365 research outputs found
Sweet tetra-trophic interactions: multiple evolutions of nectar secretion, a defensive extended phenotype in cynipid gallwasps
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
A new genus of oak gallwasp, Coffeikokkos Pujade-Villar & Melika, gen. n., with a description of a new species from Costa Rica (Hymenoptera, Cynipidae)
A new genus of oak gallwasp, Coffeikokkos Pujade-Villar & Melika, gen. n., is described from Costa Rica. Diagnostic characters and generic limits of the new genus are discussed in detail. The new genus includes Coffeikokkos copeyensis Pujade-Villar & Melika, sp. n. which induces galls on stems of Quercus bumelioides, an endemic oak to Costa Rica, Honduras and Panama. The new species and galls are described and illustrated
Parasitoid complex of leaf miner Pyllonorycter comparella (Lepidoptera, Gracillariidae) in Hungary
Abstract
Between 2011 and 2014, 1,154 mines of Phyllonorycter comparella (Duponchel) were collected at 12 locations in Hungary and were put into single-mine rearing containers. A total of 574 parasitoid specimens belonging to 29 parasitoid species (26 Chalcididae, 2 Encyrtidae and 1 Braconidae) emerged. Of these species, 13 have not yet been mentioned in either international or in Hungarian literature as a parasitoid of the P. comparella. The species assemblages of the parasitoid complexes varied greatly among the sample sites. The primary dominant species of the total samples was found to be Sympiesis sericeicornis (Nees), an abundant idiobiont solitary ectoparasitoid. Among the species reared, we have found specialist parasitoids such as Achrysocharoides scaposa (Erdős) and even species never recorded from Populus (Zagrammosoma variegatum (Masi)) according to the Universal Chalcidoidea Database.</jats:p
Két invázív akác-aknázómoly (Parectopa robiniella és Phyllonorycter robiniella) jelentőségének, életmódjának és természetes ellenségeinek vizsgálata = Importance, life history and natural enemies of two invading leaf miners (Parectopa robiniella and Phyllonorycter robiniella) of black locust
A Parectopa robiniella 1983., a Phyllonorycter robiniella 1996. óta van jelen a magyar faunában. Mindkét faj gyorsan terjedt el az országban, sokhelyütt már károkat is okoznak. Az utóbbi 10 év átlagában a Parectopa kártételét 3813, a Phyllonorycter-ét 837 ha-ról jelentették Ellentétben a korábbi várakozásokkal, nem igazolható az aknázott levelek korai lehullása. A Parectopa két-, a Phyllonorycter háromnemzedékes. A Parectopa aknái 2-3 héttel később, kb. június közepén jelennek meg. A Parectopa hernyó magányosan fejlődik, a Phyllonorycter aknában akár 8 lárva is található. A kifejlett Parectopa lárva az avarban, a Phyllonorycter lárvák az aknában bábozódnak. A Phyllonorycter imágóként és bábként, a Parectopa bábként telel. A hazai aknázók parazitoidjai elfogadták a két új fajt. Phyllonorycter-ből 19, Parectopa-ból 12 parazitoid fajt neveltünk. A domináns fajok területenként és évenként különbözőek, de a Pholetesor nanus és az Achysocharoides cilla fajok a legjelentősebbek. A legmagasabb parazitáltság Phyllonorycter-nél 47,6 %, a Parectopa-nál 15,3 % volt, azaz a parazitoidok jelentős szerepet játszanak a szabályzásában. A Phyllonorycter parazitáltsága mindig magasabb volt, mint a Parectopa-é. Ennek okai az eltérő életmód (nemzedékszám, bábozódás helye, stb.), illetve az, hogy amíg Magyarországon 60-nál több Phyllonorycter faj ismert, addig Parectopa (beleértve a P. robiniella-t) csak 2. Ezért a parazitoidok lassabban képesek elfogadni a Parectopa-t, mint a Phyllonorycter-t. | Parectopa robiniella was first found in Hungary in 1983, Phyllonorycter robiniella in 1996. Both spread through the country very fast, becoming abundant at many places. As average of the last 10 years, damage of Parectopa is reported from 3,813, Phyllonorycter from 4,837 ha. We could not prove the early fall of the mined leaves. Parectopa has 2, Phyllonorycter has 3 generations/year. First mines of Parectopa appear 2-3 weeks later than Phyllonorycter mines. Parectopa larvae develop singly, up to 8 larvae of Phyllonorycter can live in 1 mine. Matured Parectopa larvae pupate in the litter, Phyllonorycter larvae within the mine. Phyllonorycter overwinters as adult or pupa, Parectopa as pupa. The native parasitoids accepted the two new hosts. 