Amphibolips quercusspongifica (agamic)

Amphibolips confluenta (sexgen)

Amphibolips globulus

Amphibolips quercusinanis (sexgen)

Amphibolips spinosa (agamic)

Amphibolips quercuscitriformis (agamic)

Amphibolips acuminata

Amphibolips ilicifoliae (sexgen)

Amphibolips quercuscoelebs (sexgen)

Amphibolips melanocera (sexgen)

Amphibolips quercuscinerea (sexgen)

Amphibolips cookii (agamic)

Amphibolips tinctoriae

Amphibolips nubilipennis (sexgen)

Amphibolips quercusracemaria (sexgen)

Amphibolips quercusjuglans (agamic)

Amphibolips gainesi

Amphibolips quercusfuliginosa (agamic)

Amphibolips trizonata (sexgen)

Amphibolips palmeri

Amphibolips confluens form spongifica

Cynips confluens
Cynips quercus coccinea
Amphibolips cocciniae
Amphibolips coccinea
Cynips quercus spongifica
Cynips spongifica
Amphibolips spongifica

Gall. On the leaves usually from a vein or the petiole on red oak (Quercus rubra), scarlet oak (Quercus coccinea), quercitron or yellow oak (Quercus velutina) in May and June. Globular or nearly so, smooth, shining or opaque with a thin outer shell. Internally filled with a juicy white spongy substance and with a large, hard, central larval cell. When fresh the gall is green, and light brown when old and dry, with the internal spongy substance dark brown. Diameter, 25 to 50 mm.

Habitat: Canada; New England and Middle States, south to GA and west to CO.

This well-known gall is very common and hundreds may often be found upon a single tree. It makes its appearance early in may, as soon as the leaves put forth, on different kinds of oaks belonging to the red oak group, and is fully grown in a few weeks. It is popularly known as "oak-apple" or May-apple, owing to its superficial resemblance to a small apple. From a certain number of the galls emerge, by the middle of Jun, both male and female gall flies. The gall-flies which emerge in October or the following spring are all agamous females.

[Beutenmuller's drawings are the ones reprinted in Felt as "A confluens"]

Amphibolips caroliniensis

Gall. Attached to the midrib near the base of a leaf and prevents its development beyond the point of attachment. It occurs on a species of oak probably, Quercus minor [stellata--this is likely erroneous and perhaps should be marilandica]. Resembles the galls of Amphibolips spongifica and Amphibolips cinerea, but the surface is more coarsely reticulated and less glossy. Internally the spongy mass surrounding the larval cell is of a much darker color. The outer shell is thinner and in dried specimens is irregularly shrunken and depresssed. 

Habitat: NC

Amphibolips longicornis

Gall. Allied to A spongifica, and probably found in similar situations on the leaves and young twigs of oak. Monothalamous and very thin shelled. Internally it is of a soft, light and spongy consistency not unlike that of A spongifica. Length 35 mm. Width 30 mm.

Habitat: TX

Amphibolips confluens

Cynips confluens
Cynips aciculata
Cynips quercus aciculata
Amphibolips aciculata
Andricus confluens
Amphibolips confluens
Amphibolips confluentus
Amphibolips confluentis

[Beutenmueller gives no description of A confluenta itself, only the form spongifica, which he treats as the same species:]

Gall. On the leaves usually from a vein or the petiole on red oak (Quercus rubra), scarlet oak (Quercus coccinea), quercitron or yellow oak (Quercus velutina) in May and June. Globular or nearly so, smooth, shining or opaque with a thin outer shell. Internally filled with a juicy white spongy substance and with a large, hard, central larval cell. When fresh the gall is green, and light brown when old and dry, with the internal spongy substance dark brown. Diameter, 25 to 50 mm.

Habitat: Canada; New England and Middle States, south to GA and west to CO.

This well-known gall is very common and hundreds may often be found upon a single tree. It makes its appearance early in may, as soon as the leaves put forth, on different kinds of oaks belonging to the red oak group, and is fully grown in a few weeks. It is popularly known as "oak-apple" or May-apple, owing to its superficial resemblance to a small apple. From a certain number of the galls emerge, by the middle of Jun, both male and female gall flies. The gall-flies which emerge in October or the following spring are all agamous females.

Amphibolips globulus sp. nov.

Gall. On the twigs of black jack oak (Quercus marylandica [marilandica]) in September. Globular, thick-shelled, with a small nipple at the apex. Filled with a very dense mass of radiating spongy substance. Green when fresh, brown when dry. Diameter 14 to 17 mm. 

The gall very much resembles that of Holcaspis globulus [Disholcaspis quercusglobulus] externally, but the internal structure is very different. 

