Xanthoteras teres
Weld, 1926
Ball-tipped Gall Wasp
Xanthoteras teres is a cynipid native to western North America. The induces distinctive on oak leaves, characterized by an upright stalk topped with a fuzzy spherical structure. Formerly classified under the Trigonapsis, it was reclassified to Xanthoteras based on taxonomic revision. The has been documented primarily in Oregon and California.



Pronunciation
How to pronounce Xanthoteras teres: //zænˈθoʊtərəs ˈtɛriːz//
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Identification
The induced by Xanthoteras teres is diagnostic: an upright, slender stalk rising from the leaf surface, terminating in a fuzzy, ball-shaped tip. This 'Suessian' distinguishes it from other cynipid galls on oaks in the same geographic range. The itself is small and typical of cynipid morphology, but identification relies primarily on gall characteristics.
Images
Habitat
Associated with oak woodlands and savannas where oaks occur. Found in supporting Oregon oak (Quercus garryana) and leather oak (Quercus durata).
Distribution
Oregon and California, western North America.
Host Associations
- Quercus garryana - Oregon oak; leaves are site
- Quercus durata - Leather oak; leaves are site
Behavior
Females oviposit on oak leaves, inducing formation. The resulting gall structure consists of an upright stalk with a terminal fuzzy ball.
Ecological Role
As a inducer, the manipulates oak tissue to form a protective structure for larval development. The galls represent a form of plant-insect interaction that creates novel microhabitats on leaf surfaces.
Human Relevance
No direct economic or agricultural significance has been documented. The distinctive may be encountered by field biologists, naturalists, and oak taxonomists.
Similar Taxa
- Other Cynipidae on QuercusOther cynipid induce on oaks, but X. teres is distinguished by its unique ball-tipped stalk . Linear, spherical, or irregularly lobed galls without this stalked structure are induced by different .
More Details
Taxonomic History
Originally described as Trigonapsis teres by Lewis Hart Weld in 1926. Subsequently transferred to the Xanthoteras, though the specific epithet teres was retained.
Sources and further reading
- BugGuide
- Wikipedia
- iNaturalist taxon
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