Disholcaspis quercusmamma

Pointed bullet gall. Similar [to Disholcaspis quercusglobulus] but pointed at the apex, subclasping at base, often distorted by crowding and extending along the stem for several inches sometimes. Frequently on sprouts from stumps or on small trees in large numbers in the fall. On Q. macrocarpa and bicolor. Adults emerge Oct. 20-Nov. 10.

Disholcaspis mamma (Gill.)

This gall may be confused easily with the preceding [Disholcaspis quercusglobulus]. The distinguishing characters are a velvety surface and pointed apex. It usually occurs in large numbers and in variable sizes on the branches of the burr oak, Quercus macrocarpa.

Color: green, turning brown.

Holcaspis duricoria

H bassetti as compared with H duricoria, is rather larger and more irregular in outline. The teat-like projection is much heavier and longer in proportion to the size of the gall and appears to be a drawn-out portion of the substance of the gall, while in duricoria it is a small, hard pointed projection much resembling a spine in many cases, and often almost entirely wanting. In bassetti the substance of the gall is more corky and easy to cut. The central cell, as before stated, is at the base of the gall, and when the latter is removed the point of the cell can usually be seen protruding below. Before the gall is detached the central cell is situated with its greatest diameter perpendicular to the limb at the point of attachment of the gall. In duricoria the cell is situated at the center of the gall; it never protrudes from below when the gall is detached; and it always has its greatest diameter parallel with the limb at the point of attachment of the gall. The central or larval cells are also differently shaped. In duricoria the cell is egg-shaped, while in bassetti the end towards the twig is somewhat pointed, so that the cell is very much the shape of a plump apple seed with the point rounded off.

Disholcaspis mamma

Quercus bicolor, lyrata, macrocarpa
Stem galls, detachable
Pointed Bullet Gall. Green to reddish, darker at apex, covered with very short pubescence, in fall.

[Photo caption]
On Q bicolor. Also on Q lyrata, macrocarpa. Adult in Nov (IL)

Disholcaspis quercusmamma (Walsh and Riley), 1869.

Cynips quercusmamma
Holcaspis mamma
Diplolepis quercus macrocarpae
Holcaspis duricoria
Holcaspis duricaria
Cynips macrocarpae
Andricus macrocarpae
Andricus quercus-macrocarpae
Disholcaspis quercus-mamma
Disholcaspis quercusmamma

Hosts: Quercus macrocarpa, lyrata, bicolor

Range: throughout eastern and central North America, from southern Manitoba, east through New Brunswick, throughout the eastern USA, and as far south as northern Florida and eastern Texas. However, the range of D. quercusmamma potentially extends anywhere that potential host trees have been transplanted outside their native ranges, if the insects were also translocated (e.g., Edmonton and Fort Collins).

Disholcaspis mamma

Galls on Quercus macrocarpa are here recorded from the following localities: Mandan (H. F. Bain), N. Dak.; Walnut Grove (C. J. W.) and Becker (L. Haney), Minn.; Evanston, New Lenox, Glen Ellyn, and Moline, IL.; Corinth (C. Barracks), Iowa; Cedar Point, Kan.; Nebraska City, Nebr.; Surry (C. Chupp), and Waterloo, Ind.; Manistee, Mich., and Medina, N, Y. On Q. bicolor at Evanston, IL. On Q. lyrata similar galls yielding similar adults at Hoxie and Texarkana, Ark., and Poplar Bluff, Mo.

In the Chicago area the galls start about the middle or end of July and some are full grown by end of August, adults emerging in different years from October 20 to November 10. At Poplar Bluff galls contained pupae October 8 and adults emerged November 13- December 3. Brodie found the galls at Toronto on Q. macrocarpa, the adults emerging in 1896 from October 17 to November 6. Some lived until November 22, but they do not survive the winter. In order to determine the next season's galls he "put 25 females in a muslin bag tied around a couple of low branches of burr oak from which the leaves had fallen on November 10 and for some days noted them ovipositing. They stood upon the tops of the buds grasping them firmly, then curving up the abdomen they pushed the ovipositor between the scales of the buds and remained a few minutes but they do not place more than one to three eggs in a bud." On May 30, 1897, he found numerous galls, the petiole or midvein beginning to bulge. By July 1 they were full grown and adults emerged July 11-17. "These galls were similar in form and texture to galls of H. petiolicola from white oak, contained from 3-10 cells, the producers emerge in the same way as A. petiolicoIa. Producers sexual, sexes about equally numerous." So far as the writer is aware this is the first published indication of an alternating generation for a Disholcaspis — a genus whose species are all known by agamic females emerging in the late fall.

Cynips quercus mamma [new species proposed but not thoroughly described]

[footnote]

See Proc Ent Soc Phil III, p 639, note. The gall resembling the oak-bullet gall (Q globulus Fitch) which is there mentioned as occurring on Burr oak, has been since ascertained by us to be produced by a distinct species of Gall-fly from that which produces the oak-bullet gall. The gall itself has the same very remarkable internal structure, but differs externally in being somewhat rougher and in usually having a little nipple at its tip, whence we may call it the oak-nipple gall (Q mamma). The fly, like that of the oak-bullet gall, occurs only in the female sex. Thirty-eight specimens, all females, came out from galls of the same year's growth Oct 22 to Nov 7. It may be called Cynips q. mamma, as it is an undescribed species.

