Gary A. P. Gibson

Phylogenetics and classification of Chalcidoidea and Mymarommatoidea — a review of current concepts (Hymenoptera, Apocrita)

Classification and morphological and molecular evidence supporting relationships of Mymarommatidae (Mymarommatoidea) and the 20 families of Chalcidoidea are reviewed. Five autapomorphies support monophyly of Mymarommatoidea, at least two autapomorphies support monophyly of Chalcidoidea, and three synapomorphies support a sister‐group relationship between Mymarommatoidea and Chalcidoidea. Mymaridae are indicated as the likely sister group of all other Chalcidoidea by: two features of the ovipositor, the unique structure of a muscle between the mesofurca and axillary lever, and sequence data from the 28s rDNA gene. Structure of the upper valvulae of the ovipositor could indicate Rotoitidae as the second‐most basal clade of Chalcidoidea. Chalcididae, Elasmidae, Encyrtidae, Eulophidae, Eurytomidae, Leucospidae, Mymaridae, Ormyridae, Rotoitidae, Signiphoridae, Torymidae and Trichogrammatidae are each indicated as monophyletic by at least one putative synapomorphy, but could render other families paraphyletic. Aphelinidae, Eupelmidae, Pteromalidae, and Tetracampidae are not demonstrably monophyletic. Agaonidae is monophyletic only if restricted to Agaoninae, and Eucharitidae is monophyletic only if restricted to Eucharitinae + Oraseminae. Eupelmidae may be paraphyletic with respect to Tanaostigmatidae and Encyrtidae, and Tanaostigmatidae including Cynipencyrtus may be paraphyletic relative to Encyrtidae. Perilampidae (Perilampinae + Chrysolampinae) are either polyphyletic or paraphyletic with respect to Eucharitidae + Akapalinae + Philomidinae. No cladistic hypotheses of familial relationships based on character evidence have considered the superfamily in its entirety.

Sister‐group relationships of the Platygastroidea and Chalcidoidea (Hymenoptera) — an alternate hypothesis to Rasnitsyn (1988)

Evidence for the hypothesis that Platygastroidea and (Chalcidoidea + Mymarommatoidea) are sister groups is reviewed and an alternate hypothesis of relationships is proposed for Platygastroidea. Platygastroidea is postulated to form a monophyletic group with Pelecinidae, Proctotrupoidea and Vanhorniidae based on common possession of an annular pronotum and a mesopleural‐mesotrochanteral muscle. Hypotheses of character‐state transformation are illustrated diagrammatically to explain distribution of the mesotrochanteral depressor muscle and relative structure of the pronotum, mesothoracic spiracle, prepectus, and pronotal‐mesepisternal attachment throughout the nonaculeate Apocrita. The states of 16 characters are defined in one table and another table summarises the distribution of the states in Orussidae and Apocrita. Retention of an independent prepectus and a mesotergal‐mesotrochanteral depressor muscle indicates that Chalcidoidea + Mymarommatoidea are a relatively early clade of Apocrita but does not indicate exact relationships. Chalcidoidea + Mymarommatoidea are indicated as possibly being more closely related to Diapriidae or Ceraphronoidea based on other characters. It is postulated that structure of the mesocoxal articulation of taxa assigned to the Evaniomorpha may represent a retained symplesiomorphy rather than a synapomorphy. Mesocoxal articulatory structure is illustrated by scanning electron photomicrographs.

An integrative approach to species discrimination in the Eupelmus urozonus complex (Hymenoptera, Eupelmidae), with the description of 11 new species from the Western Palaearctic

The systematics of the European species of Eupelmus (Eupelmus) Dalman (Hymenoptera: Eupelmidae) belonging to the ‘urozonus‐complex’ is elucidated through combined molecular and morphological characterization. One mitochondrial gene fragment (Cytochrome oxidase I) and one nuclear protein‐coding gene fragment (Wingless) were sequenced and the results compared with those of a detailed morphological study of the specimens from an extensive sampling. Knowledge of the biodiversity of Eupelmus in the Western Palearctic Region is significantly improved through the separation and description of 11 new species: E. (Eupelmus) confusus Al khatib sp.n., E. gemellus Al khatib sp.n., E. janstai Delvare & Gibson sp.n., E. longicalvus Al khatib & Fusu sp.n., E. minozonus Delvare sp.n., E. opacus Delvare sp.n., E. pistaciae Al khatib sp.n., E. priotoni Delvare sp.n., E. purpuricollis Fusu & Al khatib sp.n., E. simizonus Al khatib sp.n. and E. tremulae Delvare sp.n. Illustrated keys to females and, when known, males of these new 11 species plus the other already described species considered to belong to the ‘urozonus‐complex’ (E. acinellus Askew, E. annulatus Nees, E. azureus Ratzeburg, E. cerris Förster, E. fulvipes Förster, E. kiefferi De Stefani, E. martellii Masi, E. stenozonus Askew, E. tibicinis Bouček and E. urozonus Dalman) are provided and all the species are described based on morphology. Eupelmus kiefferi is removed from synonymy under E. urozonus and E. azureus is recognized as the valid senior synonym of Pteromalus cordairii Ratzeburg, and Eupelmus spongipartus Förster, syn.n. The discrimination of the species included in this complex is particularly relevant because some are potential biological control agents and have been confused in the past.

