Predation potential of <Emphasis Type="Italic">Rhynocoris marginatus</Emphasis> (Hemiptera: Reduviidae) against three mealybug species of agricultural importance

The predation potential of a generalist predator Rhynocoris marginatus (Fab.) (Hemiptera: Reduviidae) against three important mealybug pests of cotton, Phenacoccus solenopsis Tinsley, Maconellicoccus hirsutus Green, and Coccidohystrix insolita Green (Hemiptera: Pseudococcidae) was evaluated under laboratory conditions. The specific objective of the study was to determine the prey capturing time, prey handling time, and prey preference among the three mealybug species for different developmental stages of R. marginatus. The number of prey consumed/predator/24 h by R. marginatus was dependent on the mealybug species and the predator developmental stage. Rhynocoris marginatus showed a decrease in prey capturing time and handling time as the predator grew older. After evaluating the prey stage preference, results indicated that the developmental stages of R. marginatus preferred adult mealybugs over the younger stages. In a choice-test bioassay including the three mealybug species, no significant difference in prey species selection was observed for the various R. marginatus developmental stages. However, the mortality of P. solenopsis was observed to be highest among the mealybugs, followed by M. hirsutus and C. insolita. This supports the idea that R. marginatus can be effectively utilized for the management of one of the most destructive mealybug pests of cotton, P. solenopsis. Results from this study are important for the development of a knowledge-based management program for cotton agroecosystems affected by various mealybug pests.     

Reduced ant defenses in <Emphasis Type="Italic">Macaranga</Emphasis> myrmecophytes (Euphorbiaceae) infested with a winged phasmid <Emphasis Type="Italic">Orthomeria cuprinus</Emphasis>

Macaranga is a tree genus that includes many species of myrmecophytes, which are plants that harbor ant colonies within hollow structures known as domatia. The symbiotic ants (plant–ants) protect their host plants against herbivores; this defense mechanism is called ‘ant defense’. A Bornean phasmid species Orthomeria cuprinus feeds on two myrmecophytic Macaranga species, Macaranga beccariana and Macaranga hypoleuca, which are obligately associated with Crematogaster ant species. The phasmids elude the ant defense using specialized behavior. However, the mechanisms used by the phasmid to overcome ant defenses have been insufficiently elucidated. We hypothesized that O. cuprinus only feeds on individual plants with weakened ant defenses. To test the hypothesis, we compared the ant defense intensity in phasmid-infested and non-infested M. beccariana trees. The number of plant–ants on the plant surface, the ratio of plant–ant biomass to tree biomass, and the aggressiveness of plant–ants towards experimentally introduced herbivores were significantly lower on the phasmid-infested trees than on the non-infested trees. The phasmid nymphs experimentally introduced into non-infested trees, compared with those experimentally introduced into phasmid-infested trees, were more active on the plant surface, avoiding the plant–ants. These results support the hypothesis and suggest that ant defenses on non-infested trees effectively prevent the phasmids from remaining on the plants. Thus, we suggest that O. cuprinus feeds only on the individual M. beccariana trees having decreased ant defenses, although the factors that reduce the intensity of the ant defenses remain unclear.     

Mortal combat between ants and caterpillars: an ominous threat to the endangered Schaus swallowtail butterfly (<Emphasis Type="Italic">Heraclides aristodemus ponceanus</Emphasis>) in the Florida Keys,USA

The federally endangered Schaus swallowtail butterfly (Heraclides aristodemus ponceanus) has reached critically low numbers. Exotic ants are a potential threat to H. a. ponceanus and other rare butterflies as they can attack immature stages. Ant surveys conducted in subtropical dry forests in Biscayne National Park documented ant species diversity and relative abundance. A caterpillar predator exclusion experiment using physical barriers in different combinations evaluated caterpillar survivorship of both early and late instar caterpillars exposed to different threats. Ant-caterpillar interactions were also documented by placing caterpillars on plants and observing physical interactions between caterpillars and ants. A total of 1418 ants comprising 25 ant species was captured and identified. In canopies of H. a. ponceanus host plants, 243 ants comprising 12 species were found. The four most common ants collected in the host plant canopies were Pseudomyrmex gracilis, Camponotus planatus, Cremastogaster ashmeadi, and Camponotus floridanus. The predator exclusion experiment revealed survivorship was significantly lower for early and late instar caterpillars without any physical barrier, as well as for early instars not protected by a mesh cage. Pseudomyrmex gracilis and C. floridanus were more aggressive towards caterpillars in comparison to other ant species; these two species ranked first and second in the “ant danger index” ranking predatory abilities of the four most common ant species. Pseudomyrmex gracilis is a common arboreal exotic ant in Biscayne National Park and presents a major threat to caterpillars during their earliest life stages.     

