On the effects of diet and photoperiod on <Emphasis Type=Italic>Harmonia axyridis</Emphasis> (Pallas) (Coleoptera,Coccinellidae) larval development

It is known that the light day length and diet could act as cue factors inducing adult (reproductive) diapause in aphidophagous coccinellids. However, the rate of coccinellid larval development could also depend on photoperiod and diet. The present study examines the effects of photoperiod (L: D = 12: 12 or 16: 8) and diet (the green peach aphid Myzus persicae or eggs of the Angoumois grain moth Sitotroga cerealella) on preimaginal development of the multicolored Asian lady beetle Harmonia axyridis. At 20°C, a short light day and feeding on aphids shortened larval development by 1.4 and 4.6 days, respectively. In combination, both factors caused a simple sum of separate impacts indicating the absence of their interaction. The duration of the pupal stage was independent of photoperiod, but decreased by 0.3 days in individuals fed on aphids. The proportion of the larvae that successfully completed preimaginal development was also independent of the light day length, but significantly depended on diet (84 and 60% in individuals fed on green peach aphids and on grain moth eggs, respectively). In sum, these results suggest that in the case studied, diet does not play the role of cue factor, but directly influences the larval growth and development of H. axyridis.     

Mode of overwintering of invasive <Emphasis Type=Italic>Harmonia axyridis</Emphasis> in the Netherlands

After establishment of Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Europe, population densities of native ladybird species have decreased. The post-hibernation onset of female reproduction, a key characteristic influencing population dynamics and competition with related species, was studied. Hibernating individuals were collected and transferred to outdoor cages to continue overwintering. Every two weeks a sample of individuals was transferred to long-day, warm conditions. Intensity of dormancy was studied by determining the pre-oviposition period and ovarian development. Pre-oviposition periods were short throughout our observations, indicating that Harmonia axyridis was not in diapause but in a quiescent state. H. axyridis becomes active rapidly when temperature rises in spring but is not active earlier in the year than native species. Neither the mode of overwintering, nor the onset of spring activity can explain the invasion success of H. axyridis.     

Color polymorphism,development, and reproductive diapause of the multicolored Asian ladybird <Emphasis Type="Italic">Harmonia axyridis</Emphasis> (Pallas) (Coleoptera,Coccinellidae) females

Preimaginal development and maturation of females of two laboratory strains originated from two populations of the multicolored Asian ladybird Harmonia axyridis were investigated under laboratory conditions. Females of the autochthonous population from Irkutsk (Siberia) enter diapause under the short day conditions, whereas in females of the invasive population from Sochi (the Caucasus) photoperiodic induction of diapause is weak. The two populations also differ in the proportions of morphs: the population from Sochi is represented only by the morph succinea, whereas the population from Irkutsk is represented by the morphs succinea и axyridis with the predominance of the last one, which in our study was separated into two phenotypes, differed in the degree of melanization. Rearing of adults under the short day (12 h) conditions induced reproductive diapause in females of all the studied morphs and phenotypes of the Irkutsk population, whereas under the long day (18 h) conditions females of the morph succinea showed a slightly lower tendency to diapause. Evidently, the interpopulation differences in the responses regulating the seasonal cycle of the multicolored Asian ladybird are determined by genes that are not involved (or almost not involved) in the determination of the color polymorphism. The interpopulation differences in size and weight were quite substantial, whereas the differences between morphs and phenotypes were statistically significant in only some of our experiments. In combination with the literature data, these results suggest that the genes determining the color polymorphism in H. axyridis may have a pleiotropic effect on other traits including important eco-physiological parameters but this effect is relatively weak and manifests itself only against a particular genetic background and / or under particular environmental conditions.     

