Fires are ubiquitous features of many terrestrial ecosystems and can greatly impact the structure and evolution of plant communities. However, much less is known about how fire history impacts higher ...trophic levels. Using detailed records on the history and intensity of fires at the Archbold Biological Station (ABS) in central Florida, USA, we examined how time-since-fire affects the cynipid gall wasp assemblage (Hymenoptera: Cynipidae) associated with four oak species (
Quercus
) that are dominant components of the plant community in this region. Cynipid abundance, richness and diversity were quantified from 1249 oak trees/shrubs in 20 sites that varied in time-since-fire from 1.5 to 91 years. Among all sites and oaks, we found 24 species of cynipids and there was very little species overlap among oak species, even within the same site. Gall abundance increased with time-since-fire and was correlated with tree height, suggesting that available host material or plant architecture may be a primary driver of cynipid recovery. Within 3 years of a fire, 14 of the 23 cynipid species were detected among the sites, and by seven years since fire, all but two species could be detected. Overall, species richness and diversity reached an asymptote within ≈ 7 years. Given how quickly the cynipid assemblage recovers after a fire, frequent fires at ABS are unlikely to negatively impact these insects. However, in smaller or more isolated scrub-oak fragments, recovery could be much slower.
Sweet Tetra-Trophic Interactions Nicholls, James A.; Melika, George; Stone, Graham N.
The American naturalist,
01/2017, Letnik:
189, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Many herbivores employ reward-based mutualisms with ants to gain protection from natural enemies. We examine the evolutionary dynamics of a tetra-trophic interaction in which gall wasp herbivores ...induce their host oaks to produce nectar-secreting galls, which attract ants that provide protection from parasitoids. We show that, consistent with other gall defensive traits, nectar secretion has evolved repeatedly across the oak gall wasp tribe and also within a single genus (Disholcaspis) that includes many nectar-inducing species. Once evolved, nectar secretion is never lost in Disholcaspis, consistent with high defensive value of this trait. We also show that evolution of nectar secretion is correlated with a transition from solitary to aggregated oviposition, resulting in clustered nectar-secreting galls, which produce a resource that ants can more easily monopolize. Such clustering is commonly seen in ant guard mutualisms. We suggest that correlated evolution between maternal oviposition and larval nectar induction traits has enhanced the effectiveness of this gall defense strategy.
Native to China, the Asian chestnut gall wasp,
Dryocosmus kuriphilus
(ACGW), was first found outside its native range in Japan and the Korean peninsula in the mid-twentieth century. After appearing ...in North America in 1974, it was found in Europe a few decades later. Since then, the gall wasp has spread throughout the distribution of chestnut in Europe. The ACGW’s discovery in North America and Europe elicited numerous studies to understand its invasive potential in these areas and how to control its spread and impact on chestnut production. Although endemic parasitoids responded positively to
D. kuriphilus
with low parasitism rates, the most effective management tactic has been classical biological control via the introduction of the parasitoid
Torymus sinensis
from its native range in China. This review summarizes the history of introduction, spread, and current distribution of
D. kuriphilus
, and highlights one of the most successful cases of classical biological control against a forest pest.
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 Asian chestnut gall wasp (ACGW), Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae), is a global pest of chestnut trees. This pest was first recorded in Slovenia in 2005. Despite strict ...phytosanitary measures it was present throughout the country in native chestnut stands by 2013. We provide here the first overview of the parasitoids of ACGW in Slovenia recorded over a 4-year period and the direct interactions between parasitoid communities attacking hosts on chestnut and oaks at the same sites. A total of 27 species of native parasitoids that normally parasitize oak cynipids emerged from ACGW galls. The most abundant species were Torymus flavipes and Eupelmus urozonus. Seven species appear to be geographically well distributed in Slovenia. Twelve species of oak gall wasp were parasitized by 19 species of parasitoids. All native parasitoids have broad host ranges, so a large parasitoid diversity within this community can be expected. This is a novel study comparing the parasitoid communities associated with chestnut and oak galls.
