Silk-Button Spangle Gall Wasp

Neuroterus numismalis · Order: Hymenoptera · Family: Cynipidae

Also called: Silk-Button Spangle Gall

No source yet on danger. We have no source yet on whether it bites, stings or damages anything.
Silk-Button Spangle Gall Wasp
Photo: Victor Heng, CC BY

The silk-button spangle gall wasp lives on oak trees and makes many leaf galls. It has two generations to a bisexual one and a parthenogenetic one to each producing a different gall.

Source: Wikipedia

How to recognize it

The bisexual female is small, brown, with clear wings and hairy legs. The parthenogenetic female has a black pointed head, pale brown eyes, clear wings with dark veins and hairs.

Source: Wikipedia

Size

Bisexual females are about 1.8 to 2.4 mm long. Parthenogenetic females are roughly 2.5 mm long.

Source: Wikipedia

Where it lives

They live on oak trees, where they chemically induce leaf galls. A single leaf can hold over a thousand galls.

Source: Wikipedia

Life cycle

The species alternates between a bisexual generation and an agamic (parthenogenetic) generation, each forming a distinct gall type. Females emerge from silk-button galls in early spring, lay unfertilised eggs in oak buds, and cause blister galls.

Source: Wikipedia

When you see it

Females emerge from silk-button galls on the ground in early spring. The bisexual generation appears in midsummer from blister galls.

Source: Wikipedia

More photos

Silk-Button Spangle Gall Wasp photo 3
Photo: unknown, CC0
Silk-Button Spangle Gall Wasp photo 4
Photo: Paul Cook, CC BY

Same family (Cynipidae)

Mossy Rose Gall WaspMossy Rose Gall WaspDiplolepis rosaeHarmlessCalifornia Gall WaspCalifornia Gall WaspAndricus quercuscalifornicusCommon Spangle Gall WaspCommon Spangle Gall WaspNeuroterus quercusbaccarumCherry Gall WaspCherry Gall WaspCynips quercusfoliiWool Sower Gall WaspWool Sower Gall WaspCallirhytis seminatorOak Marble Gall WaspOak Marble Gall WaspAndricus kollariHarmless

Sources

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

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.

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