Polystepha q-nigra-vein-axil-gall

The inducer of this gall is unknown or undescribed.
Family: Cecidomyiidae | Genus: Polystepha
Detachable: integral
Color: brown, black
Texture: hairy, hairless
Abundance:
Shape:
Season: Fall
Related:
Alignment: integral
Walls: thick
Location: upper leaf, lower leaf, leaf midrib, at leaf vein angles
Form:
Cells:
Possible Range:i
Common Name(s):
Synonymy:
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image of Polystepha q-nigra-vein-axil-gall
image of Polystepha q-nigra-vein-axil-gall
image of Polystepha q-nigra-vein-axil-gall
image of Polystepha q-nigra-vein-axil-gall
image of Polystepha q-nigra-vein-axil-gall
image of Polystepha q-nigra-vein-axil-gall
image of Polystepha q-nigra-vein-axil-gall
image of Polystepha q-nigra-vein-axil-gall
image of Polystepha q-nigra-vein-axil-gall

Gallformers ID Notes

From above, these galls resemble the upper side of galls of Polystepha pilulae, particularly those with irregularly confluent rather than near-spherical structure. However, they differ in being found only in vein angles, in having a darker, almost black surface, and in having an enlarged hairy domatia on the lower side rather than a smooth callus. Observed in Florida in September.

A similar gall has been observed on the lower side of Quercus shumardii vein angles. Polystepha podagrae is known to make slightly smaller galls on veins and angles of Quercus ilicifolia and velutina.

- Gallformers Contributors: (2023) Gallformers ID Notes©


Further Information:
Pending...

See Also:
Unless noted otherwise in the ID Notes, observations of this gall are collected in the Observation Field Gallformers Code with value q-nigra-vein-axil-gall on iNaturalist. You can view them here:
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