The parasitoid complex attacking coexisting Spanish populations of Euphydryas aurinia and Euphydryas desfontainii (Lepidoptera: Nymphalidae,Melitaeini)

We report on a five‐year investigation of the complex of parasitoids associated with coexisting populations of Euphydryas aurinia and Euphydryas desfontainii at a Spanish site. A sample of over 7000 eggs, 1000 larvae and 200 pupae (the last of these in part having been experimentally placed) revealed the existence of no egg parasitoids, of three primary larval parasitoids and of five primary pupal parasitoids, plus 13 secondary and facultatively tertiary parasitoids associated with the cocoons of the main larval parasitoid, the specialist Cotesia sp. D. The most abundant secondary parasitoid, Neochrysocharis albiscapus, entirely escaped tertiary parasitism by being gregarious. The mortality induced by parasitoids on the butterfly populations, although heavy, was clearly partially minimized by secondary parasitoids acting on Cotesia sp. D. The striking coincidence of the parasitoid complexes attacking the two Euphydryas species suggests a good system for investigating apparent competition between hosts sharing common natural enemies.     

Anatomy,reach and classification of the parasitoid complex of a common British moth,Anthophila fabriciana (L.) (Choreutidae)

The small plurivoltine moth Anthophila fabriciana is widespread and often abundant in Britain wherever its main larval foodplant, stinging nettle, occurs. It overwinters as a larva (first generation) then has one or more partly overlapping summer broods (notionally second generation). A total of 5017 larvae were collected and reared from widely distributed populations in Britain, and the resulting 2167 host mortalities due to parasitoids were assessed. Small collections of pupae were also made. Altogether 25 parasitoid species, including secondary parasitoids, were found. Larval parasitism was heaviest in the second generation. In each generation there was a dominant parasitoid that was absent from the other. Summary information on the developmental biology and host range (expressed quantitatively and resulting from very broad rearing programmes) for each parasitoid is given. They are classed as ‘absolute specialists’, ‘taxon oligospecialists’, ‘niche oligospecialists’, ‘niche generalists’, ‘casuals’ and ‘strays’. Both kinds of oligospecialists can be ‘paraspecialists’ if only one potential host occurs locally. Although constructing a quantitative food web is not appropriate, providing both source web and sink web data in quantitative form enables the parasitoid complex to be understood in the wider context of the ecosystem, necessary for both biodiversity and nature conservation interests. In Appendix 1, parasitoids reared from other European Choreutidae are listed quantitatively.     

The food web of parasitoid wasps and their non-phytophagous fly hosts in birds' nests (Hymenoptera: Chalcidoidea,and Diptera: Cyclorrhapha)

We present a food-web study of the parasitoid wasps and their fly hosts found in the nests of cavity-nesting songbirds. This birds' nest parasitoid web is different from all parasitoid webs studied comprising exclusively non-phytophagous host species. A total of 490 nests were examined for host occurrence, abundance and parasitism rates. Thirty-two species of potential hosts and 10 species of parasitoid wasps were recorded in nests from 25 sites in northern Germany and from two additional sites in south-western Germany. Most of these species were rare and unspecialized. The only very common parasitoid was Nasonia vitripennis (Chalcidoidea: Pteromalidae). The records of 14 regular host species from northern Germany, which are connected to all 10 parasitoid species, were used for further calculation of food-web statistics. The parasitoid communities in birds' nests were compared with other known parasitoid communities. The birds' nests exhibited a lower species richness compared with communities of phytophagous hosts, but showed similarities with communities of necrophagous or coprophagous hosts, or of parasitoid hosts. The parasitism rate was comparable in all host–parasitoid-systems, supporting the idea that the parasitism rate is independent of species richness.     

Alipumilio (Diptera: Syrphidae) fly association with Burseraceae tree resins in the eastern Brazilian Amazon

Numerous fly (Diptera) larvae develop in plant saps or rotting exudates, but few have adapted to resin flows of trees. Among these are some primitive syrphid genera (Syrphidae), Cheilosia in the temperate region and Alipumilio in the neotropics. A recent study of resin harvest in the eastern Brazilian Amazon has revealed a potentially new species of Alipumilio that develops in resin lumps on some species of Burseraceae trees. These resin flows are primarily stimulated by larvae of a bark-boring Sternocoelus weevil (Coleoptera: Curculionidae). This fly larva's morphology, movement in the resin and unsuccessful rearing apart from fresh resin indicate it may be consuming microbial spores or sap materials coming out of tree wounds. While Sternocoelus weevils are found in resin lumps in a range of Protium and other Burseraceae species in the region, Alipumilio larvae were only found in the resin of some of these species. The study speculates that some trees do not support Alipumilio because their resin's chemical properties are inhospitable to these larvae or inhibit the micro-organisms that they feed on.     

