Hasan Hüseyin Başıbüyük

Host location and oviposition in a basal group of parasitic wasps: the subgenual organ, ovipositor apparatus and associated structures in the Orussidae (Hymenoptera, Insecta)

Abstract Anatomical studies and behavioural observations indicate that representatives of the Orussidae use vibrational sounding to detect suitable oviposition sites. During host location, vibrations generated by tapping the tips of the antennae against the wood are picked up by the fore legs through the basitarsal spurs, transmitted along the basitarsi to thin-walled areas on the tibiae and through haemolymph to the subgenual organs, where they are transduced into nerve impulses. The apical antennomeres are distinctly shaped and have the cuticle thickened distally. The fore basitarsi have weakly sclerotised basitarsal lines proximally and membranous basitarsal spurs distally. The external wall of the fore tibiae have thin-walled areas distally on their posterior parts. Internally, large subgenual organs are situated opposite the thin-walled areas and each organ consists of 300–400 scolopidial units suspended between a lateral cuticular spine, a ventral sheet and a median ridge. The ovipositor is several times the length of the body of the wasp. When at rest, it extends all the way into the prothorax, where it is coiled before extending posteriorly to lie between the third valvulae distally. The ovipositor lies in a membranous ovipositor sac attached posteriorly to the proximal parts of the ovipositor apparatus and the posterior margin of sternum 7. In the ovipositor apparatus, the anterior parts of the second valvifers are displaced and expanded anterodorsally, inverting the first valvifers and the base of the ovipositor. When in use, the ovipositor is extended and retracted by median apodemes situated on the anterior margins of abdominal sterna 3–7. Longitudinal muscles between the apodemes allow the latter to grip the ovipositor in troughs between them. The ovipositor extends from the abdomen at the tip of sternum 7, and an internal trough on sternum 7 serves to guide the ovipositor into the wood. Despite the alterations observed in the ovipositor apparatus in the Orussidae, the musculature is almost complete and the mode of operation presumably not much different from that of other representatives of the Hymenoptera. The different ways parasitic wasps with very long ovipositors handle and accommodate these and the implications for the evolutionary history of Hymenoptera are discussed.

The limits of the family Evaniidae (Insecta: Hymenoptera) and a new genus from Lebanese Amberamber

The definition of the family Evaniidae is revised and Cretevaniidae are synonymised with Evaniidae based on evidence derived from recently described Mesozoic taxa and a new genus and species, Lebanevania azari, described here from Lebanese amber. A fore leg with a long trochanter and a 12-segmented antenna are autapomorphies of the new genus. A large, high and wide head and a high and short mesosoma are derived characters shared with other Evaniidae. The new genus also has complete fore wing venation and lacks a tubular petiole, which are ground plan features of the Evanioidea. A cladistic analysis of fossil and extant members of the superfamily Evanioidea and notes on fossil taxa are presented.

A basal chalcidoid (Insecta: Hymenoptera) from the earliest Cretaceous or latest Jurassic of Mongolia

Khutelchalcis gobiensis gen. et sp. n. (Khutelchalcididae fam. n.), based on a tiny impression fossil collected from the lowermost Cretaceous or uppermost Jurassic deposits of Khutel-Khara in East Mongolia, was studied using an environmental chamber scanning electron microscope. Character analysis suggests that the fossil belongs to a putative basal group of the Chalcidoidea. The greatly reduced wing venation, apparent presence of multiporous plate sensillae with long aperture on the flagellomeres, and a high antennal insertion all suggest that the new taxa is related to the Chalcidoidea. The angulation of fore wing vein Cu at the M+Cu fork is similar to that of Jurassic Jurapriidae, Cretaceous Serphitidae as well as various chalcidoids. This character might be a synapomorphy for Chalcidoidea + Serphitoidea (including Mymarommatidae) + Jurapriidae, which in turn are possibly a sister clade to Platygastroidea. The small size of this species is discussed in relation to conflicting scenarios concerning the plesiomorphic biology of the chalcidoid+proctotrupoid linage. Mymarommatidae and Serphitidae are combined in a single superfamily, Serphitoidea Brues, 1937 (= Mymarommatoidea Debauche, 1948, syn. nov.).

