Male counterstrategy against infanticide of the female giant water bugLethocerus deyrollei (Hemiptera: Belostomatidae)

The male giant water bug'sLethocerus deyrollei counterstrategy against egg mass destruction by the female was investigated in the laboratory. When mature females encounter a brooding male, they destroy his egg mass and thereby take over the mate and gain a nurse for their own egg mass. However, when the male stays on egg masses laid above the water surface, females cannot detect the male nor the egg mass. Eggs of this species fail to hatch without being supplied with water by males. In the observation, brooding males frequently ascend the stick to the egg mass and stay there for long periods, although most of the water attached to their body surface flowed down in 90 s. These long stays on egg masses are regarded as countestrategies against females.     

Egg attendance and brooding by males of the giant water bugLethocerus medius (Guerin) in the field (Heteroptera: Belostomatidae)

Males of the giant water bug Lethocerus medius(Guerin) typify their monobasic subfamily, the Lethocerinae, in that they do not brood eggs attached to their backs as do males of all members of the subfamily Belostomatinae. Exclusive male parental investment as expressed in the Belostomatinae is extremely rare behavior among animals, and evolution of the trait is obscure. Lethocerus mediusmales apparently remain with their mates through oviposition and are consistently found in attendance of eggs after the female has departed. This behavior may enhance paternity assurance at no cost in opportunity for polygyny. Two double clutches of eggs were found, from which we infer the potential for polygynous matings and shared parental investment. Male L. mediusbrood attended egg clutches above the surface of the water, where they may moisten them, shade them, and defend them against predation. Egg attendance/brooding by L. mediusand other Lethocerusspecies may represent a plesiomorphic state from which paternal back- brooding evolved in the Belostomatinae.     

Comparative studies on the seasonal occurrence,nymphal development and food menu in two giant water bugs,Diplonychus japonicus vuillefroy andDiplonychus major esaki (Hemiptera: Belostomatidae)

We compared the seasonal changes in population density and nymphal development at different water temperatures and under different food conditions between two giant water bugs, Diplonychus japonicus and D. major, in Okayama, Japan. D. japonicus produced 1–2 generations a year, while D. major was strictly inivoltine. The developmental velocity was higher in D. japonicus than in D. major. The thermal constant of D. japonicus was less than that of D. major. These results suggest that D. japonicus is adapted, to higher water temperature than D. major. In the field, D. japonicus preyed predominately on Lymnaeidae and Physidae snails, while D. major preyed on aquatic insects such as dragonfly nymphs.     

Paternity analysis in the golden egg bug using AFLPs: do the males preferentially accept their true genetic offspring?

Abstract.  1. The evolution of parental care and intraspecific parasitism involve conflicts of interest between mothers and other potential care givers who contribute to enhance offspring survival. In the golden egg bug, Phyllomorpha laciniata Villers (Heteroptera: Coreidae), females lay eggs on conspecifics and on plants. The adaptive significance of egg carrying in this species has been the subject of some controversy, which can only be resolved by determining the genetic relationship between the eggs and the adult who carries them. This study examined whether male acceptance of true genetic offspring occurs with a higher frequency than that expected from random oviposition on conspecifics.
2. Paternity analysis, using Amplified Fragment Length Polymorphism (AFLP) markers, was conducted on eggs carried by males housed with field-mated females.
3. Out of the total number of eggs sired by males in the experimental groups, the proportion of eggs carried by males that were their true genetic offspring was 30.8%.
4. Monte Carlo methods show that the probability of a male accepting an egg that is his true genetic offspring is higher than expected if females dumped eggs on males at random.
5. These results suggest that paternal care plays an important role in the maintenance of male egg carrying in this species. In addition, the methodology developed may become useful in determining true genetic parents in other species in which neither the father nor the mother can be determined by observational methods.     

