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.     

The preimaginal stages of Minotetrastichus frontalis (Nees) and Chrysocharis laomedon (Walker) (Hymenoptera: Eulophidae), parasitoids associated with Phyllonorycter issikii (Kumata) (Lepidoptera,Gracillariidae)

The biology and morphology of the early larval instars of Minotetrastichus frontalis (Nees) are redescribed and the morphology of the preimaginal stages of Chrysocharis laomedon (Walker) (Hymenoptera: Eulophidae) are described in detail for the first time. Both species are larval-pupal parasitoids of Phyllonorycter issikii (Lepidoptera, Gracillariidae), which is associated with Tilia sp. The female of M. frontalis lays her egg beside the host larva and the newly hatched first instar larva moves and has to find the host larva. The larva of P. issikii tries to continue its feeding but never pupates after paralysis. The female of C. laomedon lays its egg inside the cuticle of the larva of P. issikii, but the newly hatched parasitoid larva vacates the host larva and develops externally on its surface as an ectoparasitoid. Such behaviour might be facilitated by the constant temperature and humidity inside the mine. Some peculiarities of parasitoid–host relationships are described and discussed.     

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.     

Contrasting modes of handling moss for feeding and case‐building by the caddisfly Scelotrichia willcairnsi (Insecta: Trichoptera)

Final‐instar larvae of the microcaddisfly, Scelotrichia willcairnsi sp. nov. (Trichoptera: Hydroptilidae) were discovered feeding on a moss, Platyhypnidium muelleri in north‐eastern Queensland. Not only do the larvae feed on the moss, but their cases are constructed from fragments of moss leaves. Microscopic examination of larval guts and cases showed a total contrast in the angle at which the moss leaves are cut for each purpose: for cases the moss leaves are cut longitudinally, in parallel with the length of the cells, whereas for feeding the leaves are cut perpendicular to the leaf margin, across the cells, presumably an adaptation that releases the cell contents for digestion. The new caddisfly species is described based on the adult males. Scelotrichia willcairnsi represents the first Australian record of the South‐east Asian‐New Guinean Stactobiini genus Scelotrichia.     

The biology and early stages of Acampsis alternipes (Nees), with comments on the relationships of the Sigalphinae (Hymenoptera: Braconidae)

Details of the biology of the braconid subfamily Sigalphinae, based on rearings of Acampsis alternipes (Nees), are provided for the first time. A. alternipes is a solitary, koinobiont larval endoparasitoid of the geometrid moth Alsophila Hubner, though there is an external feeding phase prior to spinning a cocoon and pupation. Two features are of potential phylogenetic significance indicating a close relationship with the subfamily Agathidinae: (1) eggs are deposited in the host's nerve ganglia, and (2) the first instar larva is polypodiform. A. alternipes completes development in the autumn and overwinters as a fully eclosed adult within its cocoon, enabling it to emerge and search for hosts early in spring. The posterior of the eclosed adult within the cocoon is immersed in a viscous liquid that also surrounds the meconium. Chemical analysis of this liquid revealed that it comprises at least 25% glycerol and a further 25% consists of various fatty acid derivatives. Oviposition and developmental stages are illustrated. The overwintering behaviour of the agathidine braconid Earinus elator (Fabricius) is described and compared.     

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.     

The parasites of the psyllidae—3. Some notes on the biology and host relationships of Parapsyllae-Phagus Adulticolus Robinson (Hymenoptera)

Abstract

Parapsyllaephagus Adulticolus Robinson (CHALCIDIDAE: Encyrtinae) is an endoparasite of the adults of Psylla melanoneura Förster and Psylla subferrigenea Edwards. The life histories and biology of the hosts and parasite are described. Parapsyllaephagus adulticolus has five larval instars, which feed selectively upon the developing internal genitalia of the host at first, and eventually, as the final instar, upon the whole of the abdominal viscera. Pupation within the psyllid is followed by emergence of the adult parasite through the posterior dorsal surface of the abdomen of the host. The effect of these activities upon the migration of the adult psyllid from a winter shelter plant to a summer host plant is discussed and a relationship between the stimulus to migrate and the state of development of the internal genitalia is postulated. Some aspects of the orientation of the parasite larva within the host and the phenomenon of larval reversal are discussed.     