Disholcaspis mamma

Globose, obscurely pointed, green, bright red, turning to brown or dark red, diameter 6 to 18 mm, on Q platanoides [bicolor] Q macrocarpa.

Disholcaspis quercusmamma

Twig gall. Light tan globular woody gall with a rough surface, found in groups of 3 or more. Bur oak. Summer.

Holcaspis duricoria, n. sp.

Galls. — Globular, but less regularly so than H. globulus Fitch; sessile and subclasping on the young branches of Q. bicolor. The flattened base and the cone-like form of many of these galls remind one of the Minnie rifle ball. They are often so crowded that they become strangely misshapen; the surface is finely pulverulent, and when dry it is very hard. This suggested the trivial name. Internally the substance is similar to, but much harder than that of H. globulus. The larval cell is free in a small, irregular cavity; the galls average one-half inch in diameter, and the oval larval cell is one-eighth by three-sixteenths inches.

They are sometimes found in countless numbers on a single tree and for a single season, and then nearly or quite disappear. A few galls of this species appeared several years ago on a large and thrifty oak (Q. bicolor). which is growing in the yard of one of my neighbors. The next year the tree was covered with them; there were bushels of them, but the year following there were few, if any, new galls, but this year they have appeared again in considerable numbers. In this instance, and a few others, I have noticed that the tree seemed to be quite seriously injured by them. It is well known that this species has a large number of parasitic enemies, else it might prove very destructive to this species of oak. It has other foes besides insect parasites.

This is an agamous species, and I flattered myself that the tree in my neighbor's yard would give me an excellent opportunity to study the habits of these female flies as they left the galls, which they do in October and November.

I went day after day to look for them, but found only now and then one on the palings of the fence enclosing the yard. At length I discovered that several English sparrows and other small birds of different species had taken possession of the tree and were devouring the insects as fast as they appeared. I saw a species of creeper peer into a cluster of galls and seize a fly before it was out of the gall. Of course my effort amounted to nothing, and the mystery around the second generation remains, so far as I know, still unsolved.

That birds peck open galls of various species for the larvae they contain is well known to every entomologist.

Though this species has long borne the above name, given by me as a manuscript designation, it has not till now been published. Intending at the time to publish immediately, I sent specimens to several entomologists in this country and Europe; also sent photographs to some of my friends. I had at the time a full description of the gall and fly written, but while holding it to send with other matter for publication a brief notice of a similar gall found in the West appeared in the first volume of the " American Entomologist." Dr. Walsh, who wrote the paper, did not describe the species fully, but said that it was found on the Burr oak, and that it differed in several particulars from C. globulus Harris. His brief description led me to think that his and mine might be identical, even though they grew on different species of oak, and I determined to withhold mine till I could settle the question. The death of Dr. Walsh not very long after, and later still the destruction of his collections in the great Chicago fire, has made the settlement of the question difficult, if not impossible. If at any time their identity is established his published name has priority, and I yield to the rule in such cases most cheerfully.

It is a suggestive, and certainly not a merely fortuitous fact, that those Gall-flies which inhabit promiscuously several species of Oak, confine themselves to one or the other Section or Subgenus: eg Cynips q. globulus Fitch, occurs on Q. alba and Q. montana, and also, unless I have been deceived by the similarity of the gall, on Q. macrocarpa, all three of them belonging to the first section or subgenus.

Disholcaspis mamma

Rough Bullet Gall Gall Wasp (Disholcaspis mamma Cresson) Swamp White Oak (Quercus bicolor Willd.) These round, nipple-tipped galls are found on several species of oaks. They are colored green and red when young, velvety to touch, later becoming red or dark brown. In winter the galls are very hard and may be cut with difficulty. Rough Bullet Galls are generally found on young shoots of oak.

Holcaspis mamma (Walsh)

Cynips q mamma
Holcaspis mamma
Holcaspis duricoria
Cynips duricaria
Holcaspis duricaria
Diplolepis q macrocarpae
Cynips macrocarpae
Andricus macrocarpae

Gall. (Plate VIII, Fig. 1.) In numbers or in clusters among the twigs of swamp white oak (Quercus platanoides [bicolor]) and bur oak (Quercus macrocarpa). Rounded, hard, and woody when old, brown or dark red, with a more or less distinct point at the apex. When fresh it is bright red, sometimes greenish, soft and pithy. Internally there is a free larval cell, similar to that of Holcaspis globulus. Diameter 6 to 18 mm.

Habitat. Canada to Texas.

I have united Holcaspis duricoria Bassett, with H. mamma Walsh. The description of the gall of the latter tallies exactly with that of the former, while the brief characters of the adult of H. mamma agrees with those of H. duricoria. Walsh compared his H. mamma with H. globulus and his diagnosis agrees essentially with the material of these species before me. A specimen of H. mamma was given to me by the late Dr. Ashmead, and I cannot separate it from duricoria. Bassett also suspected that H. duricoria was probably identical with H. mamma, and his species had long borne the name as a manuscript designation before the description was published. The gall of mamma is sometimes found in countless numbers on a single tree.

The types of the adults and galls of duricoria are in the American Museum of Natural History and the American Entomological Society. The types of H. mamma were lost in the great Chicago fire.