Gall wasps, also traditionally calledgallflies, are hymenopterans of the family Cynipidae in the wasp superfamily Cynipoidea. Their common name comes from the galls they induce on plants for larval development. About 1,300 species of this generally very small creature are known worldwide, with about 360 species of 36 different genera in Europe and some 800 species in North America.
Neuroterus is a genus of gall wasps that induce galls on oaks in which the wasp larvae live and feed. Some species produce galls that fall off the host plant and 'jump' along the ground due to the movement of the larvae within.
Andricus is a genus of oak gall wasps in the family Cynipidae.
Cynipini is a tribe of gall wasps. These insects induce galls in plants of the beech and oak family, Fagaceae. They are known commonly as the oak gall wasps. It is the largest cynipid tribe, with about 936 to 1000 recognized species, most of which are associated with oaks. The tribe is mainly native to the Holarctic.
Andricus quercuscalifornicus, or the California gall wasp, is a small wasp species that induces oak apple galls on white oaks, primarily the valley oak but also other species such as Quercus berberidifolia. The California gall wasp is considered an ecosystem engineer, capable of manipulating the growth of galls for their own development. It is found from Washington, Oregon, and California to northern regions of Mexico. Often multiple wasps in different life stages occupy the same gall. The induced galls help establish complex insect communities, promoting the diversification in niche differentiation. Furthermore, the adaptive value of these galls could be attributed their ecological benefits such as nutrition, provision of microenvironment, and enemy avoidance.
Feron kingi, the red cone gall wasp, is a species of gall wasp in the family Cynipidae.
Striatoandricus is a genus of Neotropical gall wasps (Cynipidae). There are six described species, four of which were formerly included in Andricus. All species induce galls on oaks in which their larvae live and feed.
Druon fullawayi, also known as the yellow wig gall wasp, is a species of gall wasp in the family Cynipidae. It was previously placed in the genus Andricus. William Beutenmüller described the female adult wasps as 1.5-2.25 mm long, black with brown mouth parts and brown legs. The galls of D. fullawayi are tan or yellow, woolly, and measure 5-8 mm in diameter. Each gall holds a single chamber for larvae. They are found in California on oak trees, especially Quercus lobata.
Feron crystallinum, also known as the crystalline gall wasp, is a species of gall-forming wasp in the genus Feron. The galls of its all-female parthenogenic generation are pink and covered in hairs that are white, red, or brown. These galls are often massed together in clumps that can cover the underside of leaves. Individual galls are 12–14 mm high, 7 mm across, and have a single chamber for larvae. This generation emerges in late winter. In the spring, the bisexual generation of males and females induces much smaller galls with shorter hairs. F. crystallinum galls are found in all species of oaks in California.
Feron gigas, also known as the saucer gall wasp, is a species of gall-forming wasp in the genus Feron. It induces galls on the leaves of scrub oaks, blue oaks, and Engelmann oaks. The galls produced by its all-female generation, which emerges in winter, are 3-4 mm wide, circular with raised edges. They are red, pink, brown, or purple. The larval chamber exists as a raised bump in the gall's center. The bisexual generation produces galls that are brown and cone-shaped.
Burnettweldia plumbella, also known as the beaked twig gall wasp, is a species of gall wasp. Previously in the genus Disholcaspis, it was moved into a new genus, Burnettweldia, in 2021. This wasp induces galls on oak trees, including blue oak, leather oak, Muller's oak, and scrub oaks. The galls are up to 15 mm in diameter and brightly colored, coming in either red with yellow spots or green with yellow spots. Their name comes from the galls' pointed tip. Galls are formed in spring and summer, and adults emerge from them in November and December. The adult wasps are 3–4 mm in length.
Feron pattersonae, also known as the plate gall wasp, is a species of oak gall wasp in the genus Feron. Their hosts are among the white oaks grouping of oaks, with blue oak being common.
Feron atrimentum, also known as the striped volcano gall wasp, is a species of gall-forming wasp in the genus Feron. It induces galls on blue oak leaves. Like other oak gall wasps, it has two generations: a bisexual generation, and a parthenogenic female generation. The bisexual generation produces round, 3–4 millimetres (0.12–0.16 in) galls in spring that start as green or pink, and then turn brown. The unisexual generation produces conical, 4–4 millimetres (0.16–0.16 in) galls in summer that are pale with red stripes.
Acraspis guadaloupensis is a relatively uncommon species of cynipid wasp that produces galls on intermediate oaks. The intermediate oak disc wasp was first described in 1911 and has been moved between genera more than once. Distribution is limited to California in North America. The flattened galls appear on leaves of Quercus chrysolepis, the canyon live oak.
Feron bakkeri, also known as the pinched leaf gall wasp, is a relatively uncommon species of gall-inducing hymenopteran. They produce pink leaf galls on Oregon oaks and scrub oaks. The distribution of this wasp is California and Oregon in North America. It was previously placed in the genus Andricus.
Trichoteras is a genus of gall-inducing Hymenopteran that has several species formerly classed as Andricus. Trichoteras characteristics include antennae with 10 flagellomeres. An entomologist writing in 2018 stated that "is questionable that Heteroecus and Trichoteras should be synonymized with Andricus" in regard to a proposed taxonomic reorganization of 2002. Ronald A. Russo in Plant Galls of the Western United States moves species like the golden oak apple wasp from Andricus to Trichoteras, while acknowledging the previously accepted binomials. William Harris Ashmead first defined this genus in 1897.
Callirhytis congregata, formerly Andricus congregata, the sausage flower gall wasp, is a species of hymenopteran that induces galls on the catkins of coast live oaks, interior live oaks, and canyon live oaks in California in North America. This wasp is considered locally common. William Harris Ashmead described Andricus congregatus as producing a gall like a "rugose, yellowish brown woody swelling, containing numerous cells growing apparently from the extreme tips of very slender twigs of Quercus chrysolepis, the gall appearing to have a long peduncle".
Besbicus maculosus, formerly Andricus maculosus and Cynips maculosa, also known as the pear gall wasp, is an uncommon species of cynipid wasp that induces galls on oak trees on the west coast of North America. The wasp oviposits on leather oak and scrub oak leaves. Fresh galls are green. This wasp has been observed in California.
Feron is a genus of oak gall wasps in the Nearctic. It was established by Alfred Kinsey in 1937, then re-established in 2023.
Andricus chrysolepidicola , also known as the irregular-spindle gall wasp, is a species of cynipid wasp that induces stem galls on blue oaks, valley oaks, scrub oaks, and leather oaks in North America. The stem galls are the first-year unisexual gall of this species; a second-year bisexual generation induces bud galls. This species is primarily known from California but may found elsewhere along the Pacific coast and inland to Nevada.
