The ovipositor apparatus of basal Hymenoptera (Insecta): phylogenetic implications and functional morphology

The skeleto‐musculature of the ovipositor apparatus and the external sculpture of the 1st and 2nd valvulae was studied in representatives from all ‘symphytan’ families. Nineteen informative characters were coded and scored. The distribution of character states are discussed with reference to recent cladistic treatments of the Hymenoptera. Putative autapomorphies of the Hymenoptera are the presence of cordate apodemes on T9 and basal articulations and associated musculature between the 2nd valvifers and the 2nd valvulae. It is a ground plan feature of the order to have the gonocoxites of abdominal segment 8 fused with the gonangula. The configuration of the musculature of the ovipositor apparatus did not display much variation among the taxa examined, except within the Pamphilioidea. There is considerable variation in the external ovipositor sculpture within the Tenthredinoidea. Putative synapomorphies for the tenthredinoid families except the Blasticotomidae are the presence of alternating strongly and weakly sclerotized zones on the first and/or second valvulae and the presence of serrulae on the sawteeth. The presence of transverse rows of large ctenidia on the 1st valvulae is an autapomorphy of the Diprionidae. Fusion of the 2nd valvifers and the 3rd valvulae is a synapomorphy for the Argidae + Pergidae. The ovipositor apparatus of the Pamphilioidea is highly derived, putative autapomorphies being the close association between T9 and the first valvifers, the reduction of the distal parts of the 1st valvulae, and the fusion of the 2nd valvulae for their entire length. The changes in the ovipositor apparatus of Pamphilioidea are associated with a decrease in the amount of work it has to perform during ovipositing, as the eggs are placed predominantly externally on the substrate. The ovipositor apparatus of the ‘Siricoidea’ is enlarged and modified for ovipositing into wood. Putative synapomorphies of the ‘Siricoidea’ + Orussidae + Apocrita are the presence of sawteeth only distally on the ovipositor and elongation of the cordate apodemes of T9.     

The old wasp and the tree: fossils, phylogeny and biogeography in the Orussidae (Insecta, Hymenoptera)

The phylogenetic relationships of the fossil orussid taxa Mesorussus taimyrensis and Minyorussus luzzi are examined by analysing them together with a large data set compiled previously for the extant Orussidae. The fossils are placed in an unresolved trichotomy with the extant Orussidae. The phylogeny is used for evaluating the hypothesis that the ancestors of the family had reduced body size; the results of this analysis are inconclusive. The biogeographical history of the Orussidae is explored. The common ancestor of the family was probably widespread, the initial splitting events taking place prior to or coinciding with the separation of Laurasia from Gondwana. Later putative vicariance events can be correlated with the gradual breakup of Gondwana. However, the biogeographical history of the Orussidae is dominated by speciation within regions and dispersal. The minimum age of the common ancestor of the Orussidae is >180 Myr when estimated from the biogeographical pattern, >95 Myr when estimated from the phylogenetic position of the fossils; the earlier date is considered to be the most likely.  © 2004 The Linnean Society of London , Biological Journal of the Linnean Society , 2004, 82 , 139–160.     

Ichneumon wasps of the Khasurty locality in Transbaikalia (Insecta, Hymenoptera, Ichneumonidae)

One new genus and four new species of ichneumon wasps are described from the Lower Cretaceous of Buryatia (Khasurty locality): Amplicella mininae, sp. nov., A. shcherbakovi, sp. nov., A. bashkuyevi, sp. nov., Khasurtella buriatica, gen. et sp. nov. The species Tanychora sinensis Zhang, 1991 is transferred to the new genus Khasurtella. Similarity of the ichneumonid faunas of Khasurty and the Chinese localities Yixian and Laiyang indicates the age similarity between these localities. Identification key to genera and species of Tanychorinae is given.     

Johnston's organ in Neodiprion sertifer (Insecta: Hymenoptera)

The fine structure of Johnston's organ in the pine sawfly, Neodiprion sertifer, was studied by electron microscopy to determine if there exists a dimorphism in this organ corresponding to the sexual dimorphism in antennal shape and surface area. The organ is made up of scolopidia that are ultrastructurally similar to those of other insects. The scolopidia, identical in both sexes, comprise three sensory cells bearing two types of sensory processes: Two are shorter and smaller in diameter than the third, which extends into the cuticle of the membrane connecting pedicel and flagellum and terminates at an epicuticular invagination. The dendrites and sensory processes are surrounded by two types of enveloping (glial) cells-a scolopale cell and an attachment cell. Other enveloping cells occur at different levels of the scolopidium. Sexual dimorphism is evident only in the numbers of scolopidial groups: Males have more groups with fewer scolopidia, but both sexes possess about the same total number of scolopidia.     