The spatio-temporal distribution dynamics of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Coleoptera: Curculionidae), and its larval parasitoids in canola in western Canada

Abstract Distribution patterns of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), and its larval parasitoids were investigated in commercial fields of spring canola (Brassica rapa L. and Brassica napus L.) in southern Alberta, Canada, from 2002 to 2004 in relation to developmental stages of its host plants. Adult weevils invaded fields along one or more fronts when crops were in bud to early flower. Significant clustering of adults along field edges in early stages of invasion was followed by more homogeneous distributions as canola reached the mid to late flowering and pod enlargement stages. Larval weevil distributions, as indicated by exit holes in siliques at the end of the season, were often aligned spatially with adult distributions, but they did not coincide in all regions of the fields. The primary ectoparasitoid species attacking weevil larvae comprised Necremnus tidius (Walker) (Hymenoptera: Eulophidae), and Trichomalus lucidus (Walker), Chlorocytus sp., and Pteromalus sp. (Hymenoptera: Pteromalidae). Parasitism rates increased from 0.1 to 5.0% over the three years of study. Parasitoid distributions were often, but not consistently, spatially associated with high densities of C. obstrictus larvae. Lack of close spatial alignment of parasitoids and their hosts probably reflects low parasitoid numbers in comparison with an abundant resource of weevil larvae, and a lack of co-evolutionary history between host and parasitoids. Some parasitoids invaded fields early in host plant development, at the same time that weevils invaded. Unfortunately the synchronous invasions of host and parasitoids indicate that insecticidal applications to reduce adult weevil infestations may be detrimental to these beneficial species.

Importance of long-term research in classical biological control: an analytical review of a release against the cabbage seedpod weevil in North America

Abstract:  Cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Col., Curculionidae), is an invasive alien pest that is spreading in North America. To aid with planning for introductions of European parasitoids in North America, we examined the status of the only classical biological control release against this pest in North America, which in 1949 introduced Mesopolobus morys, Stenomalina gracilis and Trichomalus perfectus (Hym., Pteromalidae). Weevils and parasitoids were reared in 2005 from mass collections of seedpods of Brassica napus, Brassica rapa and Raphanus raphanistrum (Brassicaceae) from 18 sites in the Fraser Valley, near Vancouver, British Columbia, Canada. Of the three European parasitoid species that were originally released, only S. gracilis was found. The predominant hymenopterous parasitoid species were Trichomalus lucidus, S. gracilis, Mesopolobus moryoides (Pteromalidae), Necremnus tidius (Eulophidae) and Eupelmus vesicularis (Eupelmidae). These constituted over 97% of the parasitoids reared, although overall parasitism was low. Only M. moryoides is clearly North American in distribution; other than S. gracilis, the remaining species were either accidentally introduced or are Holarctic in distribution. Based on these results, re‐releases of M. morys and T. perfectus in North America should be considered as part of a classical biological control programme. However, redistribution of S. gracilis is not recommended at present because of potential conflicts with biological control programmes against weeds. Ongoing re‐examination of classical biological control programmes can further our understanding of failure of release programmes, particularly when re‐examination can be made in the light of improved taxonomy and systematics of the target and agent species.

Responses of Chalcidoidea (Hymenoptera) parasitoids to invasion of the cabbage seedpod weevil (Coleoptera: Curculionidae) in western Canada

