Haplotype diversity and distribution pattern of Oecophylla smaragdina (Fabricius) (Hymenoptera,Formicidae) in Bangladesh based on mitochondrial COI genes

Climatic oscillation often have influenced the present distribution and intraspecific genetic diversity Oecophylla smaragdina through its wide range of geographical distribution. Previous phylogeographic study of Asian weaver ant population denotes the evidence of distribution of Indian types in Indian, Sri Lanka and SE Asian types in South Asian countries including Bangladesh. However, recent phylogenetic analysis reveals the overlapping distribution of the Indian and South East Asian clades of O. smaragdina in Bangladesh. The present study aims to identify the haplotypes and it’s networking in Bangladesh based on extensive materials. Sampling was executed according to zonation of 5 areas, demarcated by 3 main rivers during the years 2013 to 2018. Adult O. smaragadina workers were collected from 71 colonies of 67 localities belonging to 47 districts of Bangladesh. A total of 25 haplotypes were identified in Bangladesh comprises 13 and 12 of Indian and SE Asian types, respectively from 93 sequences of Cytochrome c oxidase subunit I (COI) gene of 639 bp. The geographical distribution of this haplotype reveals that the Indian haplotypes are mostly located at the western part of Bangladesh while SE Asian haplotypes were dominated in the Eastern part of the country. Central part of Bangladesh has overlapped with the mixture of both Indian and SE Asian haplotypes. The results of the haplotype network give the evidence of recent expansion of O. smaragdina population in Bangladesh and clarify the evidence of presence of many missing haplotypes in refugee.     

Italian Peninsula preserves an evolutionary lineage of the fat dormouse Glis glis L. (Rodentia: Gliridae)

The present study examines the population genetic structure of fifty‐nine specimens of Glis glis (Linneaus, 1766) from thirteen localities in central Europe, sequencing a 400‐bp segment of the mitochondrial cytochrome b (cyt b) gene and a 673‐bp segment of the cytochrome c oxidase subunit I (COI) gene. The consensus tree obtained from Bayesian analysis revealed a robust dichotomy, showing two sister groups: one clade includes samples from a wide geographical area, extending from north‐central Europe to northern Italy (major branch sensu Bilton), and the other comprises samples collected in central and southern Italy and in Sicily (Italian branch). According to the Tajima–Nei model, the two phylogroups were separated by a sequence divergence of 0.8% (cyt b) – 2.6% (COI), showing the COI gene to be more informative than cyt b. On a smaller geographical scale, the Italian clade was further substructured, displaying geographical differentiation along the Peninsula. The gene pool in this area was patchy; whereas populations from Sicily Island demonstrated fixed cyt b and COI haplotypes, assuming processes of isolation and selection. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102 , 11–21.     

Observations on the Ecology of Weaver Ants (Oecophylla smaragdina Fabricius) in a Thai Mangrove Ecosystem and Their Effect on Herbivory of Rhizophora mucronata Lam.

Ants of the genus Oecophylla are predators of other insects and are able to protect a variety of terrestrial plants against pest insects; however, observations on the ecology of these ants in mangrove forests are lacking. General observations on the ecology of Oecophylla smaragdina were carried out in a Thai mangrove forest to determine if these ants can protect their host plants in less favorable mangrove habitats. Leaf herbivory and the density of O. smaragdina ants were measured on Rhizophora mucronata trees at two sites. The results showed a negative correlation between ant density and herbivory. At both sites, the mean percent damaged leaf area was more than four times higher on trees without ants compared to “ant‐trees.” A significant negative correlation was found between tree mean percent leaf damage and the density of ants on the tree. Furthermore, on trees with ants, there was less herbivory on leaves close to ant nests compared to other leaves on the tree. Most damage was caused by chrysomelid beetles (62%) and sesarmid crabs (25%) and both types of herbivory were significantly reduced on ant‐trees.     

