Two new oak gall wasp species (Hymenoptera: Cynipidae, Cynipini) from Quercus pontica (Fagaceae) in Turkey

Two new species of oak gall wasp, Andricus mammadovi Azmaz & Katılmış sp. n. sexual generation and Cynips fatihi Azmaz & Katılmış sp. n. asexual generation (Cynipidae: Cynipini) are described from the eastern Black Sea region in Turkey. These species induce galls on Quercus pontica K.Koch representing the first record of cynipids associated with the natural Q. pontica population in Turkey. SEM images, photos of the host galls, and data on the diagnosis, distribution, and biology of both new species are provided.

A new genus of Nearctic oak gall wasp, Grahamstoneia Melika & Nicholls, gen. nov. (Hymenoptera: Cynipidae, Cynipini)

A new genus, Grahamstoneia Melika & Nicholls, gen. nov., with one new species, G. humboldti Melika & Nicholls, sp. nov., asexual generation, is described. This new taxon occurs in the south-western Nearctic, inducing galls on two species within Quercus section Protobalanus (Q. vacciniifolia Kellogg and Q. chrysolepis Liebm.), an ecology and distribution shared with the closely related genus Heteroecus Kinsey. Descriptions, diagnoses, biology, and host associations for the new genus and species are given. The new taxon is supported by morphological and molecular data.

The Heterogonic Life Cycles of Oak Gall Wasps Need to Be Closed: A Lesson From Two Species of Dryophanta (Hymenoptera: Cynipidae: Cynipini)

In heterogonic gall wasps, the gall structure, phenology, and adult morphology differ between the asexual and sexual generations, even within the same species. Dryophanta japonica Ashmead and Dryophanta mitsukurii Ashmead were described in 1904, but their heterogonic life cycles were uncertain. To match their asexual and sexual generations, we compared the type specimens of both species with specimens of gall wasps reared to demonstrate heterogonic life cycles. This revealed that these two species are the respective asexual and sexual generations of a single heterogonic species. Based on the morphological characteristics, we transferred D. japonica to Cerroneuroterus Melika and Pujade-Villar as Cerroneuroterus japonicus (Ashmead, 1904) comb. nov. and treated the sexual generation as a junior synonym: Dryophanta mitsukurii Ashmead, 1904 syn. nov. Moreover, we examined the type specimens of other species previously suggested to be synonymous with D. mitsukurii. This showed that Neuroterus vonkuenburgi Dettmer, 1934 syn. nov. (and N. vonkuenburgi wakayamensis Monzen, 1954 syn. nov.) is the asexual generation of C. japonicus and that Neuroterus bonihenrici Dettmer, 1934 syn. nov. is the sexual generation. Judging from the original descriptions, Andricus asakawae Shinji, 1943 syn. nov., Andricus kanagawae Shinji, 1943 syn. nov., Andricus asakawae Shinji, 1944 syn. nov., Andricus kanagawae Shinji, 1944 syn. nov., and Neoneuroterus kashiyamai Monzen, 1954 syn. nov. were also regarded as the sexual generation of C. japonicus. Finally, we discussed how matching asexual and sexual generations in heterogonic gall wasps not only avoids taxonomic confusion but also contributes to progress in gall wasp biology.

Rediscovery of Cerroneuroterus apenninus (Trotter, 1923) (Hymenoptera: Cynipidae: Cynipini) a valid species from Italy with description and neotype designation

Neuroterus apenninus Trotter, 1923 associated with a Cerris section oak, Quercus cerris L., was rediscovered in Italy in 2017. Alessandro Trotter (1903) described a leaf gall collected on Q. cerris from the Italian Apennines; he did not obtain the gall inductor and ascribed the galls to the genus Neuroterus, based on morphological similarity with other Neuroterus galls. We have found the same gall and obtained the gall inducer. Detailed study of morphological characters of adults revealed that the species belongs to the genus Cerroneuroterus Melika & Pujade-Villar, 2010. The asexual generation of Cerroneuroterus apenninus comb. n. is described for the first time, a neotype is designated, and a diagnosis, host associations and biological notes are given; an identification key to the Western Palaearctic Cerroneuroterus species is provided.