Bionomics,behaviour and immature stages of Pelecotoma fennica (Paykull) (Coleoptera: Rhipiphoridae)

Ptilinus fuscus (Anobiidae) was confirmed as the host species of Pelecotoma fennica (Rhipiphoridae, Pelecotominae). Females of Pelecotoma oviposit into the wood infested by the host larvae. First-instar larvae are elongate, unsclerotized, very different from the triungulinid larvae known in other rhipiphorids. They search actively for the host larvae in the wood; no phoresy is involved in the life cycle. The first-instar larvae temporarily paralyse the host larva and enter its body, overwintering (some perhaps more than once) as an endoparasite. In the spring of the year of emergence, the endoparasite engorges enormously (without moulting) and develops a special sclerotized caudal structure which is then used for perforation of the host's integument. The larva undergoes a further four ectoparasitic instars. The fifth (i.e. fourth ectoparasitic) instar differs considerably from the preceding three, and is capable of boring through the wood to prepare the emergence gallery for the adult. Pupation occurs in the wood. The rate of parasitization may locally far exceed 50%. Superparasitization by the first-instar larvae is possible, but usually only 1 larva survives to the ectoparasitic stage. Larval morphology of Pelecotoma is described and illustrated. Additional data on bionomics and larval morphology are also presented for the genus Metoecus (Rhipiphorinae). Comparing the biology and larval morphology of Pelecotoma with other Rhipiphoridae, it is assumed that ancestral rhipiphorids may have been xylophilous Tenebrionoidea with predaceous or omnivorous larvae, and that the ‘triungulinid’ larvae and phoretic habits may not belong to the groundplan of the family Rhipiphoridae. The widespread opinion considering Rhipiphoridae closely related to the family Mordellidae is questioned.     

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.     

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 morphology and biology of Pterodunga mirabile Daccordi,an unusual subsocial Chrysomeline (Coleoptera: Chrysomelidae)

New information is provided on the morphology and biology of the Australian leaf‐beetle Pterodunga mirabile Daccordi. This species is unusual in the Chrysomelinae for the following features: adult with deeply grooved prothoracic hypopleuron, laterally pointed elytral margins, concealed mesoventrite and fused abdominal ventrites; female ovoviviparous and without spermatheca; first‐instar larva with lappet‐like sclerites; maternal care; host plant in the Proteaceae. The systematic position and conservation status of Pterodunga are discussed. Maternal care in the Chrysomelinae and Proteaceae‐feeding in the Chrysomelidae are reviewed. The first record of maternal care in Chrysomelinae, for Labidomera suturella Guérin‐Méneville, is shown to be a misidentification of Platyphora selvae Daccordi.     

Studies on Gasteroclisus rhomboidalis (Boheman.) (Coleoptera: Curculionidae)—a pest of the African ‘spinach’

Summary

Eggs of G. rhomboidalis are usually laid singly in separate excavations made with the snout of the beetle in either leaf petioles or tender portions of shoots of host plants, Amaranthus sp. At field temperatures fluctuating between 19°C and 30°C and in contact with water, eggs hatched in a mean of 2·8 days while unmoistened ones shrivelled up.

Beetle larvae bore and feed on the stele of host plants where development, up to adulthood, is completed in self-made larval galleries. On the average, the larvae are capable of consuming 40% and above of the cross-sectional areas of stems of infected host plants. In nature, multiple infection of host plants was quite common with 1–16 beetle larvae/plant rather usual. Consequently, the stem of virtually every healthy-looking host plant is internally traversed by larval galleries, at times even below ground level.

Adults bite their way out of the stem after a mean of 36·37 days from date of oviposition.

Larval damages to host plants are the gravest and bring about premature breakage and/or death of crops, stunted growth and reduced yield of the wanted leaf products.     