Are invasive ants better plant‐defense mutualists? A comparison of foliage patrolling and herbivory in sites with invasive yellow crazy ants and native weaver ants

Benefits arising from facultative mutualisms between ants and plants vary with the identity of the ant partner. Invasive and native ants are both attracted to plants that offer extrafloral nectar, but few studies have compared their abilities to displace herbivores and benefit plants. Yellow crazy ants Anoplolepis gracilipes have invaded eucalypt woodlands of Arnhem Land, northern Australia, where they displace the native dominant weaver ant Oecophylla smaragdina. We compared the plant defense services provided by A. gracilipes and O. smaragdina ants on trees with (Acacia lamprocarpa) and without (Eucalyptus tetrodonta) extrafloral nectar rewards through surrogate herbivore (termite) addition experiments and surveys of herbivore damage. Anoplolepis gracilipes were more likely than O. smaragdina to discover termites on A. lamprocarpa, but the likelihood of termite discovery on E. tetrodonta did not vary with ant species. Anoplolepis gracilipes were also more thorough in their attacks of termites, recruited 3.4–4 times more workers to termites, and were 3.4 times quicker at discovering termites on A. lamprocarpa than were O. smaragdina. Discovery of termites by other predators did not vary significantly between trees in A. gracilipes and O. smaragdina sites. Herbivory scores did not reflect the foliage patrolling pattern by the ants. Old A. lamprocarpa leaves and both new and old leaves and branches on E. tetrodonta in A. gracilipes sites had higher chewing herbivory scores than their counterparts in O. smaragdina sites. Our results reveal that the more aggressive and efficient foliar patrolling by A. gracilipes does not translate to increased plant protection. Ant invasions can disrupt native ant–plant mutualisms despite invasive ants possessing many traits associated with effective plant guarding.     

基于线粒体基因Cytb和COI的蝗科中五亚科分子系统发育关系分析（直翅目: 蝗总科）（英文）

本研究基于Cytb 基因和COI基因的部分序列来推断17种蝗虫之间的系统发育关系。这17种蝗虫均采自国内,代表了蝗科(Acrididae)5个亚科：黑蝗亚科(Melanoplinae)、斑腿蝗亚科(Catantopinae)、刺胸蝗亚科(Cyrtacanthacridinae)、斑翅蝗亚科(Oedipodinae)和大足蝗亚科(Gomphocerinae)。采用联合序列方法进行分析,结果显示：Cytb 和COI联合序列长度为1 998 bp,其中A和T总含量为72.13%,G和C总含量为27.87%。联合序列共包含了889个保守位点,1 109个变异位点,在这些变异位点中有838个简约信息位点。系统发生树采用邻接法（NJ）、最大简约法（MP）和最大似然法（ML）进行构建。使用蜢总科的变色乌蜢Erianthus versicolor 和 Erianthus sp. 两个种作为外群。结果表明：大足蝗亚科和斑腿蝗亚科的单系性没有得到支持。斑翅蝗亚科内部各种聚成一个大支,在本研究中该亚科的单系性得到支持,与前人的研究结论相同。大足蝗亚科、斑腿蝗亚科、刺胸蝗亚科和黑蝗亚科这4科关系非常近,可以考虑将其合并为一个亚科。同时,我们发现基于Cytb和COI基因联合序列推断蝗科内各亚科间的系统发生关系并不十分可靠。     

Microsatellite loci for the weaver ant Oecophylla smaragdina

We developed 13 microsatellite loci in Oecophylla smaragdina from random amplified polymorphic DNA (RAPD) fragments. These loci showed two to 14 alleles in O. smaragdina with expected heterozygosity of each locus from 0.10 to 0.89, and six were also polymorphic in the related species, O. longinoda. The results suggested that the loci will be useful to analyse the genetic structure of Oecophylla species at both the colony and population levels.     