19 species of parasitoids from Phyllonorycter and 12 from Parectopa were recorded. The dominant species were different in different years/places, but Pholetesor nanus and Achysocharoides cilla were the most important. The highest of parasitism was 47.6% for Phyllonorycter and 15.3% for Parectopa. So parasitoids play significant role in regulation of populations. The rates for Phyllonorycter were always higher than for Parcetopa. Possibly because of the different life history (number of generations, place of pupation, etc.) and also because while more than 60 Phyllonorycter present in Hungary, only 2 Parectopa (incl. P. robiniella). Therefore the parasitoids are probably able to accept and use Phyllonorycter more efficiently than Parectopa
Biological Control of the Invasive Dryocosmus kuriphilus (Hymenoptera: Cynipidae) - an Overview and the First Trials in Croatia
Background and Purpose: Dryocosmus kuriphilus is a globally invasive insect pest, spreading very quickly in new habitats and making serious damage to sweet chestnut forests in Croatia and in several other European countries. Indigenous parasitoid species trophically associated with oak gallwasps have adapted to this new host but cannot effectively regulate its population density. Classical biological control using parasitoid Torymus sinensis has been proven to be the only effective method of controlling the populations of D. kuriphilus and has been successfully applied in Japan, South Korea, the USA and Italy. The aim of this review paper is to provide overview and up-to date knowledge about biological control of D. kurphilus and to describe first steps of introduction of T. sinensis to sweet chestnut forests in Croatia.
Conclusions and Future Prospects: Results presented in this paper show adapted biology and behavioural traits of T. sinensis to its host D. kuriphilus. The history and results of introductions of T. sinensis to Japan, the USA, Italy, France and Hungary are shown. The first report of release of T. sinensis to sweet chestnut forests in Croatia is given with discussion on native parasitoids attacking D. kuriphilus. Possible negative effects of T. sinensis on native parasitoid fauna and risks that could influence the successful establishment of T. sinensis in Croatia are discussed. Previous experiences have shown that T. sinensis can successfully control the population density of D. kuriphilus, slowing down the spread and mitigating negative impact of this invasive chestnut pest and keeping the damage of D. kuriphilus at acceptable level. High specificity of T. sinensis suggests that it has limited potential of exploiting native hosts but further detailed monitoring of native parasitoid and possible interactions with introduced T. sinensis is strongly suggested
Contribution to the knowledge of the parasitoid fauna of leaf mining sawflies (Hymenoptera: Tenthredinidae) of forest plants in Hungary
Background and Purpose: Despite the importance of studying the native enemy complex of the introduced and invasive leaf miner sawfly species in their native territories, few studies have been done in recent years concerning the species component and the regulating potential of their parasitoid complexes (in both native and invaded area). Heterarthrus vagans and Fenusa dohrnii are only some of the species which are native in Palearctic area, but alien invasive in North America, causing damage on forest plantations. In this short paper we provide our original data to the knowledge of parasitoid fauna associated with seven leaf mining sawflies native in Hungary.
Material and Methods: For a period of four years (2011-2014), several leaf miner species were collected and placed in single mine rearings. From the leafminers, belonging to the Tenthredinidae family, a total of 809 mines made by 9 different species (Heterarthrus wuestneii, Fenusa dohrnii, Heterarthrus vagans, Fenusa pumila, Fenusella nana, Profenusa pygmaea, Metallus pumilus, Parna apicalis, Fenusa ulmi) were collected from 19 locations across Hungary.