A new species of Cerroneuroterus Melika & Pujade-Villar from the Eastern Palaearctic (Hymenoptera, Cynipidae, Cynipini)

A new gall wasp species, Cerroneuroterus yukawamasudai Pujade-Villar & Melika sp. nov., is described from China. The asexual generation induces leaf lenticular galls, and the sexual generation induces catkin galls on Q. acutissima and Q. variabilis. Sexual females and males are not described yet. Data on the diagnosis, distribution, and biology of the new species are provided, including a key to sexual and asexual females of all described Cerroneuroterus species. Previous misidentifications of host galls recorded in Japan are commented on. Molecular analyses were performed to assess the validity of the genus Cerroneuroterus and the affiliation of the new species.

Arthropod Community Associated With the Asexual Generation of Bassettia pallida (Hymenoptera: Cynipidae)

Cynipid gall wasps play an important role in structuring oak arthropod communities. Wasps in the Cynipini tribe typically lay their eggs in oaks (Quercus L.), and induce the formation of a ‘gall’, which is a tumor-like growth of plant material that surrounds the developing wasp. As the wasp develops, the cynipid and its gall are attacked by a diverse community of natural enemies, including parasitoids, hyperparasitoids, and inquilines. Determining what structures these species-rich natural enemy communities across cynipid gall wasp species is a major question in gall wasp biology. Additionally, gall wasps are ecosystem engineers, as the abandoned gall is used by other invertebrates. The gall-associated insect communities residing on live oaks (Quercus geminata Small and Quercus virginiana Mill.) are emerging as a model system for answering ecological and evolutionary questions ranging from community ecology to the evolution of new species. Documenting the arthropods associated with cynipids in this system will expand our understanding of the mechanisms influencing eco-evolutionary processes, record underexplored axes of biodiversity, and facilitate future work. Here, we present the community of natural enemies and other associates of the asexual generation of the crypt gall wasp, Bassettia pallida Ashmead. We compare the composition of this community to communities recently documented from two other cynipid gall wasps specializing on live oaks along the U.S. Gulf coast, Disholcaspis quercusvirens Ashmead and Belonocnema treatae Mayr. B. pallida and their galls support a diverse arthropod community, including over 25 parasitoids, inquilines, and other associated arthropods spanning 5 orders and 16 families.

Invertebrate Community Associated with the Asexual Generation of Bassettia pallida Ashmead (Hymenoptera: Cynipidae)

Cynipid gall wasps play an important role in structuring oak invertebrate communities. Wasps in the Cynipini tribe typically lay their eggs in oaks (Quercus L.), and induce the formation of a “gall”, which is a tumor-like growth of plant material that surrounds the developing wasp. As the wasp develops, the cynipid and its gall are attacked by a diverse community of natural enemies, including parasitoids, hyperparasitoids, and inquilines. Determining what structures these species-rich natural enemy communities across cynipid gall wasp species is a major question in gall wasp biology. Additionally, gall wasps are ecosystem engineers, as the abandoned gall is used by other invertebrates. The gall-associated insect communities residing on live oaks (Quercus geminata Small and Q. virginiana Mill.) are emerging as a model system for answering ecological and evolutionary questions ranging from community ecology to the evolution of new species. Documenting the invertebrates associated with cynipids in this system will expand our understanding of the mechanisms influencing eco-evolutionary processes, record underexplored axes of biodiversity, and facilitate future work. Here, we present the community of natural enemies and other associates of the asexual generation of the crypt gall wasp, Bassettia pallida Ashmead. We compare the composition of this community to communities recently documented from two other cynipid gall wasps specializing on live oaks along the U.S. Gulf coast, Disholcaspis quercusvirens Ashmead and Belonocnema treatae Mayr. B. pallida and their crypts support a diverse arthropod community, including over 25 parasitoids, inquilines, and other associated invertebrates spanning 5 orders and 16 families.

