Isolation and characterization of microsatellite loci in the saltmarsh beetle Pogonus chalceus (Coleoptera,Carabidae)

Five microsatellite loci were isolated from the saltmarsh beetle Pogonus chalceus. Polymorphism ranges from six to 16 alleles, and observed and expected heterozygosities range from 0.437–0.764 and 0.588–0.786, respectively. Most loci cross‐amplified well in four other Pogonus species.     

基于微卫星标记的中国枣食芽象甲地理种群遗传多样性分析

【目的】枣食芽象甲Scythropus yasumatsui是我国北方枣树Zizyphus jujuba上的一种重要的灾害性害虫,在陕西、山西、河北、河南等枣树主产区普遍发生。本研究旨在揭示我国枣食芽象甲不同种群间的遗传分化和基因交流规律。【方法】利用枣食芽象甲转录组测序的SSR序列,使用荧光标记PCR及毛细管电泳分型方法,筛选出8个微卫星位点,对我国5个省份(山西、陕西、宁夏、河北和河南)10个地理种群共308头枣食芽象甲样本进行种群遗传多样性分析。【结果】8个SSR位点均存在无效等位基因且偏离哈迪 温伯格平衡。各位点的有效等位基因数(Ne)为2.113~8.016,多态信息含量(PIC)为0.561~0.908,期望杂合度(He)为0.476~0.865;种群间遗传分化系数(Fst)平均值为0.151;基因流(Nm)平均值为1.594。枣食芽象甲种群间遗传分化系数与地理距离之间显著正相关(r=0.596, P=0.0035),基于Nei’s遗传距离和Cavalli-Sforza & Edwards余弦遗传距离的系统进化树将10个地理种群均聚为3个相同的分支。【结论】结果说明,枣食芽象甲种群遗传多样性较高,不同地理种群间存在高度的遗传分化,且有一定的基因交流;地理隔离是影响枣食芽象甲地理种群遗传分化和基因交流的重要因素。     

An apposition‐like compound eye with a layered rhabdom in the small diving beetle Agabus japonicus (Coleoptera,Dytiscidae)

The fine structure of the compound eyes of the adult diving beetle Agabus japonicus is described with light, scanning, and transmission electron microscopy. The eye of A. japonicus is mango‐shaped and consists of about 985 ommatidia. Each ommatidium is composed of a corneal facet lens, an eucone type of crystalline cone, a fused layered rhabdom with a basal rhabdomere, seven retinula cells (including six distal cells and one basal cell), two primary pigment cells and an undetermined number of secondary pigment cells that are restricted to the distalmost region of the eye. A clear‐zone, separating dioptric apparatus from photoreceptive structures, is not developed and the eye thus resembles an apposition eye. The cross‐sectional areas of the rhabdoms are relatively large indicative of enhanced light‐sensitivity. The distal and central region of the rhabdom is layered with interdigitating microvilli suggesting polarization sensitivity. According to the features mentioned above, we suggest that 1) the eye, seemingly of the apposition type, occurs in a taxon for which the clear‐zone (superposition) eye is characteristic; 2) the eye possesses adaptations to function in a dim‐light environment; 3) the eye may be sensitive to underwater polarized light or linearly water‐reflected polarized light. J. Morphol. 275:1273–1283, 2014. © 2014 Wiley Periodicals, Inc.     

Predaceous diving beetles (Coleoptera: Dytiscidae) of Jordan

The first account of the predaceous diving beetles or Dytiscidae of Jordan is presented. Altogether 25 species are listed, although the occurrence of two of them remains doubtful. Nine species are recorded from the territory of Jordan for the first time, and the first precise locality data are provided for an additional seven species. Bidessus anatolicus Wewalka, 1972 and Nebrioporus stearinus (Kolenati, 1845) recorded recently from Jordan based on misidentification are removed from the list. If available, habitat information is provided for recently collected species. The zoogeographical patterns of the region are briefly summarised.     

Isolation and characterization of microsatellite loci in the ground beetle Carabus problematicus (Coleoptera,Carabidae)

Six microsatellite loci were isolated from the ground beetle Carabus problematicus. The polymorphism ranged from two to 17 alleles and observed and expected heterozygosities ranged from 0.137 to 0.676 and 0.147 to 0.710, respectively.     

Isolation and characterization of microsatellite loci in the ground beetle Carabus nemoralis (Coleoptera,Carabidae)

We isolated and characterized 10 microsatellite loci in the ground beetle Carabus nemoralis (Coleoptera, Carabidae), an ubiquist species largely distributed in Europe. Polymorphism ranged from 3 to 12 alleles on the 30 individuals from the same locality examined.     

