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Mating in ants often occurs on the wing during nuptial flights or on the ground when scattered female sexuals attract males by pheromones. In both scenarios, there is little opportunity for males to engage in prolonged aggressive competition or elaborate courtship displays. Male morphology is therefore adapted to locating female sexuals and mating, and it lacks specific weapons or other traits associated with courtship. In contrast, sexuals of the ant genus Cardiocondyla typically mate in their natal nests. As a consequence, in many species winged males have been replaced by wingless fighter or territorial males, which kill or expel rival males with their strong mandibles and show complex mating behavior. However, no wingless males are known from Cardiocondyla zoserka from West Africa, and instead, winged males have evolved a bizarre secondary sexual trait: uniquely shaped antennae with spoon‐like tips that show heavily sculptured ventral surfaces with numerous invaginations. We here report on the courtship behavior of C. zoserka males and describe antennal glands with class 3 gland cells, which presumably secrete a close range sex pheromone. Antennal glands have not yet been found in males of other ant species, including a close relative of C. zoserka, suggesting that in ants with intranidal mating sexual selection can rapidly lead to highly divergent adaptations and the evolution of novel structures.

The ant genus Cardiocondyla is characterised by a remarkable variability of reproductive life histories and colony structures. Little is known about the C. stambuloffii group, whose distribution ex...

A new species of aphid, Xerobion eteriae sp. n., is described based on apterous and alate viviparous females, living on Acantholimon (Plumbaginaceae) in Iran. Differences from the most similar spec...

Apterous viviparous females of Macrosiphum dzhibladzeae Barjadze sp. n. living on Euphorbia macroceras (Euphorbiaceae) are described and illustrated. A key to the apterous viviparous females of Macrosiphum species living on Euphorbia spp. worldwide is given. A previous key for the apterous viviparous females of the Macrosiphum species recorded from Transcaucasia is provided, modified to include the new species.

SummaryThe hitherto unknown oviparous females and alate males of M. dzhibladzeae Barjadze, 2010, living on Euphorbia macroceras Fish. & Mey. and Euphorbia sp. (Euphorbiaceae), are described from re...

1. Bergmann's rule states that organisms inhabiting colder environments show an increase in body size or mass in comparison to their conspecifics living in warmer climates. Although originally proposed for homoeothermic vertebrates, this rule was later extended to ectotherms. In social insects, only a few studies have tested this rule and the results were ambiguous. Here, ‘body size’ can be considered at two different levels (the size of the individual workers or the size of the colony). 2. In this study, data from 53 nests collected along altitudinal gradients in the Alps were used to test the hypotheses that the worker body size and colony size of the ant Leptothorax acervorum increase with increasing altitude and therefore follow Bergmann's rule. 3. The results show that the body size of workers but not the colony size increases with altitude. Whether this pattern is driven by starvation resistance or other mechanisms remains to be investigated.

At present the biological control as a pest control technology is becoming more desirable. Biological formulations on basis of entomopathogenic nematodes are one of the effective means for the protection of agricultural and forest plants from harmful insects. Nowadays, the use of entomopathogenic nematodes as biological control agents is a key component in IPM system. The foraging strategies of entomopathogenic nematodes (EPNs) vary between species. This variation is consistent with use of different foraging strategies between ambush, cruise and intermediate to find their host insects. In order to ambush prey, some species of EPNs nictate, or raise their bodies of the soil surface so they are better poised to attach passing insects, other species adopt a cruising strategy and rarely nictate. Some species adopt an intermediate strategy between ambush and cruise. We compared in laboratory the foraging strategies of the entomopathogenic nematode species: Steinernema carpocapsae, Heterorhabditis bacteriophora and the recently described species Steinernema tbilisiensis and assessed their virulence against mealworm beetle, Tenebrio molitor L. (Coleoptera: Tenebrionidae). The tests showed that S. tbilisiensis adopts both foraging strategies.

Animal societies vary considerably concerning how reproductive rights are partitioned among individual group members (“reproductive skew”). Nestmate queens of most polygynous species contribute more or less equally to the brood, but queens of a few species of the genus Leptothorax form dominance hierarchies in which only the top ranking queen lays eggs (“functional monogyny”). As predicted by optimal skew models, high skew appears to be associated with habitat patchiness. Here, we document functional monogyny in the Caucaso-Anatolian ant Leptothorax scamni (Ruzsky 1905). Similar to related species, young female sexuals mate on the ground near their natal nests and thereafter either disperse to found new colonies solitarily or in groups or return into their natal nest, where only one of several co-occurring queens reproduces. A phylogeny of Leptothorax species based on partial CO I sequences corroborates the view that functional monogyny has evolved convergently in several taxa of Leptothorax. It thus is a relatively labile trait that can rapidly adapt to habitat changes.

A small minority of the presently recognized ∼12,500 species of ants are slave-makers, which permanently depend on the help of “slave workers,” that is workers of other ant species, which they pillage as brood from their nests in well-organized slave raids. The genus Myrmoxenus is one of the most species-rich taxa of slave-making ants, but individual species are often not well-delimited. Here, we compare behavior, morphometry, and nuclear and mtDNA sequences between two taxa of Myrmoxenus: Myrmoxenus tamarae (Arnoldi, 1968), known only from its type locality in Georgia, and the wide-spread M. ravouxi (Andre, 1896) to determine if the former might simply represent a Caucasian variant of the latter. Workers of the two taxa differed clearly in locomotor activity and slightly also in morphometry, while genetic investigations with nuclear and mitochondrial genes revealed only a weak differentiation. Given that Myrmoxenus appears to be a genus with a relatively recent radiation, we suggest to conservatively keep the present taxonomic situation with M. ravouxi and M. tamarae as separate species. The latter would then include specimens from Eastern Turkey and probably also Ukraine. Further studies, in particular in Greece and Turkey, might help to clarify the status of these endangered ants.

Fundatrices of Zelkovaphis caucasica (Dzhibladze 1960) are described and illustrated. A key to the fundatrices of the genus Zelkovaphis species is given. A transfer experiment was carried out to establish the life cycle of Z. caucasica. In addition, the life cycle of this species was studied in field conditions. The secondary host plant was established as Carex capitata.

43 aphid species, living on 39 host plants, were recorded from the Ajameti reserve (Georgia) in 2008. Two species (Aphis rubiae Narzikulov, 1964 and A. violae Schouteden, 1900) were recorded for the first time from Transcaucasia, while fourteen species were new records for Imereti Region. Fundatrices of Macrosiphum symphyti Barjadze et Chakvetadze, 2008 were found for the first time. Tritrophic relationships between aphids, their natural enemies and host plants were studied

Alate viviparous females of Wahlgreniella nervata (Gillette) were found on a Damask rose (Rosa damascena Mill.) plantation in Isparta Province, Turkey. The aphid is recorded for the first time from Turkey. Besides, Damask rose is a new host for this species. Brief information about this aphid including a key to the alate females of aphid species known to infest Damask rose in Turkey is provided.

Aphidius eglanteriae as a parasitoid of Chaetosiphon tetrarhodum/ Rosa is newly recorded for Turkey. Short information about its parasitism rate and distribution in Isparta Province, Turkey, is given. A nother new information pertains to the association between Aphidius matricariae - Aphis illinoisensis - Vitis vinifera.