Differentiation of <Emphasis Type=Italic>Harmonia axyridis</Emphasis> Pall. according to polymorphic morphological traits and variability of the mitochondrial COI gene

The geographic variability of Harmonia axyridis Pall. has been studied with regard to three morphological features. A study of the cytochrome C oxidase subunit I (COI) polymorphism was begun. Two geographically separated zones inside the Russian part of the geographic range of the species are recognized. Interpopulational differences, as judged using polymorphic traits, are very small within each zone. In contrast, the differences between the populations of the western and eastern zones reach the subspecies level of. A zone of clinal variability of morphological traits is noted in Transbaikalia. It obviously resulted from secondary contact between the western and eastern groups of populations, which were separated during the last glaciation and then rejoined.     

Ecology of <Emphasis Type=Italic>Harmonia axyridis</Emphasis> in natural habitats within its native range

Originally distributed in northeast Asia, Harmonia axyridis (Coleoptera: Coccinellidae) is now found throughout much of the temperate zone. In its native area, H. axyridis maintains stable populations in heterogeneous and temporary habitats because of its great ability to find prey and reproduce, coupled with density-dependent and self-regulatory population regulation. A negative correlation of H. axyridis on the biodiversity of the aphidophagous community has been observed in its native range. The decrease in biodiversity may be mainly caused by the wider range of habitats available to H. axyridis than to the coexisting species. From a theoretical perspective, density-dependent regulation of H. axyridis populations, e.g., cannibalism, may be more important in maintaining the H. axyridis-dominated system, probably than is intraguild predation. Habitat heterogeneity may also be important to the coexistence of H. axyridis and other predators in both native and invaded areas.     

The influence of density-dependent factors on larval development in native and invasive populations of <Emphasis Type="Italic">Harmonia axyridis</Emphasis> (Pall.) (Coleoptera,Coccinellidae)

Effects of the number of larvae per Petri dish (1, 5, and 10) on the preimaginal development of individuals of the native (Irkutsk, southern Siberia) and invasive (Sochi, the Northern Caucasus) populations of the multicolored Asian ladybird Harmonia axyridis were investigated in the laboratory. The experiments were conducted under short (12 h) and long (18 h) day conditions; the larvae were fed on the green peach aphid Myzus persicae or on the eggs of the grain moth Sitotroga cerealella. An increase in the number of larvae developed in one Petri dish resulted in a significant decrease in the rate of development in individuals from both populations which fed on aphids. Survival decreased with an increase in the number of larvae developed in one Petri dish fed on both prey species, but only in larvae from the invasive population of H. axyridis. The weight of emerging adults decreased with the number of larvae per dish in individuals from both study populations, but only when fed on aphids. These data suggest that the influence of density-dependent factors on the development of H. axyridis depends significantly on larval prey species. In addition, larvae from the invasive population have somewhat more aggressive interactions with competitors, this possibly having been one of the prerequisites for invasion.     

Paternity following multiple mating in ladybird <Emphasis Type="Italic">Harmonia axyridis</Emphasis>

We investigated factors which may determine realised paternity following multiple mating in a promiscuous ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), namely the mating order and ability of males of different morphs to fertilize females. In experiments using males of two colour morphs, we found that the first male had a reproductive advantage over the second male (sperm precedence P2 = 0.38). Males of the melanic morph spectabilis had a reproductive advantage over males of the semi-melanic morph axyridis (P2 = 0.35). Analysis of paternity using microsatellites applied to young larvae, which avoids possible differential mortality of progeny, confirmed the precedence of the first male and higher paternity rate of colour morphs that are more frequent in the wild. Hatchability of eggs increased from 65% after the first mating to 85% after the second mating delayed by five days. Average duration of mating was 157 min and did not differ between the first and second mating and between the colour morphs of males.     

Presence of <Emphasis Type=Italic>C. albidus</Emphasis>, <Emphasis Type=Italic>C. laurentii</Emphasis> and <Emphasis Type=Italic>C. uniguttulatus</Emphasis> in Crop and Droppings of Pigeon Lofts (<Emphasis Type=Italic>Columba livia</Emphasis>)

Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this disease.     

