Polystepha q-nigra-cone-gall

The inducer of this gall is unknown or undescribed.
Family: Cecidomyiidae | Genus: Polystepha
Detachable: detachable
Color: gray
Texture: hairless
Abundance:
Shape: conical, numerous
Season: Fall
Related:
Alignment: erect
Walls:
Location: upper leaf, between leaf veins
Form:
Cells:
Possible Range:i
Common Name(s):
Synonymy:
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image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall
image of Polystepha q-nigra-cone-gall

Gallformers ID Notes

An undescribed Polystepha species found on Quercus nigra and possibly other red-group oaks. It keys to P pilulae in Gagne 1989, with the gall on the upper leaf with only a small scar below, but differs in being much more narrow and conical, with a flat top, often appearing in numbers but not coalescing. The galls are gray-brown in color and have a slightly peeling surface that creates uneven rings around the circumference of the cone. Found from September to November.

Observations are collected on this page at BugGuide and in this Gallformers Code field on iNaturalist. The gall has been observed on Q nigra in MD, NC, FL, TN, AL, AR, LA, TX, GA, and SC.

A similar gall has been observed on Quercus imbricaria in September in Ohio (2) (3) (4), Missouri, and Indiana, on Quercus pagoda in October in North Carolina, on Quercus falcata in Texas in November, and on an unidentified oak (possibly also Q imbricaria) in September in Kansas (2).

- 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-cone-gall on iNaturalist. You can view them here:
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