Taxonomic review and distribution of giant water bugs (Hemiptera: Belostomatidae: Lethocerinae) in the Palearctic,Oriental, and Australian regions

The aim of the present study was to analyze the morphology and COI sequences of giant water bugs (Belostomatidae: Lethocerinae) that inhabit the Palearctic, Oriental, and Australian regions (i.e., three Lethocerus and a single Kirkaldyia species). Analysis revealed that both L. patruelis and L. indicus share two light stripes on the pronotum, but L. patruelis possesses narrower stripes and L. insulanus possesses an additional longitudinal narrow dark median band, whereas K. deyrolli was characterized by not having such markings. With regards to genetic analysis, the average intraspecific genetic distances of L. patruelis and L. indicus (from Palearctic and Oriental regions are 0.3 and 0.8%, respectively), but K. deyrolli which was collected from Northeast Asia, showed much higher intraspecific genetic distance (3.7%). The genetic distance between Kirkaldyia and Lethocerus (16.4–16.8%) is similar to that found between the genera of other hemipteran taxa. This study also newly reported the extended easternmost distribution of L. patruelis up to Surat Thani Province in southern Thailand. Along with K. deyrolli, which is considered threatened in South Korea and Japan, Lethocerus species have been facing threats in Southeast Asia, where they are heavily harvested and commonly sold in local markets as food. Therefore, future conservation efforts should be directed toward Lethocerus species in tropical Southeast Asia, especially the rarely found L. patruelis.     

Isolation and characterization of microsatellite markers for Viola mirabilis (Violaceae) using a next‐generation sequencing platform

We isolated and characterized microsatellite loci in Viola mirabilis (Violaceae), an endangered species from South Korea. Twenty‐three polymorphic microsatellite loci were developed and tested in Korean, Chinese and Japanese populations. The number of alleles per locus varied from two to eight. The observed and expected heterozygosities within the three populations were 0.000–0.625 and 0.469–0.695, respectively. A total of six loci in the Korean population, one locus in the Chinese population and seven loci in the Japanese population deviated from Hardy–Weinberg equilibrium. We expect that these newly developed microsatellite markers will contribute to understanding the phylogeography and population genetics of V. mirabilis, which will aid in developing conservation strategies for this species.     

Eight polymorphic microsatellite markers developed in the green leaf bug,Lygus lucorum Meyer‐Dür (Hemiptera: Miridae)

We developed eight polymorphic microsatellite markers for the green leaf bug, Lygus lucorum Meyer‐Dür. The number of observed alleles per locus in 48 individuals ranged from three to 13, whereas the observed and expected heterozygosities ranged from 0.133 to 0.810 and from 0.236 to 0.886, respectively. Cross‐species amplifications were conducted both within and between generas, and the amplification results indicated that these primers enriched for L. lucorum Meyer‐Dür are species‐specific.     

Development of microsatellite markers for parentage analysis in the great tinamou (Tinamus major)

Eighteen microsatellite loci were isolated from great tinamous (Tinamus major), which are large terrestrial birds found in the Neotropics. These are the first primers developed for the Order Tinamiformes. Paternity analyses are possible because the levels of heterozygosity are sufficiently high (0.29-0.90).     

New occurrence of the invasive alien leaf‐footed bug Leptoglossus gonagra (Hemiptera: Coreidae) in South Korea

The invasive alien leaf‐footed bug Leptoglossus gonagra (Fabricius 1775), native to the Americas, is herein recorded from South Korea for the first time. Forty nymphs and adults were collected on 22 September 2016 from arable lands of two separate sites. These individuals were identified based on the analysis of morphological characters and cytochrome oxidase c subunit 1 sequences. A neighbor‐joining tree indicated the existence of two clades: Group A from Brazil, and Group B from Asia and Oceania. Mean genetic distance between clades was 8.11%, range 7.60–8.57%. Within clades, mean genetic distance was 0.42% (0.17–0.83%) in Group A and, 0.45% (0.00–0.83%) in Group B. Colonies of 2nd‐final instar nymphs and adults were found, on top of leaves, flowers, fruits, and between the stems of pumpkins (Cucurbita moschata). Nymphs and adults damaged host plants by sucking their leaves, stems, fruits, and buds. After the first discovery in 2016, we were unable to find the bugs again (in 2017–2019). Therefore, the invasion of this species seems to have occurred only temporarily, during the warm season. We suggest that the species may have failed to overwinter as it is normally distributed in regions warmer than Korea. Nevertheless, possible appearances of this species must be continuously monitored as it is a potential pest of various plants cultivated in South Korea.     

