Phylloxera caryaesepta (perforans)

Family: Phylloxeridae | Genus: Phylloxera
Detachable: integral
Color:
Texture:
Abundance:
Shape: conical
Season:
Related:
Alignment:
Walls: ostiole
Location: upper leaf, lower leaf, between leaf veins
Form:
Cells:
Possible Range:i
Common Name(s):
Synonymy:
Slide 1 of 2
image of Phylloxera caryaesepta (perforans)
image of Phylloxera caryaesepta (perforans)
image of Phylloxera caryaesepta (perforans)
image of Phylloxera caryaesepta (perforans)
image of Phylloxera caryaesepta (perforans)
image of Phylloxera caryaesepta (perforans)

North American Phylloxerinae affecting hicoria (Carya) and other trees

Phylloxera caryae-septum, var. perforans n. var.

A very conspicuous form of the above gall has been occasionally observed in the vicinity of Washington for several years past, occurring usually upon the leaves of Hicoria glabra, though always when already deserted. This same form had previously been observed by Dr. A. Fitch in the state of New York, also when deserted.

During May of 1890 1 have been fortunate, however, to discover this form in fair abundance upon a single tree of Hicoria glabra growing near a small stream in the vicinity of Arlington, Virginia, and widely separated by hills and gullies from trees bearing the genuine or typical gall. They contained (May 16th) besides the other forms a considerable number of the winged migrants which proved, after careful examination and comparison, to be absolutely identical with those of Ph. c. -septum. The causes of this remarkable and constant variation are not readily explained except by the fact that the typical form has so far always been found upon young trees with large and succulent leaves of Hicoria alba [Carya tomentosa], while those of perforans were upon trees of Hicoria glabra [Carya glabra] which had already attained a height of over twenty feet and with the leaves smaller and less succulent. As in the typical form, the gall is mostly single though now and then two, three or even more grow in close contact, generally close to the midrib, near its base, or near the stronger, cross-ribs, and, instead of expanding horizontally, they become narrow and considerably elongated above and beneath, resembling a slender spur or nail forced through the leaf. The length of the cones varies from 3-8 mm and the diameter at base from 2-4 mm. Both above and beneath, the cones usually lean to one side, those above usually in the opposite direction from those beneath, while cones growing near the edge of the leaf curve outwardly and often to such a degree that both points almost meet. Each cone splits into 6-8 slender bracts, fitting closely together and lined inside with a white, woolly pubescense.

At maturity the bracts of the upper cone separate to allow the insects to escape, while those on the under side remain closed. The inner structure of the galls is very similar to that of the typical form, though its walls are harder and thicker. Its color above and beneath is of a paler green than the surrounding leaf, incling toward the apex to purple or brown. The transverse ribs between which these galls are stationed are, at the point of junction, often considerably angulated, much thickened and of a beautiful red or crimson color.

- Theo. Pergande: (1904) North American Phylloxerinae affecting hicoria (Carya) and other trees©

Reference: https://www.biodiversitylibrary.org/item/114693#page/13/mode/1up


Further Information:
Pending...

See Also:
iNaturalist logo
BugGuide logo
Google Scholar logo
Biodiversity Heritage Library logo