Miocene ants (Hymenoptera,Formicidae) from Crimea

Ant imprints, new and previously known, from Middle Miocene deposits near Kerch (Crimean Peninsula, Russia) are described or redescribed. A new Myrmicinae species, Solenopsis atavinus sp. nov., is described based on a wingless female. A winged female similar to the earlier described Dolichoderus tauricus Dlussky, 1981 is found: due to the excellent preservation of this specimen, the new specimen and the holotype of D. tauricus are redescribed and can be reclassified as Ponerites tauricus (Dlussky, 1981), comb. nov. Oecophylla taurica sp. nov. is described based on a partly preserved imprint of a female thorax with a forewing, the venation of which allows it to be positively identified as a weaver ant. Two other species are transferred from the formal genus Camponotites to Oecophylla based on forewing venation: O. kraussei (Dlussky et Rasnitsyn, 1999), comb. nov. (Early Eocene, United States) and O. macroptera (Dlussky, 1981), comb. nov. (Middle Miocene, Stavropol, Russia). One of the studied forewing imprints is similar in venation to Paraphaenogaster microphthalmus Dlussky, 1981, described from the Middle Miocene of Vishnevaya Balka (Stavropol province, Russia) and so is attributed to this species. Dolichoderus tavridus sp. nov. is described based on a forewing.     

Atypical vitellins in ponerine ants (Formicidae: Hymenoptera)

Higher hymenopteran vitellogenin/vitellins have been characterized as containing one large apoprotein. We show that in the ant subfamily Ponerinae, species in the tribes Odontomachini, Platythyrini, and Amblyoponini, also have a vitellin with this simple structure, containing a single apoprotein of 180-190kDa. Species in tribes Ponerini and Ectatommini, however, have vitellins containing multiple subunits. The size and number of the subunits varies, with differences even among species within the same genus. This is the first report of diversity in vitellogenin structure in the higher Hymenoptera. Vitellin and vitellogenin in Harpegnathos saltator (Ponerini) contain two large subunits of about 165kDa and two small subunits of about 45 and 43kDa. N-terminal sequence analysis suggests that provitellogenin is cleaved at two different sites, producing two large and two small subunits differing slightly in size. Diversity of vitellin types in Ponerini and Ectatommini is similar to that found in the more primitive tenthredinoid sawflies (Hymenoptera, Symphyta), and may indicate polyphyly in the Ponerinae. Insect vitellogenins and yolk proteins show considerably more diversity than originally believed, and the possibility of the functional significance of these differences should be considered.     

Karyological studies of Japanese ants (Hymenoptera,Formicidae)

The karyotypes of nine Japanese ants in three subfamilies (Ponerinae, Formicinae, and Myrmicinae) were successfully analysed by the improved squash technique. Three ponerine species had 2n=7 and n=4 (Ponera scabra), 2n=22 (Brachyponera sinensis), and 2n=28 and n=14 (Cryptopone sauteri). Four formicine species had 2n=18 and n=9 (Camponotus sp. and C. tokioensis), 2n=26 and n=13 (Camponotus japonicus), and 2n=30 and n=15 (Lasius niger). Two myrmicine species had 2n=18 and n=9 (Leptothorax congruus), and 2n=37, 38, 39, and n=17, 18, 19, 20 (Pheidole nodus). It was found that the variation of chromosome number observed in P. nodus was caused by Robertsonian type polymorphism.     

The internal phylogeny of ants (Hymenoptera: Formicidae)

Abstract. The higher phylogeny of the Formicidae was analysed using 68 characters and 19 taxa: the 14 currently recognized ant subfamilies plus 5 potentially critical infrasubfamilial taxa. The results justified the recognition of 3 additional subfamilies: Aenictogitoninae Ashmead (new status), Apomyrminae Dlussky & Fedoseeva (new status), and Leptanilloidinae Bolton (new subfamily). A second analysis on these better delimited 17 subfamilies resulted in 24 equally most parsimonious trees. All trees showed a basal division of extant Formicidae into two groups, the first containing (Myrmicinae, Pseudomyrmecinae, Nothomyrmeciinae, Myrmeciinae, Formicinae, Dolichoderinae, Aneuretinae) and the second the remaining subfamilies. Clades appearing within these groups included the Cerapachyinae plus 'army ants', the Nothomyrmeciinae plus Myrmeciinae, the 'formicoid' subfamilies (Aneuretinae + Dolichoderinae + Formicinae), and the Old World army ants (Aenictinae + Aenictogitoninae + Doryline), but relationships within the last two groups were not resolved, and the relative positions of the Apomyrminae, Leptanillinae and Ponerinae remained ambiguous. Moreover, a bootstrap analysis produced a consensus tree in which all branches were represented in proportions much lower than 95%. A reconstruction of the ground plan of the Formicidae indicated that the most specialized of all recent ants are the members of the subfamily Dorylinae and the least specialized ones are the monotypic Apomyrminae.     