Two nearly complete mitogenomes of wheat stem borers, Cephus pygmeus (L.) and Cephus sareptanus Dovnar-Zapolskij (Hymenoptera: Cephidae): An unusual elongation of rrnS gene

Two nearly complete mitochondrial genomes (mitogenomes) of wheat stem borers, Cephus pygmeus and Cephus sareptanus (Hymenoptera: Cephidae), were sequenced, characterised and compared with the previously known mitogenome of Cephus cinctus. The gene orders are mostly conserved, except for translocation of trnM and swapped position of trnI and trnQ. An A+T bias was found, but a deviation from strand asymmetry was also detected on the J strand. All protein coding genes (PCGs) are initiated by ATN codons, except for nad1, nad2 and atp8, and all are terminated with TAA, TA- or T- as a stop codon. The predicted secondary structures of rrnS and rrnL genes are mostly consistent with reported hymenopteran species. However, an unusual elongation in rrnS, not know elsewhere in the order, was discovered in Cephus species. Three autonomous sequences detected in domains I and II are mainly responsible for the length expansions.

The complete mitogenomes of Calameuta filiformis (Eversmann, 1847) and Calameuta idolon (Rossi, 1794) (Hymenoptera: Cephidae): The remarkable features of the elongated A+T rich region in Cephini.

Two complete mitogenomes of the stem borers, Calameuta filiformis and Calameuta idolon, and the complete A+T-rich region of Trachelus iudaicus (Hymenoptera: Cephidae), are reported. The mitogenomes of these species are the longest reported from hymenopterans to date. A remarkable increase in length of the A+T-rich region, the longest for Hymenoptera, was found and compared across the tribe Cephini. The presence of the tRNA- and rRNA-like sequences were reported in the A+T-rich region of sawflies and they were suggested to play a role in replication and/or transcription. The long and short tandem repeats were orderly located in both sides of the A+T-rich region producing stable secondary structures. We suggest that the short tandem repeats are likely to function as a replication fork barrier.

Genetic Structure of Chorthippus parallelus (Orthoptera: Acrididae: Gomphocerinae) Populations in Anatolia: A Stable Rear Edge Population

ABSTRACT Anatolian populations inhabit the southern latitudinal margin of species distribution ranges and therefore may be considered as “rear edge” populations. The genetic structures of such populations have critical importance in species responses to climatic change and are essential for long-term conservation genetics. Here, the genetic structure of Chorthippus parallelus (Zetterstedt) (Orthoptera: Acrididae: Gomphocerinae) populations in one of the main southern glacial refugium is investigated. Ten populations of C. parallelus from Anatolia have been studied by investigating single-copy nuclear DNA (Cpnl-1) fragment using polymerase chain reaction-single strand conformational polymorphism methods. The level of allelic number was high (total of 20 alleles in the locus, of which 11 were unique), but the level of gene flow among populations seemed to be low (FIS = 0.090). However, most populations were genetically diverse (HE > 0.5, A = 6.211, and ne = 5.774). The level of genetic differentiation among populations was high (FST = 0.330). No statistically significant correlation between genetic diversity and spatial distribution was observed. The analysis of molecular variation analysis indicated that a large proportion of genetic variation was due to differentiation among individuals within populations. Genetic drift was a more likely cause of differentiation among populations rather than geographical distance. These results suggest that a presence of a “stable rear edge” population in contrary to the center-periphery model.

A molecular phylogeny of the Cephinae (Hymenoptera, Cephidae) based on mtDNA COI gene: a test of traditional classification

Abstract Cephinae is traditionally divided into three tribes and about 24 genera based on morphology and host utilization. There has been no study testing the monophyly of taxa under a strict phylogenetic criterion. A molecular phylogeny of Cephinae based on a total of 68 sequences of mtDNA COI gene, representing seven genera of Cephinae, is reconstructed to test the traditional limits and relationships of taxa. Monophyly of the traditional tribes is not supported. Monophyly of the genera are largely supported except for Pachycephus. A few host shift events are suggested based on phylogenetic relationships among taxa. These results indicate that a more robust phylogeny is required for a more plausible conclusion. We also report two species of Cephus for the first time from Turkey.