Development of microsatellite markers in black locust (Robinia pseudoacacia) using a dual‐supression‐PCR technique

Black locust (Robinia pseudoacacia) is an economically and ecologically important tree species in the world. We isolated seven polymorphic microsatellite loci from R. pseudoacacia using a dual‐suppression‐PCR technique. These loci provided microsatellite markers with high polymorphism ranging from three to 12 alleles per locus and expected heterozygosity between 0.538 and 0.944. The markers are now available for more detailed investigation of population genetic structure and pollen and seed dispersal.     

Factors influencing egg parasitism in sub‐social insects: insights from the treehopper Alchisme grossa (Hemiptera,Auchenorrhyncha, Membracidae)

相似文献   

Isolation and characterization of Ligustrum micranthum (Oleaceae) microsatellite loci using paired‐end Illumina reads

Twenty‐six microsatellite loci were developed and characterized for Ligustrum micranthum, a species endemic to the Ogasawara Islands, Japan. The genetic structure of this species must be clarified in order to restore the island's ecosystem. A total of 8511 primer pairs were designed from de novo sequencing. Of the 48 primer pairs selected, amplification and polymorphisms were tested using one population each from the Chichijima and Hahajima Islands of the Ogasawara Islands. Twenty‐six microsatellite loci were successfully amplified and the number of alleles for these loci ranged from five to 31 per locus, and the mean expected heterozygosities were 0.858 and 0.849, respectively. No significant deviation from the Hardy–Weinberg equilibrium was observed in either population, and no significant linkage disequilibrium was detected between any locus pair. The microsatellite loci reported in this study can be used in future studies to evaluate the genetic structure and mating system of L. micranthum.     

Novel polymorphic microsatellite markers for paternity analysis in the red‐capped robin (Petroica goodenovii: Aves)

Seven microsatellite loci were isolated and characterized from the red‐capped robin Petroica goodenovii, using nonradioactive polymerase chain reaction (PCR)‐based techniques to screen an enriched genomic library. Five loci showed no evidence of null alleles and were variable [mean heterozygosity (H_E) = 0.440, mean number of alleles = 8]. Cross‐amplification using primers for microsatellites in Phylloscopus occipitalis and Emberiza schoeniclus yielded another two polymorphic loci. The combined set of five red‐capped robin and two cross‐amplified loci are suitable for paternity assignment (exclusion probability for seven unlinked loci = 0.9760).     

Influence of non‐crop plants on stink bug (Hemiptera: Pentatomidae) and natural enemy abundance in tomatoes

We investigated the effects of weed hosts on stink bug density and damage (Euschistus conspersus Uhler and Thyanta pallidovirens Stal), and a nectar bearing plant on natural enemies of stink bugs in the Sacramento Valley of California. Stink bug density and fruit damage were evaluated in processing tomatoes adjacent to weedy and cultivated borders. The density of E. conspersus was significantly greater in tomatoes adjacent to weedy borders in July but not during August/September. Thyanta pallidovirens was less abundant overall (19%), but was found in significantly greater densities adjacent to cultivated borders in July but not in August/September. Mean percent fruit damage by stink bugs was greater adjacent to the weedy border than the cultivated border, but this difference was not significant. Stink bug egg parasitism and generalist predator density were evaluated in fresh market tomatoes adjacent to a sweet alyssum (Lobularia maritima L.) border and an unplanted control border at three sites. Egg parasitism was significantly greater in the alyssum treatment for the 9–12 September sampling period. Jalysus wickhami VanDuzee (Hemiptera: Berytidae) density was significantly greater in the alyssum treatment in mid‐June. No other significant differences in predator populations were detected. Results of these two studies show that habitat manipulations have the potential to reduce densities of E. conspersus in tomato, the first step in developing a farmscape management plan for stink bug control.     

