and it lacks bright warning colors, appearing uniformly colored. It is native to the Pacific Northwest, living in the Cascade Mountains near the Washington-Oregon border and down into the Willamette Valley.

Source: Wikipedia

Size

Thrinaphe hargeri is a robust millipede with a brown ground color and a slight bluish tinge to the tergites.

Source: Wikipedia

Where it is found in the US

Recorded in 2 of 51 states and DC. Most records: Washington, Oregon.

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

Source: GBIF

Months it is reported in the US

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Source: GBIF

More photos

Thrinaphe hargeri photo 2
Photo: iNaturalist user, CC0
Thrinaphe hargeri photo 3
Photo: iNaturalist user, CC0
Thrinaphe hargeri photo 4
Photo: David Anderson, CC BY
Thrinaphe hargeri photo 5
Photo: iNaturalist user, CC0

Same family (Xystodesmidae)

Black-and-gold Flat MillipedeBlack-and-gold Flat MillipedeApheloria virginiensisYellow-spotted MillipedeYellow-spotted MillipedeHarpaphe haydenianaCan irritate skinAromatic Cherry MillipedeAromatic Cherry MillipedeApheloria corrugataTraveling Cherry MillipedeTraveling Cherry MillipedePleuroloma flavipesXystocheir dissectaXystocheir dissectaYellow-and-black Flat MillipedeYellow-and-black Flat MillipedeApheloria tiganaCan irritate skin

Sources

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

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

Text written 2026-10-28 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-28.

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.