Habitat: NJ

Amphibolips inanis (Osten Sacken)

Callaspidia confluenta
Cynips quercus inanis
Cynips inanis
Amphibolips inanis

Gall. On the leaves of scarlet and red oak (Quercus coccinea and Quercus rubra) in May and June. Bright green, sometimes with darker spots. Globular or nearly so, sometimes with a small nipple at the apex, thin shelled, with the surface glossy. Inside with a larval cell held in position by thread-like white filaments. When dry the gall becomes yellowish brown, often with darker brown patches. It is then very thin shelled and brittle. Diameter 25 to 35 mm.

Externally the gall may be mistaken for that of Amphibolips confluens, but it is as a rule smaller and the larval cell is held in position by radiating fibers while the galls of confluens are filled completely with a dense spongy substance. The adults emerge in June and early in July.

Habitat: Canada; New England and Middle States; MD, VA, NC, OH, MI, IN, IO

Amphibolips spinosa

Gall. On leaves of laurel oak (Quercus laurifolia). Brown, globular, covered with prickles or spines. The outer shell is thick and internally it is composed of a slight spongy substance, which surrounds the thin central larval cell. Diameter 7.50 mm.

Habitat: Florida.




Amphibolips citriformis

Cynips quercus citriformis

Gall. On the twigs of willow oak (Quercus phellos). Varying considerably in shape from narrow spindle shaped to globular, with the apex attenuated to a sharp point. Smooth, shining, yellowish, and rather thin shelled. Internally is a larval cell held in position by a few thin, radiating filaments. Length 12 to 24 mm; width 6 to 12 mm.

Habitat: FL

Amphibolips acuminata Ashmead

Gall. Attached to the twigs of black jack oak (Quercus marylandica) in May and June. Elongated, subglobular, sometimes pepper-shaped, with the apex drawn out into a point, which is sometimes bent. Yellowish brown, probably green when fresh, thin shelled as in Amphibolips confluens and smooth. Internally it is filled with a spongy substance, with a central, hard, larval cell. Length, 30 to 55 mm. Diameter 15 to 30 mm.

Habitat: MD, VA

Amphibolips ilicifoliae

Cynips quercus ilicifoliae
Cynips ilicifoliae

Gall. On the upper side of the leaves of scrub oak (Quercus nana [ilicifolia]), standing erect or nearly so, sometimes entirely preventing the development of the leaf and apparently growing out of the petiole. Dark green, elongated, fusiform with the apex rather longer and more slender than the basal portion, and often curved. The outer shell is thin, smooth, and opaque. Internally with a larval cell held in position by radiating fibers as in Amphibolips inanis. Length 25 to 55 mm; width 7 to 20 mm.

Habitat: CT, NY, NJ, PA, DE, MD

Galls may be found in May and June and the adults emerge during the latter month.

Amphibolips coelebs

Cynips quercus coelebs
Cynips coelebs

Gall On the edge of a leaf of scarlet oak (Quercus cocinea) and red oak (Quercus rubra). Sometimes also found on young and tender twigs. Elongated or fusiform, narrow, with the apex prolonged into a point; base usually with a long pedicel, inserted on the edge of the leaf and being the prolongation of the leaf-vein. Pale green with a thin outer shell. Internally there is an oblong thin larval cell, held in position by radiating fibers. Length 20 to 25 mm; width 4 to 8 mm.

The gall makes its appearance from about the middle of May to early in June, and the adult emerges during the latter month.

Habitat: NY, NJ, DC

Amphibolips melanocera

Gall Issuing from the bud axilis of water oak (Quercus nigra). Globular or elongate oval, sometimes with a very short nipple at the apex. Greenish brown and yellowish green when fresh. Coffee brown and very glossy when dry. The outer shell is very thin, and internally there is a central kernel held in place by some very thin hair-like filaments. When dry the gall is very brittle, and may be easily crushed with the fingers. Diameter 7-15 mm.

The gall is constructed on the same plan [as Amphibolips citriformis] but is rounded or elongate oval and without a long pointed terminal prolongation at the apex.

Habitat: FL

Amphibolips cinerea

Cynips quercus cinerea

Gall. Attached to the twigs and limbs of blue-jack or upland willow oak (Quercus brevifolia [incana]). Large, spherical or elongate oval, with a small nipple at the apex and of a dark crimson, mottled with small spots of a lighter color. The outer shell is rather thick, and when old it is brown, hard and brittle. Internally there is a central larval cell held in position by very dense brownish spongy filaments. Length 24 to 35 mm; width 20 to 30 mm.

Habitat: FL

Amphibolips cooki

Amphibolips cookii

Gall. Issuing from a bud on the terminal twigs of red oak (Quercus rubra) in September and October. Almost globular and usually with a small nipple at the apex. Green and succulent and spotted with red when fresh, and with the outer shell moderately thick. Internally with a central larval cell held in position by radiating fibers. When old the gall becomes brown and shriveled in appearance. Diameter about 16 to 18 mm.

The gall somewhat resembles that of A inanis, but differs by being smaller, a thicker outer shell and much stouter radiating fibers. It is an autumnal species and the galls readily break off when touched, or it falls with the leaves or before them. It is a bud gall, while that of A inanis occurs on the leaves in spring. The adult emerges late in August and early in September. 