Genetic diversity of Ligula intestinalis (Cestoda: Diphyllobothriidea) based on analysis of inter‐simple sequence repeat markers

In order to investigate the genetic diversity of Ligula intestinalis populations, nine inter‐simple sequence repeat (ISSR) markers were applied to populations from nine geographical areas around the world and 10 host species. The 110 loci selected from the ISSR patterns produced revealed high variability among the analysed samples, with a polymorphism of 100% and a global coefficient of gene differentiation estimated by Nei’s index (G_ST) of 0.776. Major genetic differentiation was found to be correlated to five broad geographical regions (Europe, China, Canada, Australia and Algeria). Nevertheless, no significant genetic variation was found among European isolates, although they originated from disparate geographical localities and/or unrelated hosts. Classical classification methods: maximum parsimony and factorial correspondence analysis were compared with an advanced statistical method: the self‐organizing map (SOM). The results demonstrated that the ISSR approach is rapid and inexpensive and provides reliable markers to assess genetic diversity of L. intestinalis. Furthermore, SOM artificial neuronal networks are considered to provide an efficient alternative tool for mapping the genetic structures of parasite populations.     

Characterization of polymorphic microsatellite DNA markers in the black-tailed godwit (Limosa limosa: Aves)

We isolated and tested 16 microsatellite loci in black-tailed godwits from the Netherlands (Limosa limosa limosa), and from Australasia (subspecies melanuroides). One locus was monomorphic, two loci had null-alleles and one was significantly heterozygote deficient. The remaining 12 polymorphic loci had on average 7.9 alleles (range 5-11) and the mean expected heterozygosity was 0.69. No significant linkage disequilibrium between the loci was observed and all loci were autosomal. Fourteen loci were successfully cross-amplified in bar-tailed godwit (Limosa lapponica).     

Isolation and characterization of microsatellite markers in the southern emu‐wren (Stipiturus malachurus: Aves)

We isolated and characterized eight novel microsatellite loci in the southern emu‐wren (Stipiturus malachurus). We used nonradioactive polymerase chain reaction (PCR)‐based techniques to screen an enriched genomic DNA library. Based on genotypes from a single population, six loci showed no evidence of null alleles and were polymorphic (allele range = 2–9, mean heterozygosity = 0.57), and one locus was sex‐linked (N_A = 4). These loci were variable and had different allele size ranges in three other populations of southern emu‐wrens, and are therefore useful for determining levels of genetic diversity within and between populations of the species.     

Di‐ and tetranucleotide microsatellite markers for the Alpine newt (Triturus alpestris): characterization and cross‐priming in five congeners

We developed a set of di‐ and tetranucleotide microsatellite markers for the Alpine newt, Triturus alpestris. Polymorphism as detected in 39 individuals ranged from 3 to 32 alleles at a locus. Cross‐priming with samples of five other Triturus species showed extremely poor levels of cross‐species utility. Still, these markers are suitable for studies of inter‐ and intrapopulation genetic diversity in the focal species.     

The paternal‐sex‐ratio (PSR) chromosome in natural populations of Nasonia (Hymenoptera: Chalcidoidea)

Selfish genetic elements may be important in promoting evolutionary change. Paternal sex ratio (PSR) is a selfish B chromosome that causes all‐male families in the haplodiploid parasitic wasp Nasonia vitripennis, by inducing paternal genome loss in fertilized eggs. The natural distribution and frequency of this chromosome in North American populations of N. vitripennis was investigated using a combination of phenotypic and molecular assays. Sampling throughout North America failed to recover PSR except from populations in the Great Basin area of western North America. Extensive sampling of Great Basin populations revealed PSR in frequencies ranging from 0 to 6% at different collection sites, and extended its distribution to Idaho and Wyoming. Intensive sampling in upstate New York did not detect the chromosome. Frequencies of the maternal‐sex ratio distorter (MSR), son killer (SK) and virgin females ranged from 0 to 12%. Paternal sex ratio may be restricted to the Great Basin because its spread is hampered by geographical barriers, or because populations in other areas are not conducive to PSR maintenance. However, it cannot be ruled out that PSR occurs in other regions at very low frequencies. The apparent limited distribution and low frequency of PSR suggest that it will have relatively little impact on genome evolution in Nasonia.