Oecophylla smaragdina ants provide pest control in Australian cacao

Ecosystem service‐driven methods of agricultural production that make optimal use of an ecosystem's natural services are often effective in smallholder crops, leading increases in habitat heterogeneity at large spatial scales that encourage beneficial species. Pollination services in cacao farms can be enhanced through efforts to conserve pollinator habitats, such as adding cacao fruit husks underneath trees to provide habitat and food resources for midge pollinators. However, it remains unclear how this habitat manipulation affects pest densities or biological control. Here, we evaluated the effects of the predaceous ant Oecophylla smaragdina on three major pests of Australian cacao (Helopeltis spp., Amblypelta spp., and Rhyparida nitida) in an Australian cacao farm, in the presence and absence of cacao fruit husks. We also evaluated the effect of O. smaragdina on their potentially plant‐damaging, mutualistic mealybug (Pseudococcidae) partners in the presence and absence of cacao fruit husks. Oecophylla smaragdina reduced the combined densities of Helopeltis spp. and Amblypelta spp., regardless of cacao fruit husk addition. The ants also reduced the densities of R. nitida in the absence of cacao fruit husks, but R. nitida densities were naturally low in the experimental plots that received the addition of cacao fruit husks, regardless of ant presence. In contrast, ants generally increased the densities of mealybugs. These data suggest that O. smaragdina ants provide pest control services for three major insect pests in Australian cacao farms. Furthermore, this control may be compatible with habitat manipulations (i.e., the addition of cacao fruit husks) to improve pollinator habitat.     

The distribution of weaver ant pheromones on host trees

The visible anal spots deposited by Oecophylla smaragdina ants have been suggested to deter ant prey, affect interspecific competition and facilitate mutualists and parasites in tracking down Oecophylla ants. I measured the density of anal spots on host trees with and without ants and tested for correlations between spot density, ant activity and the likelihood of being detected by an ant. Spots were only found on trees with ants. On ant-trees, spots were distributed throughout the trees but with higher densities in areas with high ant activity and pheromone densities were higher on twigs compared to leaves. Also there was a positive correlation between spot density and the likelihood of being detected by ants. Anal spots may thus function as reliable cues to interacting species and be an important factor in shaping the community around Oecophylla colonies. Received 31 August 2006; revised 27 April 2007; accepted 2 May 2007.     

Phylogeography of Hyalomma (Euhyalomma) lusitanicum (Acarina,Parasitiformes, Ixodidae) in Andalusia based on mitochondrial cytochrome oxidase I gene

The genetic population structure relationships of Hyalomma (Euhyalomma) lusitanicum in Andalusia (the south of the Iberian Peninsula) were examined using mtDNA sequence data from 887 bp of cytochrome oxidase subunit I (COI) gene. The sequence for the COI region was determined for 84 individuals collected in several localities of Andalusia, and 10 for other localities (i.e., five from Toledo, central Iberian Peninsula, four from Sicily (Italy) and one from Canary Island). Seventeen haplotypes were detected, including 27 polymorphic sites. The number of amino acid substitutions per site from mean diversity calculations for the entire population was 0.017. AMOVA analysis revealed a low gene flow that characterises the genetic population structure of this species in South Iberian Peninsula, with a haplotype diversity (h) value of 0.815. No geographically induced differentiation was observed, and separate evolutionary units were not detected. Our results indicate low genetic diversity across the geographical range of H. lusitanicum tick in Andalusia. Our data do not show any genetic discontinuity between the tick populations studied, including specimens from Canary Island and Sicily (Italy).

     

Molecular detection of Cotesia vestalis (Hymenoptera: Braconidae) in the beet webworm Loxostege sticticalis L. (Lepidoptera: Crambidae)

Genomic DNA samples from larvae of the beet webworm Loxostege sticticalis collected in the south‐western Russia were used to amplify mitochondrial cytochrome oxidase unit I (COI) gene. In a small proportion of samples, the sequenced product showed considerable heterogeneity due to admixture of a minor sequence. A preliminary BLAST analysis of a 100‐bp‐long fragment of this minor sequence showed its maximal similarity to the COI gene region of Cotesia, a genus of braconid larval endoparasitoids of Lepidoptera. An additional primer was designed to specifically amplify ca 300 bp of the COI gene region from Braconidae. As many as seven of 25 samples were positive by PCR. Sequencing of the amplified products in all these samples showed nucleotide sequence identity to the COI region of Cotesia vestalis (Cotesia plutellae) and the presence of two molecular haplotypes among individual parasitoid samples.     

