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Three new species, Halyzia ichiyanagii sp. nov., Vibidia fukudai sp. nov., and Vibidia saitoi sp. nov. are described, illustrated and compared. Scymnus (Neopullus) yotsuhoshi Kitano, 2012 is newly transferred to the nominotypical subgenus of Scymnus Kugelann, 1794. [ABSTRACT FROM AUTHOR]

Differences in the time of occurrence of both sexes of adult ladybirds, which reflect differences in the longevity and reproductive strategies of the sexes, is important from the perspective of applied entomology, including biological control, as well as basic entomology. Nevertheless, there is little field census data on this topic. We investigated the seasonal occurrence of both sexes of Cheilomenes sexmaculata (Fabricius) in Osaka City, central Japan, from 2003 to 2011. Female adults tended to appear earlier than males after hibernation or aestivation. That males never appeared earlier than females during the nine year period of this study indicate that protogyny occurs after hibernation and aestivation in this species. [ABSTRACT FROM AUTHOR]

[Display omitted] • Five species were highly attracted to 385 and 405 nm wavelengths. • Aphidius colemani responded differently depending on mating status. • LED lighting strategy can be used to attract or manipulate many natural enemies. Recently, the positive phototaxis exhibited by natural enemies such as Nesidiocoris tenuis (Hemiptera: Miridae) and Orius sauteri (Hemiptera: Anthocoridae) has been explored to enhance pest control efficiency in agriculture, mainly in Korea and Japan. Here, we evaluated the responses of seven natural enemies: Aphidius colemani , Asobara japonica (Hymenoptera: Braconidae), Chrysoperla carnea (Neuroptera: Chrysopidae), Harmonia axyridis , Illeis koebelei (Coleoptera: Coccinellidae), Nabis stenoferus (Hemiptera: Nabidae), and O. minutus (Hemiptera: Anthocoridae), to different wavelengths of LED light (i.e., 385, 405, 450, and 660 nm) to clarify the potential of phototaxis for behavioral manipulation of natural enemies. Also, we assessed how mating status and gender affected the responses of A. colemani and O. minutus using a video tracking system, EthoVision ® XT. Overall, wavelengths of 385 and 405 nm were highly attractive to natural enemies, except for C. carnea and N. stenoferus. Unmated females of A. colemani moved greater distances than mated ones, the latter remaining significantly longer in the zone illuminated with UV light compared to the zone illuminated with white light. Adult O. minutus of both sexes remained longer under UV light than under white light. Therefore, the use of UV or near-UV lighting should serve to increase the retention time of natural enemies near light sources and might be useful to retain these and other natural enemies in specific agricultural contexts for better control of pests. [ABSTRACT FROM AUTHOR]

The ladybird beetle, Cheilomenes sexmaculata (Fabricius), has been extending its distribution in and around urban areas at higher latitudes in Japan over the past 100 years. Between 2003 and 2011, we investigated the seasonal occurrence, aphid prey and population dynamics of this species in an urban park in Osaka City, central Japan. We found that C. sexmaculata completes three generations a year in Osaka. Overwintered adults emerge in March or April and produce two (or rarely one) generations by summer. Second-generation adults aestivate and subsequently produce another generation in autumn. This species feeds on five species of aphids that infest planted shrubs and alien weeds throughout the vegetative season. We analyzed the association between accumulated temperature and when overwintered adults first emerged. In addition, we determined the association between their time of emergence, peak abundance and last occurrence, and meteorological conditions. There was no association between the sum of effective temperatures and termination of adult overwintering. There was, however, an association between first occurrence and peak abundance, and climatic conditions, such as warm temperatures or low humidity. This species maintained a stable population in an urban park by becoming quiescent when climatic conditions were unfavourable or prey was scarce. We discussed these findings in relation to urban environmental factors, such as climate, food conditions and vegetation. [ABSTRACT FROM AUTHOR]

