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This study aims to infer the proportion of queens and workers of the hornet Vespa analis parasitized by the strepsipterous parasite Xenos moutoni in overwintered females from morphological data collected for three years. It is known that both worker and queen hornets parasitized by strepsipterous insects overwinter. The parasitized queens cannot reproduce in the next season and thus the level of parasitism potentially affects the number of colonies to be established in the population. Thus, estimation of the ratio of parasitized queens to the total of parasitized females would he useful for understanding the population dynamics of the hornet. K-means cluster analysis demonstrated that 50 to 85% of individuals were workers in the total of parasitized females during the period. From 8 to 15% of total queens were thought to be sterilized by X. moutoni, a level that would not be expected to have a serious effect on the population dynamics of V. analis. Forced hibernation of workers might be considered to be a result of manipulation of the diapause system of the host by the parasite to increase its reproductive success. [ABSTRACT FROM AUTHOR]

We isolated eight polymorphic microsatellite loci from the zooplankton Moina macrocopa (Straus), which is sensitive to pollutants such as insecticides and heavy metals. The isolated loci were polymorphic, with three to seven alleles among 23 individuals. Expected heterozygosities ranged from 0.167 to 0.787. These loci can be used to examine cryptic genetic structure and to infer the connectivity among metapopulations. [ABSTRACT FROM AUTHOR]

We revised the fauna of goblin spiders (Oonopidae) in the Nansei Islands, southwest Japan, and recognized 12 species of seven genera. Eleven of them were described species, namely, Gamasomorpha cataphracta Karsch, 1881, Heteroonops spinimanus (Simon, 1892), Ischnothyreus narutomii (Nakatsudi, 1942), Ischnothyreus peltifer (Simon, 1891), Ischnothyreus velox Jackson, 1908, Opopaea cornuta Yin & Wang, 1984, Opopaea deserticola Simon, 1892, Opopaea syarakui (Komatsu, 1967), Orchestina flava Ono, 2005, Xestaspis parmata (Thorell, 1890), and Xyphinus karschi (Bsenberg & Strand, 1906). A new species is described under the name of Ischnothyreus ogatai sp. nov. This paper provides photographs of each oonopid species, notes on habitat and distribution, and keys to the species. A detailed description of I. ogatai sp. nov. (for both sexes), morphological data regarding three species newly added to the Japanese fauna (X. parmata, I. velox, and O. cornata), and additional data on the genital morphology of G. cataphracta are also presented.

Global commerce and transportation facilitate the spread of invasive species. The African big-headed ant, Pheidole megacephala (Fabricius), has achieved worldwide distribution through globalization. Since the late 19th century, Taiwan has served as a major seaport because of its strategic location. The population genetic structure of P. megacephala in Taiwan is likely to be shaped by international trade and migration between neighboring islands. In this study, we investigated the population genetics of P. megacephala colonies sampled from four geographical regions in Taiwan and elucidated the population genetic structures of P. megacephala sampled from Taiwan, Okinawa, and Hawaii. We observed a low genetic diversity of P. megacephala across regions in Taiwan. Moreover, we noted low regional genetic differentiation and did not observe isolation by distance, implying that long-distance jump dispersal might have played a crucial role in the spread of P. megacephala . We sequenced the partial cytochrome oxidase I gene and observed three mitochondrial haplotypes (TW1-TW3). TW1 and TW3 most likely originated from populations within the species' known invasive range, suggesting that secondary introduction is the predominant mode of introduction for this invasive ant. TW2 represents a novel haplotype that was previously unreported in other regions. P. megacephala populations from Taiwan, Okinawa, and Hawaii exhibited remarkable genetic similarity, which may reflect their relative geographic proximity and the historical connectedness of the Asia-Pacific region., Competing Interests: The authors declare no competing financial interests., (© 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

The cytogenetic characteristics of the grasshopper Podisma sapporensis (two races 2n = 23♂ X0/XX and 2n = 22♂ neo-XY/neo-XX) were analysed through fluorescence in situ hybridization with rDNA and telomeric DNA probes, C-banding, fluorochrome and silver staining. For the first time, samples from the neighbourhood of a hybrid population (i.e., Mikuni Pass population) were studied. Our results indicated a significant degree of chromosomal differentiation between P. sapporensis races when comparing the number and position of the rDNA sites, as well as the heterochromatin composition and distribution obtained by C-banding and DAPI/CMA 3 staining. Telomeric signals were usually detected at the distal and/or subdistal position of the autosomes; however, some chromosome ends lacked signals, probably due to a low number of telomeric repeats. On the other hand, telomeric DNA sequences were found as interstitial telomeric repeats in some autosomes, which can trigger a variety of genome instability. B chromosomes were found in specimens belonging to both main races from nine out of 22 localities. Four types of X chromosomes in the X0/XX race were identified. It was concluded that the physical mapping of rDNA sequences and heterochromatin are useful as additional markers for understanding the phylogeographic patterns of cytogenetic differentiation in P. sapporensis populations.