The parasitoid complex and parasitoid‐induced mortality of spiders (Araneae) in a Central European woodland

The parasitoid complex of spiders was studied in three different sites of a forest and, for comparison, in open habitats in north‐western Lower Saxony (Germany). Qualitative data and, for four spider species, detailed quantitative rearing data were obtained. At least 25 parasitoids of spiders were recorded (23 species of Hymenoptera and two species of Diptera). External parasitoids of spiders were rare in the woodlands; only up to 1% of the spiders collected by hand searching and sweep netting had ectoparasitoids. During the investigation 23 parasitoid species were reared from spider egg masses, 10 of them occurring in woodlands. Two species were secondary parasitoids. Several parasitoid–host relationships were recorded for the first time. Egg masses of Floronia bucculenta were parasitized up to 5% by two species of the genus Gelis. Up to 10% of the egg masses of Linyphia hortensis were parasitized by Aclastus species. Egg masses of the spider genus Ero were parasitized by three species, causing an overall mortality of 40%. For egg masses of Agroeca spp. parasitization at some locations was up to 60%. An overview of the Central European parasitoid complex of spiders is provided.     

Aphidiinae parasitoids (Hymenoptera: Braconidae) of Macrosiphoniella aphids (Hemiptera: Aphididae) in the western Palaearctic region

The parasitoids (Hymenoptera: Braconidae: Aphidiinae) of Macrosiphoniella del Guercio (Hemiptera: Aphididae) from the western Palaearctic region are reviewed and keyed. The host associations and distribution of each species are summarized. Aphidius stigmaticus sp. nov. reared from Macrosiphoniella tanacetaria on Tanacetum polycephalum, which is another member of the Macrosiphoniella aphid parasitoid guild from high-mountain habitats in western Iran, is described in the present contribution. Some taxonomic problems within Macrosiphoniella parasitoid guilds are discussed as well.     

Altitudinal patterns of abundances and parasitism in frugivorous drosophilids in west Java,Indonesia

Abundances and parasitism rates of frugivorous drosophilid flies were studied in three localities at altitudes of 250–1350 m in and near Bogor, Indonesia. The drosophilid and parasitoid species were classified into four groups: low-altitude species, high-altitude species, species abundant at a mid-altitude location and species occurring rather evenly from low to high locations. The ananassae and immigrans species groups were major drosophilids collected. All species of the ananassae species group were more abundant at lower altitudes, and the parasitism rate in this species group decreased with increasing altitude. Thus, the host abundance seems to affect the parasitism rate. On the other hand, the rate of parasitism in the immigrans species group showed no apparent relation with altitude or density, possibly due to the fact that species of this species group varied in altitudinal distribution. It is also suggested that the diversity of drosophilid species affects the composition of parasitoid species.     

The biology and immature stages of Thrybius togashii Kusigemati (Hymenoptera: Ichneumonidae: Cryptinae), with a description of the male

Thrybius togashii Kusigemati is found to be an ectoparasitoid of larvae of a phytophagous eurytomid, Tetramesa sp. (Hymenoptera), growing gregariously in internodal cavities of reeds (Phragmites japonica Steud.), in Japan. The female of T. togashii oviposits into reed canes and its predaceous larva consumes almost all eurytomid larvae in an internodal cavity. This species is bivoltine. The mode of parasitism of this species is unique in some respects. First, when the female oviposits, no food resources are available in the reed. Second, the parasitoid allows part of the host larvae to grow and exploits increasing food resources. The egg, pupa and first to final instar larvae and adult male are described and figured for the first time. Colour dimorphism in both sexes and adult morphology adapted to habitat and ovipositional substrate are also discussed.     

An Australian stiletto fly (Diptera: Therevidae) parasitised by a bee fly (Diptera: Bombyliidae)

Exechohypopion therephaga sp. nov. (Bombyliidae) emerged from the pupa of Parapsilocephala ambocerina sp. nov. (Therevidae) collected near Wentworth, New South Wales, Australia. The adults, pupae and mature larvae of the bombyliid and therevid are described and illustrated. Because the therevid host was collected from soil as a larva, the first instar bombyliid planidium is presumed to attach to the therevid in the larval stage. This is the second known record of a therevid being parasitised. Both known cases occurred in Australia and involved a bombyliid parasitoid.     