1. Resource competition and intra-guild predation (IGP) are important determinants of the structure of aphidophagous guilds. The likelihood and outcome of IGP is influenced by the density of extra-guild prey and the characteristics of the species involved. 2. The nature of intra-guild interactions between alien and indigenous coccinellids often determines the success of coccinellid invasions, as exemplified by Adalia bipunctata in Japan and Harmonia axyridis in North America and Europe. 3. Harmonia axyridis has negatively impinged on indigenous species in its introduced range, and its recent arrival in Britain poses a threat for members of native aphidophagous guilds. IGP and inter-specific competition between H. axyridis and British coccinellids are predicted to occur. However, the results of such interactions have been little studied. 4. Here we investigate the effects of different diets, designed to mimic possible conditions in the wild, on the survival, development, and adult size of H. axyridis and A. bipunctata. Results demonstrate a skew in the consequences of IGP between the two species: the supplementation of a limited aphid diet with non-conspecific eggs leads to a significant advantage for H. axyridis in respect of all parameters assessed, but gives no benefit to A. bipunctata. 5. We conclude that IGP of A. bipunctata by H. axyridis will contribute to the spread and increase of H. axyridis in Britain. 6. We further conclude that the skewed nature of IGP between A. bipunctata and H. axyridis at least in part explains the limited spread of A. bipunctata in Japan. [ABSTRACT FROM AUTHOR]

The sibling species H. yedoensis Takizawa coexists sympatrically and simultaneously with H. axyridis only on pine trees in Japan. To elucidate the mechanisms enabling coexistence of these two sympatric sibling species, a laboratory experiment was performed that focused on differences in their maternal investment through eggs and the role of sibling cannibalism. The egg size (volume) of H. yedoensis was 24.91% larger than that of H. axyridis. Cluster size in H. axyridis was significantly larger than that in H. yedoensis; however, the total number of eggs and oviposition cost (by volume) per female in H. yedoensis were not significantly different from those in H. axyridis, although total number of clusters tended to be slightly higher in H. yedoensis than in H. axyridis. The percentage of undeveloped eggs per cluster in H. yedoensis was not significantly different from that in H. axyridis, whereas the percentage of developed eggs with delayed hatching per cluster was significantly larger in H. yedoensis than in H. axyridis. Moreover, the cost of sibling cannibalism per hatched larval cluster in H. yedoensis (worth 4.43 sibling eggs) was 3.36 times larger than that in H. axyridis.Therefore, maternal investment through egg and sibling cannibalism in developed eggs with delayed hatching are more intense in H. yedoensis than in H. axyridis, implying a higher larval survival rate through higher ability of prey capturing at the first instar. The results in this study suggest that the higher survival rate and accelerated development in H. yedoensis by the two maternal investments, i.e., a large egg and intense sibling cannibalism of developed eggs with delayed hatching, may play an important role in sympatric coexistence with the aggressive aphidophagous ladybird beetle H. axyridis. [ABSTRACT FROM AUTHOR]

1. Why some exotic species invade successfully while others do not is poorly understood. This study focuses on the inability of the exotic predatory ladybird Adalia bipunctata (L.) (Coleoptera, Coccinellidae) to establish and spread in Japan. In particular, this study considers the interactions between A. bipunctata and three native Japanese ladybird species, Harmonia axyridis Pallas, Coccinella septempunctata Linn., and Propylea japonica Mulsant. 2. The number of aphids occurring on the host plants declined dramatically over the course of larval development in the presence of H. axyridis or C. septempunctata. In contrast, many aphids remained at the end of the experiment when only A. bipunctata or P. japonica was present. 3. The survivorship of A. bipunctata from second instar to adult was significantly reduced in the presence of H. axyridis, but not in the presence of C. septempunctata or P. japonica. Most deaths were the result of intra-guild predation when H. axyridis or C. septempunctata larvae were present. Larvae of H. axyridis and C. septempunctata suffered very high mortality in this experiment, but survived better when co-occurring with A. bipunctata than when occurring only with conspecifics. In contrast, P. japonica survived better when occurring with conspecifics than with A. bipunctata. 4. The finding that larvae of the exotic species A. bipunctata died at high rates from intra-guild predation by the native Japanese ladybirds H. axyridis and C. septempunctata may bear on the question of why A. bipunctata has not established more successfully in Japan whereas H. axyridis and C. septempunctata have been very successful in establishing themselves in North America. [ABSTRACT FROM AUTHOR]