Invasion of the European weevil, Ceutorhynchus obstrictus (Marsham), was investigated through surveys of its range and population densities in Alberta and Saskatchewan from 2001 to 2005. After it was first reported in southern Alberta, C. obstrictus rapidly expanded its range and abundance. Our more recent surveys indicate that its northward expansion has slowed, but that it has continued to extend its range eastward to southcentral Saskatchewan. The distribution and abundance of parasitoids of C. obstrictus in Alberta and Saskatchewan were investigated from 2003 to 2005 by mass rearing canola pods infested with C. obstrictus larvae. Although weevil populations were not parasitized for several years immediately following its introduction to southern Alberta, a surprisingly diverse assemblage of Chalcidoidea parasitoids, comprising 12 species from four families, were recently reared from weevil-infested canola siliques in Alberta and Saskatchewan. The Chalcidoidea fauna of C. obstrictus include species with both Nearctic and Holarctic distributions, with some species having restricted host ranges and others that are more niche than taxon-specific. These Chalcidoidea species appear to have expanded their host ranges to parasitize C. obstrictus in the region. Most parasitism is attributable to Trichomalus lucidus (Walker), Chlorocytus sp., and Pteromalus sp. (Pteromalidae), and Necremnus tidius (Walker) (Eulophidae). Parasitism levels varied considerably over the three years of this study. From 2003 to 2005 increases in parasitism occurred among all four of the species dominating the parasitoid fauna of C. obstrictus, but greater increases were observed for Chlorocytus sp. and Pteromalus sp. than for T. lucidus. Parasitoid species have sometimes caused substantial levels of host mortality, although current levels are usually less than 15% for all species combined and so are not sufficient to control weevil populations. Implementing a classical biological control program for C. obstrictus by reconstructing its European natural enemy complex is being considered, but it is still uncertain whether parasitism levels by native Chalcidoidea will increase over time since considerable year-to-year variation has been found. Parasitism levels of C. obstrictus should therefore continue to be monitored to assess whether a classical biological control program should be implemented.

Review of the family Rotoitidae (Hymenoptera: Chalcidoidea), with description of a new genus and species from Chile

A new genus and species of Rotoitidae, Chiloe micropteron Gibson and Huber, is described from females and one male from Chile. The taxon is the second known genus and species, and the male is the only one known for the family. Scanning electron micrographs illustrate external and internal structure of C. micropteron females, and external structure of Rotoita basalis

Revision of the Palaearctic species of Eupelmus (Eupelmus) Dalman (Hymenoptera: Chalcidoidea: Eupelmidae).

One hundred-four extant species of Eupelmus Dalman (Hymenoptera: Eupelmidae: Eupelminae) are recognized from the Palaearctic region, of which 76 species of E. (Eupelmus) are recognized following a revision of the Palaearctic fauna of the subgenus. The following 25 species are described as new: E. (Eupelmus) adustus Gibson & Fusu n. sp., E. (Eupelmus) angustifrons Gibson & Fusu n. sp., E. (Eupelmus) bicolor Gibson & Fusu n. sp., E. (Eupelmus) brachypterus Fusu & Gibson n. sp., E. (Eupelmus) brachystylus Gibson & Fusu n. sp., E. (Eupelmus) brachyurus Fusu & Gibson n. sp., E. (Eupelmus) fasciatus Gibson & Fusu n. sp., E. (Eupelmus) gelechiphagus Gibson & Fusu n. sp., E. (Eupelmus) hayei Gibson & Fusu n. sp., E. (Eupelmus) infimbriatus Gibson & Fusu n. sp., E. (Eupelmus) iris Fusu & Gibson n. sp., E. (Eupelmus) kamijoi Gibson & Fusu n. sp., E. (Eupelmus) lanceolatus Gibson & Fusu n. sp., E. (Eupelmus) luteipes Fusu & Gibson n. sp., E. (Eupelmus) magdalenae Fusu & Gibson n. sp., E. (Eupelmus) mehrnejadi Gibson & Fusu n. sp., E. (Eupelmus) melanostylus Gibson & Fusu n. sp., E. (Eupelmus) punctatifrons Fusu & Gibson n. sp., E. (Eupelmus) setosus Fusu & Gibson n. sp., E. (Eupelmus) tanystylus Gibson & Fusu n. sp., E. (Eupelmus) tetrazostus Gibson & Fusu n. sp., E. (Eupelmus) vanharteni Fusu & Gibson n. sp., E. (Eupelmus) weilli Fusu & Gibson n. sp., E. (Eupelmus) xenium Fusu & Gibson n. sp., and E. (Eupelmus) zebra Fusu & Gibson n. sp. Of previously described species of Eupelmus, 17 are newly assigned to E. (Eupelmus), 10 to E. (Episolindelia Girault), and 8 to E. (Macroneura Walker). Formally transferred to E. (Macroneura) from Macroneura are E. (M.) algiricus (Kalina 1981), E. (M.) coleophorae (Kalina 1981), E. (M.) impennis (Nikolskaya 1952), E. (M.) longicornis (Kalina 1981), E. (M.) pleuratus (Kalina 1981) and E. (M.) sugonyaevi (Kalina 1981) n. combs. Eupelmus (Eupelmus) kalinai Gibson & Fusu n. name is given to replace E. (Eupelmus) algiricus Kalina 1988, a secondary homonym of E. (M.) algiricus (Kalina 1981). New synonyms proposed are Eupelmus scolyti Liao 1987 n. syn. under E. (Eupelmus) formosae Ashmead 1904, and Eupelmus nigricauda Nikolskaya 1952 n. syn. under E. (Eupelmus) microzonus Förster 1860. Eupelmus gueneei Giraud 1870 and Eupelmus xambeui Giard 1900 are transferred to Arachnophaga (Parasolindenia Brues) as A. (P.) gueneei (Giraud) and A. (P.) xambeui (Giard) n. combs., and Eupelmus kim Nikolskaya 1952 is transferred to Brasema Cameron as B. kim (Nikolskaya) n. comb. Eupelmus puparum Newport 1840 is transferred to Pteromalus Swederus (Pteromalidae) as P. puparum (Newport) n. comb., a secondary homonym of P. puparum (Linnaeus 1758), and Ceraphron brachynterae Schwägrichen 1835 is removed from Eupelmus and Eupelmidae, and the name treated as incertae sedis. Lectotypes are designated for Eupelmus azureus Ratzeburg 1844, Pteromalus cordairii Ratzeburg 1844, Eupelmus hostilis Förster 1860, and Eupelmus splendens Giraud 1872. Neotypes are designated for Pteromalus audouinii Ratzeburg 1844 and Eupelmus bedeguaris Ratzeburg 1852. Newly recorded from the Palaearctic are E. (Eupelmus) orthopterae (Risbec 1951) and E. (Eupelmus) peculiaris Narendran (2011). Excluded from the Palaearctic are E. (Eupelmus) afer Silvestri 1914 (Afrotropical) and E. (Eupelmus) longicorpus (Girault 1915) (Australasian), the former being compared to E. confusus Al khatib 2015 and the latter to E. iranicus Kalina 1988 and E. kalinai. Seven informal species groups are recognized for the purpose of species comparisons, the fulgens-, fulvipes-, iranicus-, orientalis-, splendens-, stramineipes-, and urozonus-groups. The latter group is restricted to E. urozonus Dalman and five other species that were differentiated initially using molecular evidence. Females of all 76 species of E. (Eupelmus) recognized from the Palaearctic are keyed, described and illustrated. Males are recognized for 44 of the species, and keyed and illustrated, though not all males of the fulvipes- and urozonus-groups are distinguished from each other.

