This review considers factors affecting the flight capacity of carabid beetles and the implications of flight for carabids. Studies from the Dutch polders in particular show that young populations of carabids consist predominantly of macropterous species and macropterous individuals of wing-dimorphic species. Also populations of wing-dimorphic carabid species at the periphery of their geographical range contain high proportions of macropterous individuals. However, studies from Baltic archipelagos show that older populations of even highly isolated island habitats contain considerable proportions of brachypterous species and individuals. This suggests that macroptery is primarily an adaptation for dispersal and that there exists a mechanism for subsequently reducing the ratio of macropterous to brachypterous species under stable conditions, due to the competitive advantage of brachyptery. Populations in isolated habitats, such as islands and mountains, have high proportions of brachypterous species. Many macropterous species do not possess functional flight muscles. Species of unstable habitats, such as tree canopies and wet habitats, are mostly macropterous. Brachypterous species tend to disappear from disturbed habitats. There is uncertainty regarding the extent to which carabid dispersal is directed and how much passive. Both Den Boer and Lindroth recognized that mostly macropterous individuals of macropterous and wing-dimorphic species disperse and found new populations, after which brachyptery tends to rapidly appear and proliferate in the newly founded population. It is most likely that the allele for brachyptery would arrive via the dispersal of gravid females which had mated with brachypterous males prior to emigration. Whilst many studies consider wing morphology traits of carabid beetles to be species-specific and permanent, a number of studies have shown that the oogenesis flight syndrome, whereby females undertake migration and subsequently lose their flight muscles by histolysis before eventually regenerating them after reproducing, has been reported for a growing number of carabid species. Wing morphology of carabid beetles clearly offers strong potential for the study of population dynamics. This field of study flourished during the 1940's to the late 1980's. Whilst a considerable amount of valuable research has been performed and published, the topic clearly holds considerable potential for future study., Stephen Venn., and Obsahuje bibliografii
Ectrichodiinae (Hemiptera: Reduviidae), the millipede assassin bugs, are a speciose group (>660 species) of assassin bugs that appear to be specialist predators on Diplopoda, or millipedes. Apparently capable of coping with the noxious defensive compounds produced by many millipedes, Ectrichodiinae are engaged in a predator-prey relationship with millipedes realized only by few other arthropods. Unfortunately, feeding behaviors of Ectrichodiinae are inadequately documented, rendering this exciting phenomenon largely inaccessible. We here present a literature review on ectrichodiine prey selection and feeding behaviors, with supplemental original observations on Rhiginia cinctiventris (Stål, 1872) in Costa Rica. Thirteen species in 12 genera have been observed to feed on millipedes. The majority of diplopod prey species were reported from the orders Spirostreptida and Spirobolida, whereas Polydesmida are rarely attacked. Ectrichodiinae insert their stylets at the millipede’s intersegmental membranes on the ventral and ventro-lateral trunk area or between the head and collum. Communal predation was observed among conspecific nymphs, among groups of nymphs with a conspecific adult, and more rarely among adults. Immature ectrichodiines were rarely observed to engage in solitary predation. Observations on R. cinctiventris indicate that this species preys on spirobolid and polydesmid millipedes and are in agreement with behaviors described for other Ectrichodiinae., Michael Forthman, Christiane Weirauch., and Obsahuje seznam literatury
Interactions involving host plants (cowpea, groundnut, cotton, sunflower, greengram, blackgram) an insect herbivore, black legume aphid Aphis craccivora Koch (Hemiptera: Aphididae) and a predator, the zigzag beetle Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae) were investigated during 2014-2015. The preference of the aphid A. craccivora for host plants measured in terms of growth and multiplication was cowpea > groundnut > greengram > blackgram > sunflower > cotton (most preferred to least preferred). Cowpea was the most preferred host plant for growth and multiplication of A. craccivora. Aphid's oviposition period was longest, fecundity greatest; adult longevity longest (188.40 ± 28.87 h; 52.00 ± 10.92; 231.60 ± 40.41 h), and nymphal mortality was lowest (0%) when reared on cowpea followed by groundnut, greengram and blackgram. Aphids had highest nymphal mortality (100%), with very few or no live adults produced, when reared on sunflower and cotton, the least preferred host of A. craccivora in this study. At the third trophic level, both the larvae and the adults of the coccinellid, Cheilomenes sexmaculata, consumed more of the aphids reared on groundnut than of those reared on blackgram, greengram, cowpea, sunflower and cotton. The biochemical constituents (phenols) present in cotton and sunflower, which contributed to the aphid's nymphal mortality, also affected the feeding behaviour of the coccinellid., Snehasish Routray, Karnam V. Hari Prasad., and Obsahuje bibliografii
Ovipositing females from invasive (Krasnodar Territory of Russia) and native (Far East of Russia) populations of Harmonia axyridis were fed one of a set of diets ranging from 50 Myzus persicae aphids every day to 1 aphid every 10 days and all were also provided with a 10% sugar solution. The experiment was conducted at 20°C under short (12 h) and long (18 h) day conditions. Most of the females from the native population that consumed 50 or 10 aphids per day continued to oviposit under both long and short day conditions. Females that consumed 1 aphid per day or every 2 days practically stopped laying eggs but under long day conditions their ovaries were still active, whereas under short day conditions ca 50% of them were reproductively inactive (only germaria present) and had a well-developed fat body. Further reduction in diet resulted in an increase in the proportion of reproductively inactive females. However, about half of the females that terminated oogenesis under long day conditions had poorly developed fat bodies, which indicates that diapause was not induced. For the females from the invasive population, both photoperiodic and trophic effects were weak: under short day conditions, some females entered diapause when prey was abundant, whereas about 50% (independent of photoperiod) did not enter diapause when starved. This risk-spreading strategy, possibly, facilitates the adaptation of this invasive ladybird to unpredictable environmental conditions., Antonina A. Ovchinnikova, Andrey N. Ovchinnikov, Margarita Yu. Dolgovskaya, Sergey Ya. Reznik, Natalia A. Belyakova., and Obsahuje bibliografii