The presence of an alternative food source changes the tending behavior of the big-headed ant, <Emphasis Type="Italic">Pheidole megacephala</Emphasis> (Hymenoptera: Formicidae) on <Emphasis Type="Italic">Dysmicoccus brevipes</Emphasis> (Homoptera: Pseudococcidae)

The mutualistic association between ants and hemipterans is often facultative and can be affected by the availability of other food sources. In the present study we tested whether the tending behavior of the big-headed ant, Pheidole megacephala (Fabricius), had a negative impact on the pink pineapple mealybug, Dysmicoccus brevipes (Cockerell), when alternative food sources: (1) sugar solution, (2) purified water + mealworms and (3) sugar solution + mealworms versus with purified water (control) were provided to the ant colonies. We found that the frequency of ant tending on D. brevipes decreased when ants were provided with alternative food sources. However, we did not see any aggressive behaviors and predation of ants on D. brevipes. Also, the survival of D. brevipes was not different among food condition treatments. These results suggest that the decreased tending frequency of ants can lead to the decline in ant protection service to mealybugs.     

Behavioral strategy of a lycaenid (Lepidoptera) caterpillar against aggressive ants in a Brazilian savanna

Myrmecophily is widespread in lycaenid butterflies, in which ants receive food resources and, in turn, protect caterpillars against natural enemies. This interaction ranges from obligate myrmecophily, in which immatures are invariably associated with ants and are dependent on ants for survival, and facultative myrmecophily, in which larvae are not dependent on ants for survival, but the presence of the latter may increase larvae survival. Lycaenids also include non-myrmecophilous butterflies, which do not have positive associations with ants and have developed strategies to avoid being attacked or preyed upon by them. In this study, we examined the relationship between the lycaenid Michaelus ira and two ant species associated with Distictella elongata (Bignoniaceae). This plant has extrafloral nectaries and is patrolled by Camponotus crassus and Ectatomma tuberculatum. Morphological analyses revealed that M. ira larvae have ant organs, such as dorsal nectary organs and perforated cupolas, structures associated with myrmecophily. We performed larval exposure experiments in the field, predicting that, in the absence of myrmecophily, the butterfly larva would present strategies to avoid ant attack. Results showed that larvae were attacked by both ant species. To escape ant molestation, larvae lived and fed inside silk-sealed D. elongata flower buds. We concluded that the M. ira bud-sheltering behavior was a defensive strategy against these ant species, while the dorsal nectary organs were apparently nonfunctional. Nonetheless, myrmecophily, in general, cannot be excluded in M. ira since relationships with other ant species may exist.     

Larvae of the exotic predatory ladybird <Emphasis Type="Italic">Platynaspidius maculosus</Emphasis> (Coleoptera: Coccinellidae) on citrus trees: prey aphid species and behavioral interactions with aphid-attending ants in Japan

An aphidophagous ladybird, Platynaspidius maculosus (Weise) (Coleoptera: Coccinellidae), is originally distributed in China, Taiwan, and Vietnam. The ladybird has recently intruded into the southern and central parts of Japan. The present study found that the larvae of this ladybird preyed on three aphid species, Aphis spiraecola, Aphis gossypii, and Toxoptera citricidus (all Hemiptera: Aphididae), feeding on young shoots of various Citrus species in August to early October in Shizuoka Prefecture, central Japan. Laboratory rearing of the sampled larvae confirmed that the larvae completed their development (adult emergence) by consuming each of the three aphid species. The ladybird larvae were observed foraging in aphid colonies attended by one of the four ants, Lasius japonicus, Pristomyrmex punctatus, Formica japonica, and Camponotus japonicus (all Hymenoptera: Formicidae). Field observations revealed that the foraging/feeding larvae were almost completely ignored by honeydew-collecting ants even when they physically contacted each other. Thus, in Japan, the larvae of the exotic ladybird exploit colonies of the three aphid species attended by one of the four ant species on many Citrus species. On the basis of the results, I discuss the possibility of the ladybird’s reproduction on citrus trees in Japan, probable adaptations of the ladybird larvae to aphid-attending ants, and potential impacts of the ladybird on native insect enemies attacking ant-attended aphids on citrus.     