Habitat: CT, NJ, NY, NC, PA, MI, IO

Amphibolips tinctoriae

Gall. Issuing from a bud on quercitron or yellow oak (Quercus velutina) and red oak (Quercus rubra) in autumn. Almond-shaped, acuminate, at tip, compressed with the opposite sides keeled. Green or red when fresh and brown when old. Rather thick shelled and smooth. Internally it is hollow with a central larval cell held in position by radiating fibers. Length 12 to 20 mm. 

The gall is a deformation of a bud and the characteristic keel shaped sides and compressed form, separates it at once from all other known galls of Amphibolips.

Habitat: CT, NJ, PA

Amphibolips nubilipennis

Cynips nubilipennis
Callaspidea nubilipennis
Cynips quercus sculptus
Cynips quercus sculpta
Amphibolips sculpta

Gall. Attached to the under side of leaves of red oak (Quercus rubra) and scarlet oak (Quercus coccinea). Globular or oblong oval and the color of a green grape sometimes with a tinge of pink, succulent and translucent. Internally there is a single cell which can be seen when held up to the sunlight. Diameter 6 to 18 mm.

The galls of this distinct species may be found fully developed from about the middle of June to early in July, the fly appearing during the latter month.

The gall when fresh is almost exactly like a green grape and is sometimes partly or wholly pinkish. It is juicy and soft with a hard central larval cell. 

When dry the gall is shriveled, and very distorted in shape. It is then hard and woody and contains a rounded larval cell in surrounding substance. 

Habitat: NY, NJ, CT, MA, PA, MI, IO, IN, IL

Amphibolips racemaria

Cynips quercus racemaria

Gall. On the under side of leaf of laurel oak (Quercus laurifolia) in April and May. Globular or spherical, crisp, sour and succulent. Green when fresh, and brown and shriveled when dry. Internall with a reddish larval cell. Diameter 8 to 10 mm. 

The gall very much resembles that of Amphibolips nubilipennis.

Habitat: FL

Amphibolips prunus

Cynips quercus juglans
Cynips juglans
Cynips quercus prunus

Gall. On acorn cups of red oak (Quercus rubra), scrub oak (Quercus nana [ilicifolia]), quercitron oak (Quercus velutina) and scarlet oak (Quercus cocinea) in August and September. Bright red, more or less globular, smooth, and sometimes looking almost like a marble. When fresh it is solid but fleshy and of a pink color inside, shading into yellow toward the middle, where there is a single large larval chamber. Subsequently it becomes mature and it turns blood red, and when old and dry it becomes so hard as to be cut with difficulty. Diameter 15 to 25 mm.

Habitat: New England and Middle States, south to GA, and west to CO.

Amphibolips gainesi

Gall. Attached by a small point to the side of an acorn cup of black jack oak (Quercus marilandica). Perfectly round and smooth and of a dense corky substance. Internally it is rusty brown, contains a large central larval chamber, which is firmly imbedded in, and adherent to the surrounding mass. Diameter 24 to 42 mm.

The gall is considerably larger than that of A prunus [quercusjuglans] and does not shrivel up like prunus.

Habitat: TX

Amphibolips fuliginosa

Cynips quercus fuliginosa

Gall. On the twigs or possibly on the acorns of willow oak (Quercus laurifolia) in August. Rounded or spherical, smooth, and of a corky texture, with a central larval cell. Reddish brown and rather hard when dry. Diameter 8 to 12 mm.

The gall has the appearance of a miniature gall of Amphibolips prunus [quercusjuglans] and is similar in structure. WH Ashmead states that the galls drop from large trees in August and that he was unable to find out whether they grow on the twigs or leaves. I am of the opinion that it is an acorn gall owing to the resemblance of the adult and structure of the gall to that of A prunus.

Habitat: GA, FL

Amphibolips trizonata

Gall. On the young twigs of a species of oak in June. Almost or entirely globular with a moderately thick outer shell. Yellowish and almost smooth. Internally it is completely filled with a soft, pithy substance like Amphibolips palmeri. Centrally there is a larval cell which is fastened to the surrounding mass. Diameter 20 to 35 mm.

According to WH Ashmead, the gall is said to grow on the blossoms of an oak.

Habitat: AZ

Amphibolips palmeri

Gall. On the terminal small twigs of a species of oak (Quercus sp). Monothalamous, round, with the surface uneven, or somewhat wrinkly, sometimes with a few scattered very short projections. Light yellowish brown; the outer shell is thin, but firm. Internally it is of a soft, uniform porous or spongy consistency, filling the entire gall. The larval cell is rounded and is embedded in the soft internal substance. Diameter 35 to 70 mm.

Habitat: Summit of Sierra Madre, Chihuahua and Guadalajara, Jalisco, Mexico

The largest known species of gall-fly and "oak apple gall." 

The species of Amphibolips and their galls