Neuroterus evanescens

Quercus breviloba
Flower galls
A swelling, 5 mm long, of the staminate axis in early March, TX. Adults emerged Apr 4 and oviposited on under side of leaves. Entered from lit.

[Photo caption (no photo)]
Q breviloba. Gall an enlargement of the staminate axis similar to Fig 289 but shorter. Adults began to emerge Apr 4 and were observed ovipositing on under side of the leaves. Entered from lit.

Neuroterus evanescens, new species

GALL. — Very slight swelling of the stem of the ament, causing an abortion of the whole ament into a short, ovoid mass about 5. mm. long, covered closely with clustered but otherwise normal anthers. The larval cells are tiny cavities in the swollen stem, without distinct linings, covered on the outside by only very thin tissue. On aments of Quercus breviloba.

RANGE.— Texas: Austin (Patterson).

Only two males were obtained among the fourteen adults, but it is not unlikely that the sexes are usually more nearly equal in number. Patterson reports the galls appearing early in March, and the adults beginning to emerge March 15. With such a short life history for this generation, another form must occur in the remainder of the year. A bisexual generation on such an evanescent part of the host usually produces the alternate, agamic generation on some other part of the same host, and Patterson has observed the females ovipositing on the under sides of the leaves. The gall material of the Patterson collection number 68 occurs on Q. stellata ; it shows only a slightly greater degree of swelling of the stems, but when the insects are obtained it may prove a distinct variety confined to the single species of host.

Neuroterus vernus variety evanescens bisexual form

GALL. — A swelling of the ament stem, forming a mass about 5 mm. long; on aments of Quercus breviloba.

RANGE. — Texas: Austin.

A couple of corrections should be made in the data I originally published with this insect. The types should bear the Patterson number 68 ; the galls appeared about March 19, and the adults began emerging April 4, 1922. Patterson observed the insects ovipositing on the under sides of leaves, and since the variety is so closely related to the varieties which produce leaf vein swellings, there is little doubt that the agamic generation will be found in such a gall. The Patterson material occurring on Q, stellata should be numbered 46. This may represent a distinct variety.