New maimetshid wasps in Cretaceous amber from Myanmar (Insecta: Hymenoptera)

The extinct, exclusively Cretaceous wasp family Maimetshidae is newly recorded from Earliest Cenomanian Burmese amber. Two new genera and species are described. Burmaimetsha concava gen. et sp. nov., based on a male and a female, is most similar to Guyotemaimetsha Perrichot, Nel & Néraudeau, from Albian-Cenomanian French amber, but differs in its larger mandibles, distinctly concave face, elongate antennomeres, and forewing with cell [1Rs] smaller and fourth abscissa of Rs shorter. Maimetshasia kachinensis gen. et sp. nov., is based on a male, and is characterized by asymmetric mandibles with two and three teeth, by its forewing venation without cross-vein 2rs-m, with cell [1M] large and trapezoidal, and vein 2Rs + M very short, and by the hind wing without a free apex of Rs. The family was evidently widespread in the Cretaceous, and the new records extend the paleobiogeographical range to the South-East of Eurasia. A discussion about the possible biology of Maimetshidae is provided.     

Cocoon silk chemistry in parasitic wasps (Hymenoptera, Ichneumonoidea) and their hosts

Bulk amino acid compositions of larval cocoon silks of 24 species of ichneumonoid parasitic wasps, representing 13 subfamilies that kill the host in a larval or prepupal stage, are compared with those of their hosts to test the hypothesis that amino acid compositions of major protein products should, in certain cases, be similar on energetic grounds. Although substantial variation in amino acid composition was found among both parasitoids and hosts, suggesting the production of different types of silks, no significant general matching was detected. However, the trend in the degree of similarity observed was in the direction predicted by a priori consideration of the nature of the parasitoid – host association. Lack of a general association may be explained by the very simple silk glands of the parasitic wasps and by the fact that, in most cases, their hosts are not completely consumed at a time when they are likely to contain any large reserves of silk proteins. The three species of Cotesia (Braconidae: Microgastrinae) investigated stood out in that their silks showed considerable interspecific variation in molar percentage amino acid composition, and this might be associated with their apparent utilization of α-helical silks rather than fibroins.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 81 , 161–170.     

Ovipositor internal microsculpture and other features in doryctine wasps (Insecta, Hymenoptera, Braconidae)

Detailed ovipositor morphology has been investigated in representatives of 81 of the more than 120 genera of the parasitic wasp subfamily Doryctinae. Potentially phylogenetically informative variation was found in the microsculpture of the egg canal wall and the presence and degree of development of the valvillus. In all the genera, a socketed seta arises from below each member of the line of ctenidia (comb-like scales) distal to the valvillus (or valvillar region). These subctenidial setae are modified in two groups of genera. In the Holcobraconini (= Odontobraconini) together with the genera Acanthodoryctes, Binarea, Monarea , and Liobrucon , the setae are extremely flattened producing overlapping leaflet-like structures. In some of these, groups of leaflets are further modified to form fans that protrude into the egg canal. In Schlettereriella and Leptospathius the basal seta is highly branched and rather flattened and may serve a similar function to the valvillus which in these two genera is extremely reduced. In Doryctes and Neodoryctes , there is a distinctive type of bar-like sculpture anterior to the valvillus and a single large crescentic bar posterior to the valvillus. These modifications are suggested as possible synapomorphies (in lieu of an analysis) for their respective groups of genera. Several other characters are also described and illustrated. CO 1998 The Norwegian Academy of Science and Letters     

Morphology and ultrastructure of a secretory region enclosed by the venom reservoir in social wasps (Insecta,Hymenoptera)