Mitochondrial DNA analyses reveal low genetic diversity in Culex quinquefasciatus from residential areas in Malaysia

The present study explored the intraspecific genetic diversity, dispersal patterns and phylogeographic relationships of Culex quinquefasciatus Say (Diptera: Culicidae) in Malaysia using reference data available in GenBank in order to reveal this species' phylogenetic relationships. A statistical parsimony network of 70 taxa aligned as 624 characters of the cytochrome c oxidase subunit I (COI) gene and 685 characters of the cytochrome c oxidase subunit II (COII) gene revealed three haplotypes (A1–A3) and four haplotypes (B1–B4), respectively. The concatenated sequences of both COI and COII genes with a total of 1309 characters revealed seven haplotypes (AB1–AB7). Analysis using tcs indicated that haplotype AB1 was the common ancestor and the most widespread haplotype in Malaysia. The genetic distance based on concatenated sequences of both COI and COII genes ranged from 0.00076 to 0.00229. Sequence alignment of Cx. quinquefasciatus from Malaysia and other countries revealed four haplotypes (AA1–AA4) by the COI gene and nine haplotypes (BB1–BB9) by the COII gene. Phylogenetic analyses demonstrated that Malaysian Cx. quinquefasciatus share the same genetic lineage as East African and Asian Cx. quinquefasciatus. This study has inferred the genetic lineages, dispersal patterns and hypothetical ancestral genotypes of Cx. quinquefasciatus.     

Is the Scotia Sea a centre of Antarctic marine diversification? Some evidence of cryptic speciation in the circum-Antarctic bivalve <Emphasis Type="Italic">Lissarca notorcadensis</Emphasis> (Arcoidea: Philobryidae)

The bivalve Lissarca notorcadensis is one of the most abundant species in Antarctic waters and has colonised the entire Antarctic shelf and Scotia Sea Islands. Its brooding reproduction, low dispersal capabilities and epizoic lifestyle predict limited gene flow between geographically isolated populations. Relationships between specimens from seven regions in the Southern Ocean and outgroups were assessed with nuclear 28S rDNA and mitochondrial cytochrome oxidase subunit I (COI) genes. The 28S dataset indicate that while Lissarca appears to be a monophyletic genus, there is polyphyly between the Limopsidae and Philobryidae. Thirteen CO1 haplotypes were found, mostly unique to the sample regions, and two distinct lineages were distinguished. Specimens from the Weddell and Ross Sea form one lineage while individuals from the banks and islands of the Scotia Sea form the other. Within each lineage, further vicariance was observed forming six regionally isolated groups. Our results provide initial evidence for reproductively isolated populations of L. notorcadensis. The islands of the Scotia Sea appear to act as centres of speciation in the Southern Ocean.     

Cloning of the gene encoding honeybee long-wavelength rhodopsin: A new class of insect visual pigments

Rhodopsins (Rh), G-protein-coupled receptors with seven transmembrane (TM) helices, form the first step in visual transduction in most organisms. Although many long-wavelength (LW) vertebrate opsin sequences are known, less information is available for invertebrate LW sequences. By a combination of RT-PCR and cDNA library screening, we have cloned and sequenced the honeybee LW Rh gene. The deduced protein is composed of 378 amino acids (aa), appears to have seven TM regions, and contains many of the structures and key as thought to be important for Rh function. Phylogenetic analysis of this sequence in relation to other invertebrate Rh reveals it to be a member of a new group of insect LW Rh.     