Composition of harvested seeds and seed selection by the invasive tropical fire ant, <Emphasis Type="Italic">Solenopsis geminata</Emphasis> (Hymenoptera: Formicidae) in Taiwan

Solenopsis geminata (F.) is an invasive ant that is widely distributed in weedy areas and agricultural fields in Taiwan. Previous studies have found that S. geminata harvests the seeds of numerous plants. In the present study, we further investigated the composition of harvested seeds in ant nests and seed selection by workers. The seed caches in S. geminata nests sampled in eight areas in Taiwan suggest that the seeds harvested by workers were diverse and belonged to 52 plant species in 17 plant families. Twenty-three species (44%) belong to the family Gramineae, and most of the seeds weighed from 0.02 to 2.29 mg, which might suggest that these are the main seeds harvested by S. geminata from their habitat. Ten common species with similar seed weights were used to compare the seed preferences of workers from two experimental sites. The results suggest that the seed preference was different between the two experimental sites. The seeds of Casuarina equisetifolia showed the most obvious difference in seed removal speed, which might suggest that S. geminata potentially prefers the encountered seed species in the habitat. The various plant species in the ant nests and seed preference suggest that fire ants easily accept newly encountered plant species. As more than half of the plant species (52%) and the total seed number (63%) belonged to exotic species, the role of S. geminata might be negative because it tends to harvest exotic seeds and has a high opportunity to improve the establishment of exotic seedlings.     

Ants Associated with <Emphasis Type="Italic">Turnera subulata</Emphasis> (Turneraceae): Elaiosome Attraction,Seed Dispersion and Germination

Symbiosis between plants and ants include examples in which the plant provides shelter and/or food for ants that, in turn, act in the defense or in the dispersion of seeds from the host plant. Although traditionally referred as mutualistic, the results of these interactions may vary with the ecological context in which patterns are involved. A range of species have facultative association with Turnera subulata (Turneraceae). Here, using behavioral bioassays, we investigated the effects of the most frequent ant species associated with T. subulata (Brachymyrmex sp.1, Camponotus blandus (Smith), Dorymyrmex sp.1, Crematogaster obscurata Emery, and Solenopsis invicta Buren) in the dispersion of plant host seeds and in the number of seedlings around the associated ant nests. We also evaluated the effects of these ant species in the germination of T. subulata seeds, in the consumption of elaiosome, and in the attractiveness to elaiosome odor. Our results showed that the ant species associated with T. subulata presented variation in the attraction by the odor and in the rate of consumption of the elaiosomes. However, none of the ant species studied contributed significantly to the increase of seed germination and seedling growth. Our results suggest that the consumption of the elaiosome by ant species is not a determinant factor to the success of germination of T. subulata. However, such species could contribute indirectly to seed germination by carrying seeds to sites more fertile to germination. In general, our results help to elucidate the results of ecological interactions involving ants and plants.     

Mass Occurrence and Dominant Behavior of the European Ant Species <Emphasis Type="Italic">Formica fuscocinerea</Emphasis> (Forel)