The morphology and ultrastructure of the convoluted gland inside the venom reservoir of four species of social Vespidae are described. The cells of the venom gland (including the convoluted gland) can be divided into six groups: (1) epithelial cells, (2) glandular cells with the end apparatus secreting into the tubule inside the convoluted gland (internal or embedded tubule), (3) a continuous arrangement of glandular cells with the end apparatus secreting directly into the venom reservoir, (4) glandular cells that are loosely dispersed along the tubule lumen between the free tubules and the embedded tubule of the convoluted gland, (5) secretory cells of the free tubules and (6) duct cells. One kind of secretory cell, hitherto unknown and described in this paper (group 3), is characterized by the presence of a well-developed end apparatus, usually with enlarged extracellular spaces, but lacking the normally associated duct cells. The secretory cells contain several stacks of granular endoplasmic reticulum, but these are mainly concentrated in the middle of the cell. The basal half of the cells contains many lipid droplets. Although the function of the convoluted gland is not yet understood, an hypothesis is related to what is known of the function of reservoir secretory cells in solitary wasps. All wasp species studied showed the same organization of the convoluted gland, which clearly distinguishes their venom gland from that of Sphecidae.     

Venom gland and reservoir morphology in the Doryctinae and related braconid wasps (Insecta, Hymenoptera, Braconidae)

Detailed venom reservoir and venom gland intima morphology has been investigated in reprsentatives of 84 genera and 10 subfamilies of Braconidae with particular reference to the Doryctinac, basal cyclostomes and related groups including the Opiinae, Alysiinae and Rogadinae sens. lat . Several new phylogenetically significant characters are described and illustrated. Extcnsivc secretory ductules on the primary venom duct is suggested as a synapomorphy for the subfamilies Braconinac, Doryctinae, Opiinae, Alysiinae and Gnamptodontinae. The presence of two separate venom gland insertions and their position beyond the spiral sculpture of the reservoir are suggested as synapomorphies for the subfamilies Doryctinae and Ypsistocerinac. An anterior, weakly sclerotized, probably glandular. expansion of the reservoir characterizes the Histeromerinae and Rhyssalinae and also the enigmatic genera Thoracoplites Fischer and Doryctomorpha Ashmead which are hcre transferred to the Rhyssalinae. Within the Doryctinac, venom reservoir morphology suggests three generic groups, one comprising the genera of the Odontohraconini and possibly also the genera Acanthodoryctes , Binareu and Monarea , all of which have an essentially undivided reservoir with extremely fine and uniform spiral sculpture. the second comprising the genera Doryctophasmus , Euscelinus, Gildoria, Halycea and Schlettereriella , which share horn-like processes at the base of the venom duct insertions, and a third including Acrophasmus. Dendro- soter, Heterospilus, Megaloproctus, Rutheia, Paraspathius, Schlettereriella. Spathius and Syngaster based on the presence of two markedly different densities of annulation of the reservoir. The degree to which external and other characters support these groups is discusscd.     

Functional significance of variation in the shape of mandibles,wings, ovipositor,and abdomen in chalcidoid wasps (Hymenoptera,Chalcidoidea)

In parasitic chalcidoid wasps, the shape of mandibles, the degree of wing development, and the configuration and length of the ovipositor depend on adaptations to the solidity of the host mummy integument, peculiarities of the host search, oviposition into unprotected or protected hosts, and of the host size.     

New data on chromosomes of parasitic wasps of the subfamily Ichneumoninae (Hymenoptera,Ichneumonidae)

The new data on chromosomes of parasitic wasps of the subfamily Ichneumoninae: Centeterus major (2n = 22), Diadromus troglodytes (2n = 22), D. varicolor (2n = 22), Tycherus infimus (2n = 22), Cratichneumon rufifrons (2n = 26), Eristicus clarigator (2n =.26), and Ctenichneumon funereus (2n = 16) were obtained. Some aspects of the chromosomal variability of Ichneumoninae are discussed.     