The global spread of <Emphasis Type="Italic">Harmonia axyridis</Emphasis> (Coleoptera: Coccinellidae): distribution,dispersal and routes of invasion

Released as a biological control agent of aphids and coccids, Harmonia axyridis (Coleoptera: Coccinellidae) has spread from Asia to four additional continents. Since 1988 H. axyridis has established in at least 38 countries in its introduced range: three countries in North America, six in South America, 26 in Europe and three in Africa. In different continents the species has spread at rates estimated between 100 and 500 km year⁻¹. Here, the global spread of H. axyridis is thoroughly reviewed. Mechanisms of short- and long-distance dispersal in coccinellids are discussed, as are the reasons for them, with particular emphasis on H. axyridis. Dispersal via anthropogenic means has been particularly important in the case of H. axyridis. Preliminary studies investigating the invasion routes of H. axyridis using genetic analyses (involving both microsatellite and mitochondrial DNA) are outlined.     

The larval morphology and systematics of the leaf-beetles <Emphasis Type=Italic>Altica deserticola</Emphasis> and <Emphasis Type=Italic>Altica engstroemi</Emphasis> (Coleoptera,Chrysomelidae)

The elder-instar larva of Altica deserticola is described for the first time, and the last-instar larva of A. engstroemi is re-described. The diagnostic characters are included. The former species develops on Glycyrrhiza, and the latter one, on Filipendula ulmaria. Some questions on the general morphology of the larvae of Altica are discussed.     

Habitat,density, and spatial distribution of <Emphasis Type=Italic>Rivulus giarettai</Emphasis> (<Emphasis Type=Italic>Actinopterygii</Emphasis>, <Emphasis Type=Italic>Cyprinodontiformes</Emphasis>) in southeastern Brazil

We present data on the habitat, density, and spatial distribution of Rivulus giarettai, and discuss some biotic and abiotic variables related to its abundance in Free Flowing Waters (FFW) and Dam Reservoirs (DR) in palm grove (Mauritia flexuosa) marshes (Veredas) in Uberlandia, Minas Gerais, southeastern Brazil. The mean density (individuals/plot) of R. giarettai was about 13 times higher in FFW than in DR. In FFW, the density of R. giarettai was highest at intermediate amounts of substrate (plant mass) and it was positively rank-correlated with the depth, and the number of arthropods. Individuals occurred in an aggregated distribution. The aggregated pattern could be related to a concentration of individuals in microhabitats neither too much exposed nor completely saturated by plants. R. giarettai was relatively abundant and tolerant to slight man-made habitat modifications. Damming appeared to be especially problematic by negatively affecting its density.     

On high abundance of the Harlequin lady beetle, <Emphasis Type="Italic">Harmonia axyridis</Emphasis> (Pall.) (Coleoptera,Coccinellidae), in the plains of the Northwestern Caucasus,Russia

The Harlequin lady beetle, Harmonia axyridis (Pallas), is recorded in great numbers in the city of Krasnodar and in the plain part of Krasnodar and Stavropol territories in mid-October 2013. The beetles flew onto walls and windows of the apartment buildings in Krasnodar and were found concentrating in a car and on fruit trees in an orchard in western Stavropol Territory.     

The subspecies of <Emphasis Type=Italic>Chrysolina limbata</Emphasis> (Coleoptera,Chrysomelidae)

Examination of 1492 specimens of Ch. limbata (Fabricius, 1775) from the entire distribution range resulted in the discrimination of six subspecies: limbata (West Europe excluding the Apennine Peninsula, the Crimea, north and south of European Russia, the Great Caucasus, Northern Kazakhstan, and southern West Siberia), discipennis (Ménétriés, 1848) (southeast of European Russia, Western Kazakhstan), hochhuthii (Suffrian, 1851) (south of East Siberia, Eastern Kazakhstan, Mongolia, Northern China), luigionii (Depoli, 1936) (the Apennines, the Alps, Herzegovina, the Mediterranean coast of France); russiella ssp. n. (deciduous forests, forest-steppe and steppe of European Russia and Ukraine); volodi ssp. n. (alpine regions of the Lesser Caucasus and eastern Turkey). Ch. limbata findelii (Suffrian, 1851) is a new junior synonym of Ch. limbata limbata.