Results and Conclusion: A total of 188 specimens of 13 parasitoid species belonging to 3 families (Braconidae - 1; Ichneumonidae - 1 and Eulophidae - 11) were reared out from our samples. Parasitoid adults were obtained from 7 of the 9 species of leaf mining sawfly hosts (Fenusa dohrnii, Fenusa pumila, Fenusa ulmi, Heterarthrus vagans, Metallus pumilus, Parna apicalis, Profenusa pygmaea). From Heterarthrus wuestneii and Fenusella nana no parasitoid adults emerged.The parasitoid species presented in this work are typically associated with leaf mining sawflies. Several new host-parasitoid associations have been described
Parasitoids of the Cypress Bark Beetle Phloeosinus bicolor (Brulle, 1832) (Coleoptera: Curculionidae) in Hungary
Ecphylus caudatus Ruschka, 1916, Spathius phymatodis Fisher, 1966 (both Hymenoptera: Braconidae) and Eurytoma blastophagi Hedqvist, 1963 (Hymenoptera: Eurytomidae) were found as new parasitoids of the invasive cypress bark beetle (CBB) Phloeosinus bicolor (Brune, 1832), synonym P. aubei (Perris, 1855) (Coleoptera: Curculionidae: Scolytinae). Ecphylus caudatus and Eurytoma blastophagi as well as Leluthia transcaucasica (Tobias, 1976) (Braconidae), also reared from P. bicolor, are new to the Hungarian fauna. The latter parasitoid species was found to be predominant in samples of P. bicolor collected from galleries of CBB in Budapest in the common juniper trees Juniperus communis L. (Pinales: Cupressaceae) in 2015-2016. A list of parasitoid species is presented and their possible importance for controlling the pest populations is discussed
A likelihood based comparison of population histories in a parasitoid guild
Little is known about the stability of trophic relationships in complex natural communities over evolutionary timescales. Here, we use sequence data from 18 nuclear loci to reconstruct and compare the intraspecific histories of major Pleistocene refugial populations in the Middle East, the Balkans and Iberia in a guild of four Chalcid parasitoids (Cecidostiba fungosa, Cecidostiba semifascia, Hobbya stenonota and Mesopolobus amaenus) all attacking Cynipid oak galls. We develop a likelihood method to numerically estimate models of divergence between three populations from multilocus data. We investigate the power of this framework on simulated data, and-using triplet alignments of intronic loci-quantify the support for all possible divergence relationships between refugial populations in the four parasitoids. Although an East to West order of population divergence has highest support in all but one species, we cannot rule out alternative population tree topologies. Comparing the estimated times of population splits between species, we find that one species, M. amaenus, has a significantly older history than the rest of the guild and must have arrived in central Europe at least one glacial cycle prior to other guild members. This suggests that although all four species may share a common origin in the East, they expanded westwards into Europe at different times. © 2012 Blackwell Publishing Ltd
Description of the first species of gall wasp (Hym., Cynipidae: Cynipini) and other unknown galls on Quercus macdougallii (Fagaceae)
Es descriu de Mèxic una nova espècie de cinípid de roures, Neuroterus chinanteco Pujade-Villar & Clark n. sp., coneguda només a partir de la seva generació sexual que indueix gales a les fulles de Quercus macdougallii Martínez (secció Quercus). Quercus macdougallii és una espècie poc coneguda, endèmica d’Oaxaca i poc comú (localitzada entre els 2700-3000 m), en perill d’extinció (inclosa a la Llista Vermella de la UICN). Es donen dades referents a la diagnosi, la distribució i la biologia d’aquesta nova espècie. Neuroterus chinanteco Pujade-Villar & Clark n. sp. representa la primera espècie esmentada en aquest hostatger. També s’il·lustren altres gales col·lectades en Q. macdougallii de les quals només s’han obtingut inquilins i/o parasitoides.A new species of oak gallwasp, Neuroterus chinanteco Pujade-Villar & Clark n. sp., known only from its sexual generation that induces galls on the leaves of Quercus macdougallii Martínez, (section Quercus) is described. Quercus macdougallii is a poorly known species,
endemic to Oaxaca and rare (located between 2700-3000 m a.s.l.), endangered (included in the IUCN Red List). Diagnosis, distribution and data on biology of the new species are given. Neuroterus chinanteco Pujade-Villar & Clark n. sp. represents the first species mentioned on this oak host. Other galls collected on Q. macdougallii from which only inquilines and/or parasitoids have been obtained are also illustrated
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