Simultaneous analysis of basal Hymenoptera (Insecta): introducing robust-choice sensitivity analysis

Molecular characters are analysed on their own and in combination with morphological data to examine the phylogenetic relationships of the basal lineages of Hymenoptera ('Symphyta'). This study covers 47 sawfly genera and nine apocritan families and includes molecular sequences from five genes − 12S, 16S, 18S and 28S ribosomal genes and cytochrome oxidase 1 − as well as 343 morphological characters. A robust-choice sensitivity analysis is performed with the data. First, the simultaneous analysis is repeated three times, each time employing a different step matrix for weighting the transformations of the molecular characters. Then, the results of all three simultaneous analyses are summarized in a strict consensus in order to avoid basing the conclusions on a narrow set of assumptions. This methodology is discussed in the paper. The relationships among superfamilies largely confirm previous hypotheses, being (Xyeloidea (Tenthredinoidea s.l. (Pamphilioidea (Cephoidea (Siricoidea (Xiphydrioidea (Orussoidea Apocrita))))))), where Siricoidea is understood as Siricidae+Anaxyelidae. However, the relationships within Tenthredinoidea s.s. proposed here are novel: ({Argidae Pergidae}[ Athalia {(Diprionidae Cimbicidae) Tenthredinidae minus Athalia }]).  © 2003 The Linnean Society of London . Biological Journal of the Linnean Society , 2003, 79, 245–275.     

Phylogeny and classification of the extant basal lineages of the Hymenoptera (Insecta)

The phylogeny of the basal hymenopteran lineages, including representatives of all ‘symphytan’ families, is anal; In total, 236 morphological characters were scored for 44 exemplars, including six outgroup, two xyelic tenthredinoid, five pamphilioid, three cephoid, five ‘siricoid’, one orussid, and six apocritan taxa. The datas analysed with parsimony under equal weights and under implied weights. The monophyly of the Hymenopte strongly supported but the sistergroup of the Hymenoptera cannot be identified with confidence. The relations of the ‘symphytan’ lineages are Xyeloidea +(Tenthredinoidea+ (Pamphilioidea + (Cephoidea + (Ariaxyelic (Siricidae + (Xiphydriidae +(Orussoidea+Apocrita))))))). Many of the relationships between the superfamilies, especially in the basal branching pattern, are only weakly corroborated. The monophyly of most superfamilies is supported, and all may be monophyletic except the ‘Siricoidea’, which is clearly paraphyletic. It is difficult to di whether the Siricidae or the Anaxyelidae are the closest relatives of Xiphydriidae + (Orussoidea + Apocrita). support for the sistergroup relationship between the Orussoidea and the Apocrita is substantial, putative apomorphies being provided by most character systems. There is also good evidence in favour of the monophj the Apocrita. The internal phylogeny of the Tenthredinoidea differs considerably from the results of earlier anal The Blasticotomidae are the sistergroup of the Tenthredinoidea s.s. Relationships at the base of the Tenthredini s.s. are weakly supported. It is uncertain whether the Tenthredinidae are monophyletic or comprise a 1 paraphyletic grade within the Tenthredinoidea s.s. The Diprionidae may be the sistergroup to Cimbicidae +(Argidae+ Pergidae). Most relationships within the Cimbicidae + (Argidae + Pergidae) clade are corroborated, with the exception of the monophyly of the Argidae. It is proposed to elevate the Anaxyelidae the Xiphydriida both to superfamily status. The family‐level classification of the Tenthredinoidea will probably have to be changed, but this must await further clarification of the phylogeny of this superfamily.     

Host plant, oviposition behavior and larval ecology of a sawfly leafminer, Profenusa japonica (Hymenoptera: Tenthredinidae)

The host plant, oviposition behavior and larval ecology of Profenusa japonica Togashi are reported for the first time. Adults of P. japonica mated and oviposited on a polyantha rose, Rosa multiflora (Rosaceae), in April. Each female adult laid an egg on the edge of a leaflet. Hatched larvae consumed the parenchymatous layer of leaflets and in so doing created a mine. The larval stage comprised five instars. On average, 70.6% of the total area of a leaflet was consumed by one larva. Female adults of P. japonica laid eggs singly, probably to avoid larval competition for food.     

A comparison of nest construction behavior in two species ofPolistes paper wasps (Insecta,Hymenoptera: Vespidae)

Polistes fuscatus variatus (a north temperate wasp) andP. instabilis (a tropical wasp) begin building their nests by applying pulp in a linear sequence of steps: surface preparation, petiole, flat sheet, first cell. After the initiation of first cell there are multiple locations for pulp addition (petiole, new cell, old cell), which become increasingly varied inP. fuscatus as the nest grows (secondary petioles, comb back, substrate, and pupal caps). AlthoughP. fuscatus also adds oral secretion to the petiole, comb back, and pupal caps,P. instabilis only applies oral secretion and no pulp to these locations and does not build secondary petioles or place pulp on the substrate. Both species show a similar series of behavioral acts leading from pulp foraging to application. In both species queens initiate more cells than do subordinates; nonetheless, subordinates account for a large percentage of initiated cells. During pre-emergence and early post-emergence the majority of pulp is used for cell lengthening. BothP. instabilis andP. fuscatus show a bimodal pattern of growth in cell number. The numbers of cells in a mature comb at the end of the nesting cycle are similar in both species (P.f.=274.4 andP.i.=282.6 cells).     