1_The arboricolous dolichoderine ant Liometopum microcephalum (Panzer, 1798) is considered to be mainly predatory, although there are some reports of it tending aphids. The main objective of the present study was to confirm that this ant has a trophobiotic relationship with aphids and assess seasonal differences in its utilization of honeydew. We hypothesized that the worker ants on trees where they have their nest (nest tree) and trees where they are foraging (foraging trees) should differ in gaster mass and sugar content depending on their direction of movement, and that both should be highest in spring. From spring to summer 2009, ascending and descending workers were collected from nest and foraging trees at a locality in South Moravia, Czech Republic. Mass of their gasters and their content of total and reducing sugars were measured using chemical (photometric) methods. Differences in gaster mass confirmed the flow of liquid food from foraging to nest trees, but there were no significant between-month differences. Contents of total and reducing sugars were positively correlated with gaster mass. The gasters of workers descending from foraging trees contained significantly more reducing sugars than those of workers descending or ascending nest trees. The content of reducing sugars was lowest at the beginning of the ants’ activity period in April and highest in June, with a non-significant drop in July. Results for total sugars were similar, with the decrease in July being significant. The concentration of sugars in the gasters of workers ascending and descending nest trees did not differ significantly but the absolute content of total sugars was higher in the gasters of ascending ants., 2_Results from foraging trees confirmed that the ants collected the honeydew from these trees. Possible reasons for the ambigous results for nest trees are discussed. We conclude that trophobiosis is an important component of the nutritional biology of L. microcephalum., Jiří Schlaghamerský ... []., and Obsahuje seznam literatury
Tropické lesy ostrova Borneo v jihovýchodní Asii jsou celosvětově výjimečné vysokou biodiverzitou různých skupin organismů. Jejich podoba byla formována mimo jiné během čtvrtohorního kolísání hladiny světových oceánů, kdy byly ostrovy sundské oblasti vzájemně propojeny či odděleny, což mělo vliv na migraci organismů. Současná diverzita lesů Bornea sleduje gradient nadmořské výšky a vlastnosti substrátů, přičemž můžeme rozlišit několik hlavních typů lesa. V posledních desetiletích jsme svědky masivní těžby lesů, které jsou mnohde převáděny na plantáže palmy olejné., Tropical forests of the island of Borneo in South East Asia harbour an extraordinary high biodiversity of various groups of organisms. They have been shaped, among other influences, by the Quaternary fluctuations of the level of world’s oceans, connecting or dividing islands within the Sundaland, which has affected migration of species. The present diversity of forests in Borneo follows an elevational gradient and substrate properties, thus forming several main forest types. Over the past few decades, we have witnessed massive logging and transformation of forests into oil palm (Elaeis guineensis) plantations., Radim Hédl., and Obsahuje seznam literatury
Ten amber inclusions of male Ripidiinae (Coleoptera: Ripiphoridae) are reported from Early Miocene deposits of the Dominican Republic and compared with extant species of Neorrhipidius Viana, 1958 from Argentina and Paraguay and Quasipirhidius Zaragoza Caballero, 1991 from Mexico. Neorrhipidius seicherti sp. n. and Quasipirhidius luzziae sp. n. are described and illustrated. Both species are characterised by 11-segmented antennae with eight distal antennomeres uniflabellate, mouthparts reduced to maxillary palpi represented by long styli with fused basal palpomeres, by metathoracic wings without crossveins and tarsal formula of 5-5-4. Neorrhipidius seicherti sp. n. differs from Quasipirhidius luzziae sp. n. by the presence of postocular ommatidia and by the shape of metascutellum. The distribution of fossil and extant Ripidiinae in Central America is briefly discussed. Furthermore, the frequent occurrence of Quasipirhidius luzziae sp. n. in amber as syninclusions suggests possibly unique synchronisation of emergence unknown in extant taxa or more likely intraspecific aggregative behaviour by males prior to mating with receptive females. and Jan Batelka, Michael S. Engel, Zachary H. Falin, Jakub Prokop.
Two closely related parasitoid wasp species with different host specificities were used for experimental studies on the biology of host finding, a crucial element of parasitoid life history: The habitat and host specialist Nasonia vitripennis and the habitat and host generalist Dibrachys microgastri (Chalcidoidea: Pteromalidae). The host finding parameters tested included reaction to olfactory cues, aspects of locomotor activity, ability to locate hidden hosts and day-night-activity. The results revealed distinct interspecific differences that match the respective host and habitat ranges of the two species. In N. vitripennis host finding is dominated by olfactory reaction to hosts and host habitat, i.e., fly puparia and birds' nests. In D. microgastri olfactory cues have only a minor role. Its host finding is characterized by rapid searching at random. Both species are able to locate hidden hosts. Although still incomplete, these insights into host finding by two parasitoid species with different life history strategies indicate they can be characterized by specific combinations of behavioural host finding features. and Ralph S. Peters.