Generalist hymenopteran parasitoids of the leaf-miner Chromatomyia fuscula (Zett.) (Dipt.: Agromyzidae)

In southeastern Norway, by the last week of June (1992), 48%of Chromatomyia fuscula emerged, based on the number of mines collected from Hordeum vulgare leaves. Among the parasitoids Diglyphus begini was the dominant species, but Cirrospilus vittatus and Neochrysocharis aratus also emerged in significant numbers. During June and July, N. aratus was the dominant species in the 1st and 2nd leaves, but D. begini was dominant in the 4th to 6th leaves. C. vittatus and Cyrtogaster vulgaris affected all larvae of the leaf-miner fly, living on various leaves. In central Norway, 48% of C. fuscula also emerged. C. vulgaris and D. begini were the dominant parasitoids and C. vittatus was also found. C. fuscula has no specialist parasitoids. Adults of the generalist parasitoids of the leafminers always search for different hosts. In investigation of the parasitoid complex of a lepidopteran leaf-miner, Phyllocnistis labyrinthella (living in Populus tremula leaves at the edge of the examined barley field), three shared parasitoids (C. vittatus, Pnigalio soemius and Pnigalio pectinicornis) were found. The complex network of host plant-phytophagous insect-insect parasitoid-facultative hyperparasitoid relationship is discussed.     

On the parasitoid community of Aulacidea laurae (Hym., Cynipidae), with description of a new species of Adontomerus (Hym., Torymidae)

An account is given of parasitoids (Hym., Chalcidoidea) reared from Spanish galls of Aulacidea laurae (Hymenoptera, Cynipidae) which develop in achenes of Scorzonera laciniata (Asteraceae). The parasitoid community includes Adontomerus brevicaudatus (Hym., Torymidae) which is described as new. Final instar larva of the new species is also described. The generic placement of A. brevicaudatus and the composition of the parasitoid community are discussed.     

New damselfly hosts and species identification of an aquatic parasitoid Hydrophylita emporos (Hymenoptera: Trichogrammatidae) in Taiwan

ABSTRACT

The host–parasitoid relationship and species identity of aquatic parasitoids of two damselflies Coeliccia cyanomelas (Platycnemididae) and Psolodesmus mandarinus dorothea (Calopterygidae) from Fushan and Lienhuachih in Taiwan were studied using morphological characters and DNA barcoding sequences. The parasitoids reared from the damselflies’ eggs, and the field-collected parasitoids, were morphologically identified as Hydrophylita emporos (Trichogrammatidae), a recently described parasitoid of the damselfly P. m. mandarinus from Northern Taiwan. The CO1 (cytochrome c oxidase I) gene tree supported the identification as H. emporos, as well as all parasitoid samples from C. cyanomelas, P. m. dorothea and P. m. mandarinus. The sampled H. emporos populations did not differ genetically despite their different host associations. However, some genetic differences were found between H. emporos populations from Northern and Central Taiwan, indicating that the dispersal of H. emporos may be limited by geographical distances. Our results suggest that H. emporos can parasitise not only closely related sister subspecies, P. m. mandarinus and P. m. dorothea, but also phylogenetically distant species of another damselfly family, C. cyanomelas. This is the first record of multiple damselfly hosts for the aquatic parasitoid genus Hydrophylita. This finding implies that the host range of H. emporos and congeneric species may be broader than previously thought.     

A remarkable new species of scuttle fly (Diptera: Phoridae) whose larvae infest chickpea root nodules in India

Metopina ciceri sp. nov. is described on the basis of males with reduced wings, fully winged females, blind females with reduced wings, pupae and larvae. The larvae infest the root nodules of the chickpea, Cicer arietinum L. The blind-morph females are considered to be congeneric with the type species of the genus Typhlophorina Silvestri and this genus is synonymized with Metopina. The males, if procured in isolation, would have been assigned to a separate genus. The evolution of sexual dimorphism and dimorphic females in M. ciceri is discussed in relation to a speculative scenario involving juvenile hormone and heterochrony. It is also speculated that dispersal is undertaken by the sighted fully-winged female morph only. These speculations and the question of whether the infestation of C. arietinum by M. ciceri affects yield remains to be investigated.     

Homichloda barkeri (Jacoby) (Coleoptera: Chrysomelidae: Alticinae), a candidate agent for the biocontrol of prickly acacia,Acacia nilotica (Mimosaceae) in Australia

The status of Homichloda barkeri (Jacoby) n. comb. is discussed. A key is presented to four Afrotropical Homichloda species, including fulva n. sp. The eggs, larvae and pupae of H. barkeri are described for the first time. Unusual adult and immature stage characters are discussed in relation to the placement of Homichloda in the Alticinae.     