Mitochondrial DNA phylogeography of the Cotesia flavipes complex of parasitic wasps (Hymenoptera: Braconidae)

The Cotesia flavipes species complex of parasitic wasps are economically important worldwide for the biological control of lepidopteran stem borers. The complex currently comprises three species: Cotesia flavipes Cameron, C. sesamiae (Cameron) and C. chilonis (Matsumura) (Hymenoptera: Braconidae), which appear morphologically similar. Despite their economic importance, little is known about the genetic diversity and phylogeography of these parasitoids. Differences in the biology of geographic populations have generally been interpreted as genetic divergence among strains, but direct genetic evidence is lacking. In Australia, several stem borer pests in neighbouring countries have been identified as significant threats to the sugar industry. However, the status of C. flavipes in Australia is unknown. To examine the genetic variation among worldwide populations of the C. flavipes complex and investigate the status of the Australian C. flavipes-like species, partial sequence data were generated for mitochondrial gene regions, 16S rRNA and COI. Parsimony, minimum evolution and Bayesian analyses based on 21 geographic populations of the complex and four outgroups supported the monophyly of the complex and the existence of genetically divergent populations of C. flavipes and C. sesamiae. The geographically isolated Australian haplotypes formed a distinct lineage within the complex and were ~3.0% divergent from the other species. The results indicated that historical biogeographic barriers and recent biological control introductions play an important role in structuring lineages within these species. This study provides a phylogeographical context for examining adaptive evolution and host range within biologically divergent strains of the C. flavipes complex.     

Comparative morphology of the venom gland and reservoir in opiine and alysiine braconid wasps (Insecta, Hymenoptera, Braconidae)

Detailed venom reservoir and venom gland intima morphology was investigated in representatives of 178 species and 76 genera of Braconidae belonging to the subfamilies Opiinae (23 genera and 69 species) and Alysiinae (36 genera and 67 species of Alysiini, and 17 genera and 42 species of Dacnusini). The presence of an unsculptured sack–like expansion of the anterior end of the reservoir suggests a relationship between some members of the alysiine tribe Dacnusini, viz. Exotela and Chorebus , and the genera Oenonogaster and Glyphogaster , both of which are currently placed in the Alysiini. The same feature also suggests that Exotela, Chorebus, Oenonogaster and Glyphogaster may be derived from the Opiinae separately from other Alysiinae. Other dacnusines examined are indicated as forming a monophyletic taxon on the basis of their reduced and narrow reservoirs. An anterior insertion of the venom glands on to the reservoir generally supports the Phaenocarpa group of alysiine genera, with some modification, whereas the presence of a discrete, narrow posterior extension of the reservoir represents a synapomorphy for members of the Aspilota group of alysiine genera. The phylogenetic inferences from this venom apparatus study are discussed in the light of the biology of the taxa concerned. Twenty-one new combinations are made in the Opiinae and seven in the Alysiinae.     

Revision of the Australasian genus Orussobaius Benson (Hymenoptera: Symphyta: Orussidae)

Abstract The Australasian genus Orussobaius Benson is revised. Seven species are recognised: Orussobaius paniculus sp. n. from Papua New Guinea, and six species from Australia: O. badius sp. n., O. caligneus sp. n., O. mesembrinus Benson, O. minutissimus sp. n., O. minutus Benson, and O. wilsoni Benson. Orussobaius normani Rayment (new synonymy) is removed from synonymy with O. wilsoni and treated as a junior synonym of O. minutus instead. With a body length of only 2 mm, O. minutissimus sp. n. is the smallest currently known sawfly species in the world. A key is provided and distribution maps are shown for all species. The genus Orussobaius is redefined on the basis of all species currently included.