Recently, masses of the ant Formica (Serviformica) fuscocinerea (Forel) have been occurring at numerous sites in Southern Germany. Although F. fuscocinerea is native to Southern Germany, these mass occurrences resemble ant invasions in density and dominance. This study aimed to investigate the underlying mechanisms that promote sudden mass occurrence of a previously inconspicuous ant species within its native range. To estimate the competitive dominance of F. fuscocinerea, species occurrence and abundance considering biotic and abiotic parameters were studied in a natural habitat where F. fuscocinerea co-occurred with two other common ant species, Myrmica ruginodis (Nylander) and Lasius niger (Linnaeus). To understand the species’ distribution in the field, laboratory experiments on interspecific competition were conducted. Finally, the colony structure of F. fuscocinerea was investigated with intraspecific aggression tests. Formica fuscocinerea dominated an area that, as indicated by strongly frequented foraging trails on the trees, provided important food sources, e.g. trophobionts, to the ants. Other ant species coexisted only at the periphery of the F. fuscocinerea range. Laboratory experiments revealed F. fuscocinerea as highly dominant species. Additionally, F. fuscocinerea showed a complete lack of intraspecific aggression between ants originating from distances up to 58 km, indicating weak or nonexistent behavioral boundaries among ants of physically separated nests. Since extraordinarily high worker densities, strong interspecific dominance and a lack of colony boundaries within supercolonies are considered to be important traits of several invasive ant species we conclude that the same traits also promote the dominance of F. fuscocinerea.     

Ants Do Not Traverse the Silk of Adult Female <Emphasis Type="Italic">Nephila clavipes</Emphasis> (Linnaeus) Webs

Many organisms use chemicals to deter enemies. Some spiders can modify the composition of their silk to deter predators from climbing onto their webs. The Malaysian golden orb-weaver Nephila antipodiana (Walckenaer) produces silk containing an alkaloid (2-pyrrolidinone) that functions as a defense against ant invasion—ants avoid silk containing this chemical. In the present study, we test the generality of ants’ silk avoidance behavior in the field. We introduced three ant species to the orb webs of Nephila clavipes (Linnaeus) in the tropical rainforest of La Selva, Costa Rica. We found that predatory army ants (Eciton burchellii Westwood) as well as non-predatory leaf-cutting ants (Atta cephalotes Linnaeus and Acromyrmex volcanus Wheeler) avoided adult N. clavipes silk, suggesting that an additional species within genus Nephila may possess ant-deterring silk. Our field assay also suggests that silk avoidance behavior is found in multiple ant species.     

A New Species of <Emphasis Type="Italic">Paracoccus</Emphasis> Ezzat and McConnell (Hemiptera: Pseudococcidae) from Southern Brazil

The worldwide mealybug genus Paracoccus Ezzat & McConnell (Hemiptera: Coccomorpha: Pseudococcidae) has eight described Neotropical species, including two species known from Brazil. In this article, we describe a third species from Brazil: Paracoccus galzerae Pacheco da Silva & Kaydan sp. n., based on the morphology of adult females collected on the roots of Conyza bonariensis (Asteraceae) in vineyards in Bento Gonçalves City, Rio Grande do Sul. A revised identification key including the new species is provided for the Neotropical region.     

Ants (Hymenoptera: Formicidae) as potential egg predators of lepidopteran pests of sweet potato, <Emphasis Type="Italic">Ipomoea batatas</Emphasis> (Solanales: Convolvulaceae), in Japan

The sweet potato Ipomoea batatas (L.) Lam., which has extrafloral nectaries, was visited by nine indigenous ant species in south Kyushu, Japan. These ant species were evaluated for their ability to remove the eggs of two lepidopteran species—Aedia leucomelas (Linnaeus) and Spodoptera litura (Fabricius)—through ant-exclusion experiments. The results showed that Tetramorium bicarinatum (Nylander), one of the dominant ant species, is an efficient predator of lepidopteran eggs. This ant species removed A. leucomelas eggs from ant-visited plants in six trials conducted from mid-July to mid-October, with high removal rates (90–100%) occurring from mid-September onward. On ant-excluded plants, only 0–18% of exposed eggs were removed by ants that accidentally invaded the plants. Tetramorium bicarinatum also removed egg masses and the hatchlings of S. litura. The mean percent area of egg-laden leaves eaten by S. litura larvae was lower on ant-visited plants (0.9%) than on ant-excluded plants (57.3%). In contrast, Formica japonica Motschulsky, another dominant ant species, was not observed removing the eggs or larvae of the lepidopteran species. These results show that certain indigenous ant species are efficient as biocontrol agents. Thus, individual ant species need to be investigated for their ability to control insect pests in various crops.     