基于线粒体COI基因序列探讨泥蚶的遗传分化

采用PCR技术对我国沿海地区7个泥蚶群体的线粒体COI基因部分序列进行了测定和遗传分析。在来自7个群体的38个泥蚶样本均得到660 bp的COI基因片段序列,共103个多态位点,组成17种单倍型;数据分析表明：7个群体形成了二大类群：福建以北(包括福建)的5个群体（江苏盐城、浙江奉化、浙江乐清养殖和自然群体、福建福鼎）形成一个类群,类群内的遗传距离为0.0016;福建以南的类群（广东湛江、海南海口）形成一个类群,遗传距离为0.0006;二个类群之间的遗传距离为0.1529,表现为高度的分化。因此我国沿海泥蚶已分化形成福建以南和以北二大类群,二大类群之间的遗传分化已达到亚种水平。     

Genetic diversity and phylogeny of the Kanzawa spider mite, Tetranychus kanzawai, in Japan

Two types are known in the Kanzawa spider mite, Tetranychus kanzawai (K and T; see Gotoh et al., 1999), which differ in host range and have a unidirectional incompatibility. Prior to DNA analyzes, crossing between females of a known K type and males of each of 17 strains collected in Japan showed that six of the strains were of the K type, five were the T type and the rest consisted of a mixture of the two types. In order to elucidate the genetic diversity and phylogenetic relationship of T. kanzawai in Japan, we analyzed the DNA sequences of two regions – the internal transcribed spacer 1 (ITS1) of the nuclear ribosomal DNA (rDNA) and a fragment of the cytochrome oxidase subunit I gene (COI) of mitochondrial DNA – using 11 strains (six K-type strains and five T-type strains). Base substitutions were detected on 25 sites of COI (375bp) and 19 sites of ITS1 (486bp), resulting in eight and 17 haplotypes, respectively. The phylogenetic trees constructed using the DNA sequences failed to clearly distinguish between the two types. The results suggested that the T type was derived from the K type.     

A divergent lineage among Octopus minor (Sasaki, 1920) populations in the Northwest Pacific supported by DNA barcoding

Octopus minor (Sasaki, 1920) is an important economic fishery resource in China. In order to explore the stock information and the phylogeographic status of O. minor, mitochondrial DNA cytochrome c oxidase subunit I (COI, 565?bp) and 16S rRNA (493?bp) genes were amplified from 11 different sampling locations. Genetic diversity evaluated by haplotypic and nucleotidic diversity implied high diversity in Lianjiang, and relatively low diversity in Rongcheng, which suggests that effective measures to protect the O. minor resource in this area are urgently required. Private haplotypes and remarkable higher pairwise Φ_ST in Yilan are responsible for the deep genetic divergence between Yilan and the 10 other populations. Haplotypes networks and two clusters’ topological structure also support the distinct subgroups (lineages A and lineages B), which apparently possess smaller genetic variation than mean interspecies distance. Taiwan island and its strait may act as a natural barrier that restricts the gene flow from the mainland. Deep genetic divergence between mainland and Taiwanese east coasts suggests different genetic stock, indicating that different management strategies are required.     

Phylogeography of <Emphasis Type="Italic">Ceriops tagal</Emphasis> (Rhizophoraceae) in Southeast Asia: the land barrier of the Malay Peninsula has caused population differentiation between the Indian Ocean and South China Sea