Five microsatellite DNA markers for the ground beetle Abax parallelepipedus (Coleoptera,Carabidae)

We characterized five microsatellite loci from Abax parallelepipedus, one of the most common forest ground beetles in central Europe. The polymorphism of the loci was assessed in 30 individuals from one population. The number of alleles ranged between two and 19 and the observed heterozygosities between 0.10 and 0.97. No deviations from Hardy–Weinberg equilibrium were detected for any of the markers.     

Isolation and characterization of polymorphic microsatellite loci in Acanthoscelides obtectus Say (Coleoptera: Bruchidae)

Six microsatellite loci were isolated from the bruchid Acanthoscelides obtectus Say (Coleoptera: Bruchidae). Each locus was polymorphic, with the number of alleles ranging from 3 to 18. We found high levels of within‐population variation at most loci, with heterozygosities ranging from 0 to 0.75. Cross‐species amplification of these loci was tested in two other species of the genus Acanthoscelides, A. obvelatus Bridwell and A. argillaceus Sharp.     

Development of nuclear microsatellite markers for the threatened wetland plant Geranium soboliferum var. kiusianum (Geraniaceae)

Nuclear microsatellite markers were developed for the threatened plant Geranium soboliferum var. kiusianum, which has decreased its population size as a result of loss of its wetland habitat in Kyushu, Japan. Utilizing RNA‐seq data obtained by next‐generation sequencing techniques, 10 polymorphic microsatellite markers with 3–16 alleles in a nuclear genome were developed and characterized. Two to 15 alleles were observed in G. soboliferum. These markers will be used to investigate the genetic circumstance of remnant populations of G. soboliferum var. kiusianum and their phylogenetic relationship with G. soboliferum.     

Development and characterization of 33 polymorphic microsatellite markers in Trachurus japonicus by SLAF-seq technology

Trachurus japonicus is an economically important fish in the northwestern Pacific Ocean. However, its resources have declined seriously and there is an urgent need for a wide-range of investigations of the existing genetic resources. This requires a large number of diverse molecular markers with high discriminating power. In this study, we identified 43,264 perfect SSRs in T. japonicus genome using SLAF-seq technology. Of these, we randomly selected 106 SSRs (tri-nucleotide to hexa-nucleotide) to test for polymorphism. Eventually, we successfully developed a total of 33 loci including 8 tri-nucleotide and 25 long repeat motifs (tetra-nucleotide to hexa-nucleotide). The number of alleles (Na) of these loci ranged from 4 to 24 (mean 12.6). The observed heterozygosity (Ho) and expected heterozygosity (He) varied from 0.258 to 0.969 (mean 0.723) and from 0.452 to 0.962 (mean 0.827), respectively. All loci except TJ6-7 were highly informative (PIC > 0.5). These results showed that the shortlisted 33 loci exhibited moderate to relatively high genetic diversity, of which 18 were regarded as highly polymorphic and well-resolved. In summary, these diverse and potential microsatellites detected in our study provide substantial genetic basis for the screening of polymorphic SSR markers of T. japonicus and also provide a powerful tool to perform further studies on the genetic resource assessment and conservation of T. japonicus.     

Field observation of predation on a horsehair worm (Gordioida: Chordodidae) by a diving beetle larva Cybister brevis Aubé (Coleoptera: Dytiscidae)

Diving beetles (Coleoptera: Dytiscidae) are carnivorous in both the larval and adult stages; larvae are exclusively predatory, whereas adults also scavenge for food. They are known to prey on zooplankton, insects, gastropods, fish, amphibians and reptiles. However, there have been no previous reports detailing direct predation on adult Gordioida by Dytiscidae in the field. This study represents the first observation of a diving beetle larva, Cybister brevis Aubé (Coleoptera: Dytiscidae), predating on an adult horsehair worm (Gordioida: Chordodidae). This might be the first report of predation on horsehair worms by insects.     

Isolation and development of microsatellite markers for the Japanese dormouse, Glirulus japonicus

Eight microsatellite markers were developed for the Japanese dormouse (Glirulus japonicus), a natural monument and near‐threatened species in Japan. The markers amplify in individuals from all of the mitochondrial lineages detected in a previous study. Numerous polymorphisms were detected in specimens from a local population in central Honshu (11–21 alleles per locus; n = 31) and from the entire distribution range of the species (19–41 alleles per locus; n = 152). These microsatellites will be useful in conservation genetic studies of G. japonicus.     