Common names for Australian ants (Hymenoptera: Formicidae)

Abstract Most insects do not have common names, and this is a significant barrier to public interest in them, and to their study by non-specialists. This holds for even highly familiar insect groups such as ants. Here, I propose common names for all major native Australian ant genera and species-groups, as well as for many of the most abundant and distinctive species. Sixty-two genera, 142 species-groups and 50 species are given names. The naming system closely follows taxonomic structure; typically a genus is given a general common name, under which species-group and species names are nested.     

Catalogue of the ants (Hymenoptera, Formicidae) of Bulgaria

The present catalogue of the ants (Hymenoptera, Formicidae) of Bulgaria is made on a base of critical reconsideration of literature (covering the period from 1892 till 2009 and part of 2010) as well as on examination of the authors' and several museum's collections. A lot of data were omitted in the previous Bulgarian monograph on ants, lots of new data were recently added and many important additions and alterations were made due to taxonomic revisions of Eurasian Formicidae during the last three decades. Two new species are reported for the country [Temnothorax graecus (Forel, 1911) and Temnothorax cf. korbi (Emery, 1924)].This catalogue contains a list of 163 ant species belonging to 40 genera of 6 subfamilies now known from Bulgaria. Synonyms and information on the previously reported names in relevant publications are given. Known localities of the species are grouped by geographic regions. Maps with concrete localities or regions for each species were prepared. The conservation status of 13 ant species is given as they are included in IUCN Red List of Threatened Species and Bulgarian Biodiversity Act. In comparison with adjacent Balkan regions the ant fauna of Bulgaria is quite rich and its core is composed of South European elements.     

Seasonal changes in the canopy arthropod fauna in Rinorea beniensis in Budongo Forest,Uganda

Arthropods were collected by insecticidal tree fogging on the understorey tree species Rinorea beniensis Engler (Violaceae) in Budongo Forest, a seasonal rain forest in Uganda. Eight trees were fogged in adjacent plots of primary, selectively logged and swamp forest during the wet season and again in the dry season. In all forest types, Psocoptera, parasitoid Hymenoptera, and especially Formicidae and Auchenorrhyncha were more abundant during the dry season, while Ensifera, Heteroptera, Lepidoptera, Diptera, and Coleoptera were more abundant during the wet season. Seasonal change in arthropod composition was very low in the swamp forest located near a stream, where permanent water supply is crucial for the development of the distinct swamp vegetation, with comparatively constant microclimatic conditions all over the year. Seasonal change increased in the primary forest, and shows most significant changes of athropod abundance between dry and wet season in the selectively logged forest which also had the highest heterogeneity in forest structures. Especially small and soft bodied arthropods probably accumulate along a humidity gradient in the dense canopies of Rinorea during the dry season, when the forest floor outside the swamp forest is dry. This effect, which is also strongest in the selectively logged forest, leads to a much higher density of canopy dwelling arthropods during the dry season.     

Arboreal search in ants: Search on branches (Hymenoptera: Formicidae)

Ants (Formicidae) perform two distinct search behaviors for resources: on the ground they use irregular, almost random alternating looping, and on branches and leaves they resort to outline-tracing (arboreal systematic search), whereby the individual systematically turns to one side at bifurcations and to the opposite side when turning about at end points. Experiments with searching Formica pallidefulva and Crematogaster cerasion artificial stick mazes under seminatural conditions demonstrated that bifurcations and end points only trigger turn decisions, whereas an intrinsic mechanism specifies the handedness of such turns. Arboreal homing differs from arboreal searching by a much stronger tendency to rectify paths by counterturning. The theory is advanced that searching on branches by outline-tracing is evolutionarily derived from ranging search by superposing a sustained intrinsic turn bias and by suppressing random turns.     