Distinct parasitoid communities associated with host races of the leaf-mining moth Acrocercops transecta on distantly related host plants (Juglandaceae and Ericaceae)

Differences in host-plant species may affect the structure of parasitoid communities of phytophagous insects. Phytophagous insect species often consist of host races, and comparisons between host races enable us to infer the effects of host-plant differences on parasitoid communities. Here, we compare the parasitoid fauna of two host races of the leaf-mining moth Acrocercops transecta, which are associated with either Juglandaceae or Lyonia ovalifolia (Ericaceae). Field collection and subsequent laboratory rearing revealed a significantly higher parasitization ratio in the Juglandaceae race than in the Lyonia race. In the Juglandaceae race the majority of parasitoids were Braconidae, whereas in the Lyonia race the majority were Eulophidae. Furthermore, even within the same host race the most abundant parasitoid species differed between populations with different host associations. Hence, the present results strongly indicate that different host-plant taxa affect the structure of parasitoid communities even within a single phytophagous insect species.     

Parasitoids of larch sawfly,Pristiphora erichsonii (Hartig) (Hymenoptera: Tenthredinidae) in Changbai Mountains

Eight parasitoids, Cleptes semiauratus (L.) (Chrysididae), Himerta impuncta Sheng, Polyblastus (Labroctonus) westringi Holmgren, Olesicampe erythropyga (Holmgren), Campodorus sp. and Mesochorus sp. (Ichneumonidae), Tritneptis lophyrorum (Ruschka) (Pteromalidae) and Myxexoristops sp. (Tachinidae), reared from cocoons of Pristiphora erichsonii (Hartig) (Hymenoptera: Tenthredinidae) in Changbai Mountains, Jilin Province in 2009–2010, are reported. Four hyperparasitoids of P. erichsonii, Phygadeuon bidentatus (Uchida) and Phygadeuon rugulosus Gravenhorst and Trichopria sp. (Diapriidae) reared from Myxexoristops sp., Phygadeuon sp. reared from C. semiauratus, are reported for the first time. The account ratio of Chrysididae, Ichneumonidae, Tachinidae and Pteromalidae was 59.5, 5.6, 32.4 and 2.4%, respectively. The parasitism rates of parasitoids of P. erichsonii were 31.5% in May 2009, 19.8% in October 2009 and 15.9% in June 2010. The emergence periods of parasitoids were from 16 May to 7 June 2009.     

Notes on Simulium ovazzae Grenier and Mouchet (Diptera: Simuliidae) and river crabs (Malacostraca: Potamidae) and their association

Summary

Collections of crabs in the forest zone of West Cameroon produced three species—Potamonautes africanus, P. orthostylis and P. pobeguini. The P. africanus carried populations of immature Simulium ovazzae.

Analysis of crabs collected by hand and those collected in traps indicates very little overlap in the sizes of the crabs obtained by the two techniques. This problem is discussed.

The infestation rates of S. ovazzae on P. africanus were found to be highest on medium-sized crabs. The attachment sites of the S. ovazzae on the crabs were found to vary with both the size of the crab and the size of the Simulium larva.

The size distributions of S. ovazzae larvae on small crabs were found to be different from those on medium and large crabs. The characteristic deficiency of smaller larvae on medium and large crabs reported for other crab-phoretic species was also found with S. ovazzae but the smaller crabs showed a deficiency of larger larvae. A hypothesis is put forward to explain the dearth of larger larvae on the smaller crabs and the higher infestation rate on medium crabs.

S. ovazzae are shown to arrive on their hosts as single larvae carried by the current.

Six adult S. ovazzae were reared from pupae in the laboratory. Small numbers of presumed S. ovazzae biting man in Cameroon are reported.     

Biology of Lissoderes Champion (Coleoptera,Curculionidae) in Cecropia saplings inhabited by Azteca ants

This paper provides an account of the biology of Lissoderes (Coleoptera, Curculionidae, Conoderinae) focusing on L. pusillus Hespenheide and L. subnudus Champion. The eggs, larvae, and pupae live inside the hollow stems of Cecropia saplings. Adult weevils chew through the stem and deposit eggs on the inner surface of the internode. The larvae feed on the parenchyma lining the hollow internodes and pupate inside the internode. Emerging adults chew their way out of the stem. Two hymenopteran parasitoids were reared from larvae and prepupae of L. pusillus: Neocatolaccus sp. (Pteromalidae) and Heterospilus sp. (Braconidae). Menozziola sp. (Diptera, Phoridae) and Conoaxima sp. (Hymenoptera, Eurytomidae) were observed parasitizing Azteca queens. Parasitism by these species may explain part of the high mortality observed in colonizing Azteca queens. Direct competition with L. pusillus and L. subnudus appears not to be a major cause of queen mortality, although possible indirect effects of the weevils remain unknown.