Ant interactions with native and exotic seeds in the Patagonian steppe: Influence of seed traits,disturbance levels and ant assemblage

Invasive plants may establish strong interactions with species in their new range which could limit or enhance their establishment and spread. These interactions depend upon traits of the invader and the recipient community, and may alter interactions among native species. In the Patagonian steppe we studied interactions of native ant assemblages with seeds of native and exotic plants, and asked whether ant–seed interactions differ with seed types and disturbance levels and whether the amount and type of ant–seed interactions can be predicted if both ant and seed traits are known. To characterize and quantify ant–seed interactions, we offered baits with large seeds of Pappostipa speciosa (native) and medium-sized elaiosome-bearing seeds of Carduus thoermeri (exotic), near and far from a road (high vs. low disturbed areas), and compared ant abundance and composition between areas. Interaction frequency was the highest for C. thoermeri seeds far from the road. Composition of ants interacting with C. thoermeri in these areas differed from that near the road and from that interacting with native seeds. Ant composition and abundance were similar between areas, but some species interacted more with exotic seeds in low disturbed areas. Ant foraging type predicted ant–seed interactions since the abundance of seed harvesters was positively correlated to interactions with P. speciosa, and that of generalists and predators, with interactions with C. thoermeri. The high interaction of ants with exotic seeds in low invaded areas suggests that ant activity could influence plant invasion, either by predating or dispersing seeds of invasive plants.     

Interaction between a threatened endemic plant (<Emphasis Type="Italic">Anchusa crispa</Emphasis>) and the invasive Argentine ant (<Emphasis Type="Italic">Linepithema humile</Emphasis>)

Seed dispersal mutualisms are essential to ensure the survival of diverse plant species and communities worldwide. Here, we investigated whether the invasive Argentine ant can replace native ants by fulfilling their functional role in the seed dispersal of the rare and threatened endemic myrmecochorous plant, Anchusa crispa, in Corsica (France). Our study addressed the potential of Linepithema humile to disperse elaiosome-bearing seeds of A. crispa, examining L. humile’s effects on (1) the composition of communities of ants removing seeds, (2) the number of seed removals, (3) seed preference, (4) the distance of seed dispersion, and (5) seed germination. We caught seven native species at the control site, but only the Argentine ant at invaded sites. L humile removed A. crispa seeds in greater numbers than did native ants, respectively 66 and 23%, probably due to their higher worker density. The invader was similar to native ants with respect to distance of seed transport. Finally, rates of seed germination were not significantly different between seeds previously in contact with either Argentine ants or not. Taken all together, these results suggest that the Argentine ant is unlikely to pose a threat to A. crispa population. These results have important implications for the management of this rare and threatened endemic plant and provide an example of non-negative interactions between invasive and native species.     

Spatial and Temporal Variation of Plant Fragment Removal by Two Species of <Emphasis Type="Italic">Atta</Emphasis> Leaf-Cutting Ants

Leaf-cutting ants are responsible for much of living plant fragment removal in Neotropical regions, causing major damage in both in natural and agricultural systems. To understand the variation in plant fragment removal by leaf-cutting ants and the influence that temporal and spatial factors have on such variation, we evaluated plant fragments collected by two ant species, Atta laevigata and A. sexdens rubropilosa in different seasons (rainy and dry) and in different forest systems (natural area of cerrado sensu stricto and monoculture of Eucalyptus sp.) in 2014 in Goianésia, Goiás, Brazil. Heavier plant fragments were removed during the dry season and in monoculture areas; A. laevigata removed heavier fragments than A. sexdens rubropilosa. Furthermore, we observed a positive association between the weight of collected fragments and the weight of worker ants and higher weights in A. laevigata. The study shows that the weight of plant fragments removed by leaf-cutting ants is conditioned temporally and spatially, and by the ant species involved. More detailed studies of each of these factors are need to better understand the dynamics of these foraging ants and how abiotic and biotic factors affect this process.     