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.     

Gall‐induction by an Australian insect of the family Thripidae (Thysanoptera: Terebrantia)

Leaf‐fold galls induced by Cyrilthrips cecidis gen. nov. et sp. nov. on Austrosteenisia blackii (Fabaceae) in eastern Queensland, Australia, involve either single or double folds. Single‐fold galls are subject to invasion by two species of kleptoparasitic Phlaeothripidae, to which double‐fold galls are largely immune. This thripid is a member of a southeast Asian lineage of Thripinae in which gall‐induction is possibly recurrent. This lineage includes the genus Chaetanaphothrips in which some species are crop pests but not gall‐inducing. Females of Cyrilthrips have a unique curved spur on the hind coxae, and the ocellar chaetotaxy is also unique among Thripidae.     

The morphology and biology of the entomophilic Thripinema fuscum (Tylenchida: Allantonematidae), and the histopathological effects of parasitism on the host Frankliniella fusca (Thysanoptera: Thripidae)

We used light and electron microscopy to detail the in vivo life cycle of the nematode Thripinema fuscum and to determine the effects of parasitism on tissues of the thrips host Frankliniella fusca. The parasitic T. fuscum female produced eggs within 4–5 days after ingress and the host haemocoele became packed with eggs and developing juvenile nematodes. Mature juveniles migrated to the hindgut and fully developed juveniles first emerged from the posterior end of the male or female F. fusca 9 days after parasitization. Parasitization induced a displacement of the host alimentary tract, an atrophy of the ovaries and fat body, and an alteration of energy and waste reserves in host tissues. Our observations reveal a specialized relationship showing that this parasite is well adapted to exploit the host digestive, reproductive and excretory systems.     

Life cycles and host–parasitoid relationships of five species of Leucospis wasps in Argentina (Hymenoptera: Leucospidae)

The genus Leucospis Fabricius is comprised of parasitoid wasps relatively uncommon in nature. Their immature stages develop on aculeate Hymenoptera, in particular solitary bees, but hosts are known for only around 25 Leucospis species (about 20% of 115–120 world species), so the true relationship of this family with bees is largely unknown. Here we report on individuals of five species of Leucospis wasps which emerged from nests of different bee and wasp species during distinct sampling periods during a trap-nesting programme, in two contrasting areas: agro-ecosystems and natural habitats in the Pampean region. Some of these nests were parasitised by L. cayennensis Westwood, L. coxalis Kirby, L. egaia Walker, L. pulchriceps Cameron and L. signifera Bou?ek. Our results expand the available information of host species for L. cayennensis, L. coxalis, L. egaia and L. pulchriceps and represent the first record of hosts associated with L. signifera. The hosts were only bee species of the genera Centris, Tetrapedia (family Apidae) and Megachile (Megachilidae). These species were more abundant in the natural reserve than in agro-ecosystems, suggesting that anthropogenic activities could negatively affect their populations. Most nests were attacked in one (43.7%) or two (40.7%) cells, but the remaining nests (16.5%) had more (up to seven cells). However, the position of the attacked cells was variable, suggesting that females of Leucospis species oviposit in recently built cells, and that the hatching of larvae is delayed, or that the first larval stage waits until the host larva reaches a sufficient size to attack.     

Seasonality and abundance of Metamasius callizona (Coleoptera: Dryophthoridae), an invasive insect herbivore,on two species of Tillandsia (Bromeliaceae) in Florida

Seasonality and abundance of an insect herbivore population are regulated by a complex array of forces from the bottom up, from the top down, and from competition and the environment. This paper examines the effect that two host plants have on an insect herbivore in the absence of top‐down regulation or competition. Metamasius callizona is an invasive bromeliad‐eating weevil in south Florida that has escaped its natural parasitoid in its home range. A 4‐year field study shows the weevil to be present and active year‐round, but to exhibit different patterns of seasonality and abundance on two of its host plants. It is argued that this demographic variability is generated by the differences in leaf type and growth habit that exist between the two host plants.