Since the rapid spread of the Asian chestnut gall wasp (ACGW) throughout south-east Europe in the last few years, the possibilities of its control have been increasingly investigated. Due to ...constraints in available suppression measures in forest stands, biological control is recognized as the most suitable action to lower the abundance of the new invasive pest.
Torymus sinensis
, as a specialized parasitoid chalcid wasp of ACGW, was introduced to suppress the pest in Italy in 2005, and later in Croatia, Hungary (2014) and Slovenia (2015). We investigated the native parasitoid complex associated with ACGW in Slovenia, Croatia and Hungary over 8 years of sampling. We found 41 species of native parasitoids, eight of which are the first records on ACGW in Europe, adding up to a total of 51 species known to parasitize ACGW. These findings represent a large complex of cynipid-parasitoid fauna. Moreover, the abundance of native parasitoid populations on ACGW have demonstrated a temporal surge between the invasion of a new alien host (ACGW) and the onset of its specialized parasitoid,
T. sinensis
. Our results indicate that the introduced parasitoid acts as a very successful biocontrol of ACGW, outcompeting native parasitoids. This outcome should be considered as beneficial through the maintenance of ecological balance in affected forest ecosystems.
Cynipid gallwasps comprise 1364 species worldwide, predominantly in temperate regions of the Holarctic. The vast majority of recorded species are from the Nearctic and the Western Palaearctic, both ...of which are long-standing centers of research on the taxonomy and biology of this group. In contrast, the Eastern Palaearctic and the Oriental Region faunas are much less studied, but potentially extremely rich. Previously recorded species richness of cynipid groups in the Eastern Palaearctic and Oriental regions probably represents a significant underestimate. This is particularly marked for gallwasps associated with oaks (tribe Cynipini), as has been shown by recent works, which describe many new species galling oaks in the subgenera Quercus and Cyclobalanopsis and plants of the other Fagaceae genera (Castanopsis, Lithocarpus and Castanea). In the present paper, we summarise the current knowledge of oak gallwasps in the regions that extend from Pakistan, through Nepal and China to Japan and south to Indonesia, and list a total of 97 species of Cynipini from the area.
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.
The sexual generation of Dryocosmus destefanii Cerasa Melika, 2018 that emerges from galls on Q. suber L. in Italy is described for the first time, establishing its heterogonic life cycle. We provide ...observations on its distribution, illustration of adults and galls and information on its biology as supported by morphological and molecular data. An illustrated identification key to Western Palaearctic Dryocosmus species is also given.
After the examination of the oak cynipid inquilines deposited in the Parasitic Hymenoptera Collection of the Agriculture and Forestry University of Zhejiang (ZAFU, China), we provide a revision of ...the species of Saphonecrus, Lithosaphonecrus, Ufo (Hymenoptera: Cynipidae: Synergini) and Ceroptres (Hymenoptera: Cynipidae: Ceroptresini) found in mainland China. Two new species of Saphonecrus are described: S. albidus Lobato-Vila and Pujade-Villar, sp. nov. and S. segmentatus Lobato-Vila and Pujade-Villar, sp. nov. Four Saphonecrus species (S. gilvus Melika and Schwéger, 2015, S. globosus Schwéger and Tang, 2015, S. leleyi Melika and Schwéger, 2015, and S. nantoui Tang, Schwéger and Melika, 2015) are new records for this region. We also provide new data on the biology and distribution, redescriptions, illustrations and corrections to some of the species, as well as updated keys to Eastern Palaearctic and Oriental species of Saphonecrus and Ufo. Three species of Saphonecrus are considered to have an uncertain status: S. gemmariae (Ashmead, 1885) incertae sedis from the USA, S. excisus (Kieffer, 1904) nomen dubium from India, and S. sinicus Belizin, 1968 incertae sedis from China. The validity of Saphonecrus in the Nearctic region as well as the current status of S. serratus Weld, 1926 from the Philippines and S. favanus Weld, 1944 from the USA are discussed.
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