Heterogony in Cycloneuroterus (Hymenoptera: Cynipidae: Cynipini) From Rearing Experiments and DNA Barcoding

Heterogony was confirmed in the cynipid genus Cycloneuroterus Melika and Tang in rearing experiments with DNA barcoding. These experiments involved Cycloneuroterus gilvus Tang and Melika, which was previously only described from the sexual generation adult. The first rearing experiment was conducted using unidentified asexual generation females collected from Quercus gilva Blume, and gall formation by the sexual generation offspring was confirmed on folded or unfolded young leaves of Q. gilva. The second experiment was conducted using sexual generation males and females reared from the leaf galls collected from Q. gilva, and gall formation by the asexual generation offspring was observed on leaves of Q. gilva. Based on the morphological features of the sexual generation adults and galls, this species was identified as C. gilvus. The species identity of wasp specimens of sexual and asexual generations used in the rearing experiments was cross-checked using DNA barcoding with the partial sequences of the cytochrome c oxidase subunit I (COI) region (658 bp). The asexual generation adult and gall of C. gilvus are described based on these results. The importance of ‘closing the life cycle,’ in this case a demonstration of heterogony, in oak gall wasps (Cynipini) is discussed.

New species of Dryocosmus Giraud gallwasps from California (Hymenoptera: Cynipidae: Cynipini) galling Chrysolepis Hjelmq. (Fagaceae)

Four species of Dryocosmus cynipid gallwasps are now known to induce galls on Chrysolepis in California and Oregon. Two new species, Dryocosmus demartinii Melika, Nicholls & Stone and Dryocosmus juliae Melika, Nicholls & Stone are described. Males of the sexual generation of D. rileypokei plus adults of the asexual generation of this species are both described for the first time. A detailed description of D. castanopsidis is given for the first time. In addition to descriptions we provide diagnoses and information on biology and host associations for all four species. All the newly described taxa are supported by morphological and molecular data.

The oak gall wasps of Israel (Hymenoptera, Cynipidae, Cynipini)—diversity, distribution and life history

Oak-galling wasps (Hymenoptera: Cynipidae, Cynipini) have been studied in Israel only superficially so far, despite interest in the Israeli fauna given its location at the southern edge of distribution range of the wasps and their oak hosts. We provide the first comprehensive review of the Israeli fauna of oak cynipids based on an extensive survey of the five naturally occurring oak species in Israel. We report 53 cynipid species, 37 of which are reported from Israel for the first time, 10 are currently known only from this country, and 9 are undescribed. With 27 species, Andricus is by far the biggest genus in Israel, followed by Cerroneuroterus, Neuroterus Plagiotrochus, and Pseudoneuroterus with 4 species each. Andricus megalucidus is synonymized under A. cecconii and Cerroneuroterus cerrifloralis is synonymized under C. lanuginosus. The sexual generations of Andricus cecconii, A. coriariformis, A. coriarius, A. miriami, Cerroneuroterus lanuginosus and Pseudoneuroterus macropterus are reported here for the first time. We recorded 65 gall types, with bud galls being the most common and conspicuous, followed by leaf and catkin galls. We provide illustrated keys for all Israeli species based on their galls, as well as information on host associations, life history, phenology and distribution patterns where available. 21 cynipid species are associated with Quercus ithaburensis and 27 species are associated with Q. boissieri, whereas Q. libani, Q. calliprinos and Q. cerris host much fewer species. Most species are currently known from either their sexual or asexual generation while only 24% of them are known from both. Mount Hermon was found to be an important hotspot, hosting about half of the Israeli cynipid fauna, and species richness generally declines from the Golan Heights southwards to the Judean Mountains. Cynipid species that are associated with oaks of sections Cerris and Quercus in Europe are mostly associated with the same sections in Israel.