Vetch aphid, <Emphasis Type="Italic">Megoura crassicauda</Emphasis> (Hemiptera: Aphididae), parasitism does not reduce the bean production of narrow-leaved vetch, <Emphasis Type="Italic">Vicia sativa</Emphasis> subsp. <Emphasis Type="Italic">nigra</Emphasis> (Fabaceae)

Megoura crassicauda Mordvilko (Hemiptera: Aphididae) is a dominant aphid species found on Vicia sativa subsp. nigra (L.) Ehrh. (Fabaceae) in the spring. Worker ants of Formica japonica, the dominant ant species attracted to the extrafloral nectaries of V. s. nigra, often attack ladybirds (Coccinella septempunctata), which are aphid enemies. However, the workers of F. japonica do not attack or exclude M. crassicauda, the non-myrmecophilous aphid. It appears that the “bodyguard” retained by the plant guards the plant’s herbivore by attacking the herbivores’ enemies, rather than guarding the plant itself. The relationship between V. s. nigra and M. crassicauda was observed in the field to examine and evaluate the cost of parasitism. Parasitism by M. crassicauda delayed flower bud formation markedly in V. s. nigra but did not kill the plants. V. s. nigra plants that were parasitized showed a net bean production similar to that of the non-parasitized controls. The parasitism rate of M. crassicauda increased when extrafloral nectaries were used by F. japonica. These results may indicate that M. crassicauda provides V. s. nigra with benefits by preventing other serious disadvantages.     

Stratification of the ant species (Hymenoptera,Formicidae) in the urban broadleaf woodlands of the city of Kiev

Investigations were carried out in June–August 2012 and 2013 in broadleaf forests and planted stands of the northern red oak Quercus rubra in Kiev. The ant visitation rates of 3–6 most abundant plant species within each vegetation layer were analyzed. In all, 16 species of ants were found in the broadleaf forest (Quercus robur + Acer spp. + Carpinus betulus), with the dominance of three species: Formica rufa, Lasius fuliginosus, and L. emarginatus. Eight ant species occurred in Q. rubra stands with the undergrowth of Acer campestre and A. platanoides; the dominant species were Lasius fuliginosus and L. emarginatus. The northern red oak stands with conspecific undergrowth had only four ant species with no dominants among them. Plants with the highest ant visitation rates in the herbage layer of the broadleaf forest were the invasive Impatiens parviflora and the native Aegopodium podagraria. Ants were rare or absent on the remaining herbs: Impatiens noli-tangere, Carex sylvatica, Stellaria holostea, and Galium odoratum. The herbage layer was mostly visited by influents, the dominants being represented only by Lasius emarginatus. Within the shrub layer, ants most frequently visited the undergrowth of the maple Acer platanoides, often harboring colonies of the aphid Periphyllus lyropictus; the highest visitation rates were recorded in the dominants L. emarginatus and L. fuliginosus. The arboreal layer had the highest visitation rate and was most often visited by the dominants Lasius fuliginosus, L. emarginatus, and F. rufa. The common oak Q. robur was the most visited tree in broadleaf forests. In addition to providing ants with food (colonies of the aphids Lachnus roboris and Stomaphis quercus, and also phytophagous insects and other invertebrates), these trees were used for nesting by the dominants L. fuliginosus and L. emarginatus. The presence of aphid colonies was also typical of ripe trees and undergrowth of the maple A. platanoides, the second-visited tree in broadleaf forests. The common hornbeam Carpinus betulus was the least frequently visited, though some ant species, usually L. emarginatus, nested in the trunks and branches of old trees. The vertical distribution of ants in broadleaf forests and red oak stands formed two clusters: the influents occupied the lower (herbage and shrub) vegetation layers, while the subdominants and dominants occupied the upper (shrub and arboreal) ones. The smallest number of ant species (1 or 2) in all the vegetation layers was recorded in the areas with F. rufa; areas with L. fuliginosus had twice as many species; the greatest numbers of ant species were found in the areas with L. emarginatus and in those without dominants. This pattern may result from different territoriality of the dominants: the strongest in F. rufa (defending the whole territory) and the weaker in the other two species (defending only a part of the territory). Plants of all the vegetation layers varied in their attractiveness to ants. As a result, the layers had a mosaic structure in their vertical (between-layer) and horizontal (between different plant species within one layer) arrangement. From 60 to 100% of plants of certain species were visited by ants while plants of other species were not visited at all. The main reason for visiting plants by ants was the presence of aphid colonies.     