Contributions to the Life History, Host Range, and Distribution of Necremnus tidius (Hymenoptera: Eulophidae)

Abstract Field and laboratory studies investigated the preimaginal developmental time, adult emergence phenology, mating behavior, and weevil hosts of Necremnus tidius (Walker) (Hymenoptera: Eulophidae), a solitary ectoparasitoid of coleopteran larvae. In addition, changes in parasitism levels of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), by N. tidius were determined during 2003–2005 in commercial fields of canola (Brassica rapa L. and Brassica napus L.) in southern Alberta and Saskatchewan, Canada. Mean ± SE developmental time from egg to adult was 18.3 ± 0.23 d for specimens reared at 21°C and a photoperiod of 12:12 (L:D) h. Emergence began in late July in commercial fields near Lethbridge, AB, and 20 d later 81% of the population had emerged. Emergence was completed by the end of August. Mating was preceded by a complex courtship behavior with the male standing on the dorsum of the mesosoma and gaster of the female, flapping its wings without flight, leaning forward and stroking its antennae over the antennae of the female, leaning back, and repeating the sequence several times. The native weevil Ceutorhynchus neglectus Blatchley was determined to be an alternate host of N. tidius in central and northern Alberta. N. tidius was found in few commercial canola fields in 2003, but in 2004, it occurred over hundreds of thousands of hectares of canola cropland, reaching peak parasitism levels of 45%. In 2005, N. tidius was still common, but parasitism declined relative to that observed in 2004.

SYNOPSIS OF AUSTRALIAN CALYMMOCHILUS MASI (HYMENOPTERA: EUPELMIDAE), DESCRIPTION OF A NEW WESTERN AUSTRALIAN SPECIES ASSOCIATED WITH A PSEUDOSCORPION, AND REVIEW OF PSEUDOSCORPION PARASITES

The recognised Australian species of the eupelmid genus Calymmochilus Masi are reviewed. Diagnoses are presented for all described species and notes provided on eight potential new species, which are not named due to a lack of material and matched sexes. Calymmochilus longbottomi Gibson from Western Australia, reared from the pseudoscorpion Synsphyronus lathrius Harvey, is described as new, and Eupelmus longifasciatipennis Girault is transferred to Calymmochilus as a result of the previous synonymy of Tasmanastatus Boucek. Information is presented on morphological variation within and between species, their distribution and relationships, as well as a key to all known species, including those which are as yet unnamed. The occurrence of pseudoscorpion parasites (Hymenoptera, Acari and Nematoda) is reviewed, the record of C. longbottomi being highlighted as the first report of a chalcidoid associated with a pseudoscorpion.