The genetic structure of mangrove species is greatly affected by their geographic history. Nine natural populations of Ceriops tagal were collected from Borneo, the Malay Peninsula, and India for this phylogeographic study. Completely different haplotype compositions on the east versus west coasts of the Malay Peninsula were revealed using the atpB-rbcL and trnL-trnF spacers of chloroplast DNA. The average haplotype diversity (Hd) of the total population was 0.549, nucleotide diversity (θ) was 0.030, and nucleotide difference (π) was 0.0074. The cladogram constructed by the index of population differentiation (G _ST) clearly separated the South China Sea populations from the Indian Ocean populations. In the analysis of the minimum spanning network, the Indian Ocean haplotypes were all derived from South China Sea haplotypes, suggesting a dispersal route of C. tagal from Southeast Asia to South Asia. The Sunda Land river system and surface currents might be accountable for the gene flow directions in the South China Sea and Bay of Bengal, respectively. The historical geography not only affected the present genotype distribution but also the evolution of C. tagal. These processes result in the genetic differentiation and the differentiated populations that should be considered as Management Units (MUs) for conservation measurements instead of random forestation, which might lead to gene mixing and reduction of genetic variability of mangrove species. According to this phylogeographic study, populations in Borneo, and east and west Malay Peninsula that have unique genotypes should be considered as distinct MUs, and any activities resulting in gene mixing with each other ought to be prevented.     

四纹豆象不同地理种群的遗传分化

【目的】通过对四纹豆象Callosobruchus maculatus Fabricius不同地理种群mtDNA-Cytb和COⅠ基因部分序列进行比较, 分析其不同地理种群间的遗传分化情况, 为揭示其与生物入侵的关系及入侵过程中种群系统发育地理格局与演变机制提供依据。【方法】用PCR产物直接测序法对分别来自中国海南、喀麦隆、韩国和泰国的四纹豆象4个地理种群的mtDNA-Cytb和COⅠ序列进行测序, 运用软件MEGA3.1对四纹豆象不同地理种群mtDNA-Cytb和COⅠ序列进行序列分析, 以绿豆象C. chinensis为外群构建了不同单倍型的分子系统树。【结果】34条420 bp Cytb序列中共检测到14个多态位点和5种单倍型, 33条822 bp COⅠ序列中检测到28个多态位点和9种单倍型, 其中4种单倍型为独享单倍型, 其余为全部或部分种群的共享单倍型。AMOVA分析结果显示, 四纹豆象4个地理种群间的遗传结构差异并不明显, 遗传差异主要发生在地理种群内。对4个地理种群进行了Fst值和基因流动统计, 结果表明4个地理种群间既存在着一定数量的基因交流, 也存在一定程度的遗传分化。【结论】根据单倍型分布格局初步推测, 中国不可能是四纹豆象的原产地, 而喀麦隆有可能是原产地之一, 并且喀麦隆种群与泰国种群之间的基因交流比较充分, 而中国种群与其他种群之间的遗传分化相对较大。     

Evaluation of DNA barcoding and identification of new haplomorphs in Canadian deerflies and horseflies

This paper reports the first tests of the suitability of the standardized mitochondrial cytochrome c oxidase subunit I (COI) barcoding system for the identification of Canadian deerflies and horseflies. Two additional mitochondrial molecular markers were used to determine whether unambiguous species recognition in tabanids can be achieved. Our 332 Canadian tabanid samples yielded 650 sequences from five genera and 42 species. Standard COI barcodes demonstrated a strong A + T bias (mean 68.1%), especially at third codon positions (mean 93.0%). Our preliminary test of this system showed that the standard COI barcode worked well for Canadian Tabanidae: the target DNA can be easily recovered from small amounts of insect tissue and aligned for all tabanid taxa. Each tabanid species possessed distinctive sets of COI haplotypes which discriminated well among species. Average conspecific Kimura two‐parameter (K2P) divergence (0.49%) was 12 times lower than the average divergence within species. Both the neighbour‐joining and the Bayesian methods produced trees with identical monophyletic species groups. Two species, Chrysops dawsoni Philip and Chrysops montanus Osten Sacken (Diptera: Tabanidae), showed relatively deep intraspecific sequence divergences (～10 times the average) for all three mitochondrial gene regions analysed. We suggest provisional differentiation of Ch. montanus into two haplotypes, namely, Ch. montanus haplomorph 1 and Ch. montanus haplomorph 2, both defined by their molecular sequences and by newly discovered differences in structural features near their ocelli.