Taxonomy and First Records of Two <Emphasis Type="Italic">Megaselia</Emphasis> Rondani Species (Diptera: Phoridae) Preying upon Eggs of <Emphasis Type="Italic">Phyllomedusa iheringii</Emphasis> Boulenger (Anura: Phyllomedusidae)

Non-aquatic reproductive modes have evolved among frogs possibly favored by some advantages such as the avoidance of aquatic predators. These reproductive modes, however, make the egg clutches susceptible to terrestrial predators, among which Diptera larvae are some of the most harmful. The present work reports the predation by phorid flies of 22 egg clutches of Phyllomedusa iheringii Boulenger in the South of Brazil. Phorid specimens were identified as Megaselia bruchiana (Borgmeier & Schmitz) and Megaselia necrophaga (Enderlein), species that were reported previously to be associated with ants and dead beetles, respectively. Frog-feeding in these species is hypothesized to be use of an alternative seasonal food source. We amend the diagnoses of both Megaselia species and provide new illustrations to facilitate their identification. We also describe the male of M. bruchiana for the first time and associate males with females of both species.     

The importance of resource distribution: spatial co-occurrence of host plants and host ants coincides with increased egg densities of the Dusky Large Blue <Emphasis Type="Italic">Maculinea nausithous</Emphasis> (Lepidoptera: Lycaenidae)

The occurrence of the Dusky Large Blue Butterfly (Maculinea nausithous) critically depends on the availability of two key resources: the Great Burnet (Sanguisorba officinalis) as primary nectar source for adults, for egg laying and early larval development, and the host ant Myrmica rubra as the food of late instar larvae. Thus, their distributions are key parameters shaping habitat suitability, and we expected that overlapping of both resources would have a strong impact on the size of local M. nausithous populations. Their egg density may be affected (a) by the fraction of host plants per site located within My. rubra activity ranges at the patch scale, or (b) by the availability of host plants with host ants in close range at the local scale, due to the potential ability of butterfly females to detect their host ants. To test the above hypothesis, we recorded spatial distribution patterns of host plants and host ants on 29 study sites in south-western Germany and related them to egg density data of M. nausithous. We found a positive relationship between co-occurence of host plant and host ant and M. nausithous egg density at the patch scale, whereas no correlation was found at the local scale. Thus, focal populations are strongly limited by the abundance of host plants, covered with My. rubra activity, as ant-mediated oviposition could not be proved. Our results underline the importance of resource distribution; the understanding of its impacts may provide useful insights into how M. nausithous habitats can be managed in order increase their carrying capacity.     

Fen meadows on the move for the conservation of <Emphasis Type="Italic">Maculinea (Phengaris) teleius</Emphasis> butterflies

In the Netherlands, a single population of the obligate myrmecophilic butterfly Maculinea (Phengaris) teleius has survived on only 3 ha of habitat for more than 25 years, whereas at least 40 ha of habitat are thought to be required for a sustainable metapopulation. Therefore, 170 ha of farmland is being restored to wet meadows within a LIFE?+?project by large-scale soil excavation and hay inoculation. For successful restoration, the habitat requirements of the butterfly, with Sanguisorba officinalis as host plant and its particular life cycle as parasite of the ant species Myrmica scabrinodis, have to be taken into account. We tested whether colonization of nests of this ant species in the restoration areas is facilitated by translocation of sods collected from fen meadows. We divided 54 sods, each sized 1 m², randomly over six patches and measured vegetation development and ant presence in the sods and surrounding control plots for 2 years. In the first summer, significantly more Myrmica ants were found in the transplanted sods in comparison to the surrounding area. Herb cover had a significant positive effect on Myrmica ant presence while it did not affect the presence of the pioneer ant species Lasius niger. In the second year, Myrmica ants were found in the surrounding control plots as well. This study contributes to the knowledge-base required for the design of restoration projects aimed at expanding the habitat of the critically endangered butterfly Maculinea (Phengaris) teleius.