Mitochondrial genome evolution in fire ants (Hymenoptera: Formicidae)

Background  

Complete mitochondrial genome sequences have become important tools for the study of genome architecture, phylogeny, and molecular evolution. Despite the rapid increase in available mitogenomes, the taxonomic sampling often poorly reflects phylogenetic diversity and is often also biased to represent deeper (family-level) evolutionary relationships.     

Further records of ants (Hymenoptera: Formicidae) from Iran

Wide ranging surveys of the ant fauna of Iran have enabled us to add a further 30 named species to the country list. A review of almost all the published literature and of photographs of unidentified specimens within the public domain gives a grand total of 248 species, from seven subfamilies and 37 genera. In the majority of instances, our own specimens were compared with type images available from antweb.com. This has led us to propose new or revised status for Cataglyphis turcomanica Crawley 1920, Lepisiota integrisquama (Kuznetsov-Ugamsky, 1929), Lepisiota surchanica (Kuznetsov-Ugamsky, 1929) and Messor obscurior Crawley 1920. We note that the total includes a number of what may be misidentifications and a small number of named species that seem unlikely to occur in Iran.     

Choice of food resource by bees and ants (Hymenoptera: Apoidea,Formicidae) on coconut tree inflorescences (Cocos nucifera,Arecaceae)

Coconut trees are mostly anemophilous; however, because bees and ants forage on coconut tree inflorescences for floral food, entomophilous pollination can also occur. The aim of this study was to determine the food resource preference of bees and ants while they collect pollen, nectar and, for ants, occasionally prey on coconut tree inflorescences, as well as to evaluate their impact on self-pollination. The number of ant visits to first female and then male flowers is significantly higher than that of bees. For Apis mellifera (L.) and Pseudomyrmex gracilis (Fabricius) 14% of the sequences were favorable to direct self-pollination. The probability of visits for all of the sequences was similar for both bees and ants and there was no difference in resource choice. For these reasons, neither can be considered a more effective pollinator of the coconut tree.     

Testing the reproductive groundplan hypothesis in ants (Hymenoptera: Formicidae)

The evolution of complex societies with obligate reproductive division of labor represents one of the major transitions in evolution. In such societies, functionally sterile individuals (workers) perform many of fitness‐relevant behaviors including allomaternal ones, without getting any direct fitness benefits. The question of how such worker division of labor has evolved remains controversial. The reproductive groundplan hypothesis (RGPH) offers a powerful proximate explanation for this evolutionary leap. The RGPH argues that the conserved genetic and endocrinological networks regulating fitness‐relevant behavior (e g. foraging and brood care) in their solitary ancestors have become decoupled from actual reproduction in the worker caste and now generate worker behavioral phenotypes. However, the empirical support for this hypothesis remains limited to a handful of species making its general validity uncertain. In this study, we combine data from the literature with targeted sampling of key species and apply phylogenetically controlled comparative analysis to investigate if the key prediction of the RGPH, namely an association between allomaternal behavior and an allomaternal physiological state holds in the largest and most species‐rich clade of social insects, the ants. Our findings clearly support the RPGH as a general framework to understand the evolution of the worker caste and shed light on one of the major transition in evolutionary history.     

Respiratory physiology and water relations of three species of Pogonomyrmex harvester ants (Hymenoptera: Formicidae)

The respiratory physiology and water relations of three harvester ant species (Pogonomyrmex rugosus Emery, P. occidentalis[Cresson] and P. californicus[Buckley]) were examined at three temperatures (15, 25 and 35°C) using a flow-through respirometry system. As intact ants tended to be active during testing, we performed a parallel set of experiments on individuals rendered motionless by decapitation. Both intact and decapitated ants exhibited discontinuous ventilation. Decapitation caused metabolic rate (V˙CO₂) and burst frequency to decrease in all three species. Burst volume either remained constant or increased after removal of the head, though mass-specific V˙CO₂ was unaffected except in P. rugosus. Mass-specific V˙CO₂s of headless harvesters were comparable with published values derived from motionless specimens of other ant species. The mean Q₁₀ for intact ants of all three species was 2.37; for decapitated insects the mean was 2.32. Respiratory water constituted a small (< 5%) fraction of total loss, and we believe that discontinuous ventilation does not act to conserve water in these organisms, although it may serve other functions.