Development and characterization of microsatellite markers in Tectona grandis (Linn. f)

Teak (Tectona grandis Linn. f) is a hardwood species of worldwide reputation. It occurs naturally in India, Thailand, Myanmar and Laos. Fifteen highly polymorphic microsatellite loci were developed from a genomic library enriched for AG/TC repeats. Primers to amplify these loci were tested on 265 individual trees from different teak populations. An average of 14.7 alleles per locus were detected and expected heterozygosity ranged from 0.223 to 0.879. These loci constitute a powerful tool in investigating the mating system, gene flow, parentage analysis and population dynamics for use in sustainable management of teak forests and for in situ conservation purposes.     

Development and characterization of microsatellite markers for a monoecious Ficus species,Ficus insipida,and cross‐species amplification among different sections of Ficus

The animal‐mediated pollination and seed‐dispersal mutualisms of Ficus species give them key roles in tropical ecosystems, but may make them vulnerable to habitat fragmentation. The development of highly polymorphic markers is needed to analyse their genetic diversity and investigate the effects of fragmentation on gene flow. Of thirteen microsatellite loci isolated from Ficus insipida, a monoecious species in French Guiana, eleven were polymorphic (two to six alleles each). High levels of variation were found among loci; expected heterozygosities ranged from 0.151 to 0.715. All markers revealed a broad cross‐species affinity when tested in 23 other Ficus species.     

Isolation and characterization of microsatellite markers for Araucaria angustifolia (Araucariaceae)

Araucaria angustifolia is a dioecious tree species that occurs in the southern part of Brazil. Because of the intense exploitation of the species due to its valuable wood, only 2% of the original population still remains. Twenty‐nine species‐specific and highly polymorphic microsatellite loci were developed from a genomic library enriched for AG/TC repeats. Levels of polymorphism were evaluated using a total of 16 adult trees from a natural population. An average of 8.1 alleles per locus was detected, and expected heterozygosity ranged from 0.63 to 0.72.     

Isolation and characterization of polymorphic microsatellite loci from Brandt's voles (Lasiopodomys brandtii)

Ten polymorphic microsatellite loci from Lasiopodomys brandtii have been isolated and characterized. Two to 11 alleles per locus were detected from 52 Brandt's voles samples collected from a single population. Expected heterozygosities ranged from 0.406 to 0.840. For the majority of loci observed heterozygosities were similar to or greater than the expected heterozygosity. One locus pair appeared to be in linkage disequilibrium. The microsatellite markers will enable the studies of genetic diversity, population structure and relatedness in this species, and perhaps in closely related species of vole.     

Speciation of Iberian diving beetles in Pleistocene refugia (Coleoptera, Dytiscidae)

The Mediterranean basin is an area of high diversity and endemicity, but the age and origin of its fauna are still largely unknown. Here we use species-level phylogenies based on approximately 1300 base pairs of the genes 16S rRNA and cytochrome oxidase I to establish the relationships of 27 of the 34 endemic Iberian species of diving beetles in the family Dytiscidae, and to investigate their level of divergence. Using a molecular clock approach, 18-19 of these species were estimated to be of Pleistocene origin, with four to six of them from the Late Pleistocene ( approximately 100 000 years). A second, lower speciation frequency peak was assigned to Late Miocene or Early Pliocene. Analysis of the distributional ranges showed that endemic species placed in the tip nodes of the trees are significantly more likely to be allopatric with their sisters than endemic species at lower node levels. Allopatric sister species are also significantly younger than sympatric clades, in agreement with an allopatric mode of speciation and limited subsequent range movement. These results strongly suggest that for some taxa Iberian populations were isolated during the Pleistocene long enough to speciate, and apparently did not expand their ranges to recolonize areas north of the Pyrenees. This is in contradiction to observations from fossil beetles in areas further north, which document large range movements associated with the Pleistocene glacial cycles hypothesized to suppress population isolation and allopatric speciation.     

Development of microsatellite markers in heterostylous Hedyotis chrysotricha (Rubiaceae)

? Premise of the study: Microsatellite primers were developed for a heterostylous herb, Hedyotis chrysotricha to investigate the effect of habitat fragmentation on its genetic diversity and population structure. ? Methods and Results: Twelve primer sets were developed and their polymorphisms were tested on 47 individuals from two island populations of H. chrysotricha in Thousand Island Lake of China. The number of alleles per locus ranged from five to 10, with an average of seven alleles. Expected heterozygosity per locus ranged from 0.284 to 0.821 and observed heterozygosity ranged from 0.191 to 0.851. ? Conclusions: We showed that all of the 12 microsatellite markers developed for H. chrysotricha are polymorphic within populations, which should provide a powerful tool for assessing population structure and genetic diversity across fragmented and continuous populations, and for studying the genetic effects of habitat fragmentation on this species.