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Analysis of evolutionary divergence of Neurothemis tullia (Odonata:Libellulidae) using cytochrome oxidase subunit I gene
... It also has high nucleotide substitution rate and hence helping for discriminating cryptic species (Surajit et al., 2014). There were many reports on the prompt application of mitochondrial CO I gene based DNA barcoding for the accurate identification of various odonate species from present authors ( Jisha and Sebastian, 2016a;2016b;2015a;2015b;2015c;2015d;2015e). ...
... It also has high nucleotide substitution rate and hence helping for discriminating cryptic species (Surajit et al., 2014). There were many reports on the prompt application of mitochondrial CO I gene based DNA barcoding for the accurate identification of various odonate species from present authors ( Jisha and Sebastian, 2016a;2016b;2015a;2015b;2015c;2015d;2015e). ...
The Gomphidae represents one of the fast flying dragonfly families of the insect order Odonata, widely distributed in Palaertic, Ethopian and Oriental regions. Members can be easily diagnosed by having a club like swelling at the base of abdomen (Clubtails) and also black stripes could be seen on their yellow or green coloured thorax. They are habitat specialist and ecologically important as indicators of clean aquatic ecosystem and predators certain dragonflies also. Onychogomphus malabarensis is an endemic Gomphidae member reported only from the forest ecosystem of Palakkad District of Kerala. Here we amplified the cytochrome oxidase I gene and its sequence was deposited in the Gen Bank (KX503058) for future references. The nucleotide BLAST analysis showed that this species is having 100% sequence similarity to Ophiogomphus anomalus reported from America (KX890962). The entire study states that the molecular barcode is a new report to NCBI and their phylogeny inferred their specific taxonomic position among other Gomphidae members.
The taxonomy of the Odonata group is still poorly understood; therefore, molecular identification has been developed to address the shortcomings of traditional taxonomy, such as misidentification and inconsistencies in reference databases. The mtCOXI gene has been used in animal barcoding studies because of its wide range of phylogenetic signals. Odonata, a diverse group of aquatic insects, has been studied at the molecular level to understand the evolutionary relationships between their species and global species. In the current study in Basrah Province, Iraq, we extracted mitochondrial DNA from adult and nymph Dragonflies and designed species-specific primers to distinguish some of the endemic species at the molecular level. This study identified five species, Crocothemis erythraea, Diplacodes trivialis, Orthetrum sabina, Trithemis annulata and Hemianax ephippiger. The DNA sequences were deposited in the NCBI database for the first time. The nucleotide sequences of the mtCOXI genes were analyzed via BLAST. The similarity results ranged from 91.8% to 100%, indicating related species on the basis of the branches of the phylogenetic tree. The molecular identity of the selected species was confirmed, and DNA barcodes for Anisoptera species from Basrah Province were successfully developed and documented in GenBank and IBIN.
The present study depicts the first ever DNA barcoding study of Odonates from the State of Kerala, India. The northern part of the state, which corresponds to the western side of the western ghats, was the focus of the study. The study has been conducted as this region is blessed with ample annual rainfall brought on by the southwest monsoon, making it the ideal habitat for many Odonata species documented here. In total, of the 70 specimens collected, 37 cytochrome oxidase subunit I (COI) sequences belonging to 31 species were deposited in the public repositories (NCBI and BOLD) for future reference. This report produced five new DNA barcodes consisting of two endemic species (Onychogomphus malabarensis and Agriocnemis keralensis), two Coenagrionidae members (Ceriagrion coromendelianum and Aciagrion occidentale), and one Libellulidae member (Lathrecista sp.) from Kerala, along with five novel reports from India. We also checked the inter-family relationships of the six dominant families and analyzed the monophyletic ancestry of the order Odonata. The study predicted monophyletic ancestry in both Zygopterans (damselflies) and Anisopterans (dragonflies) over the taxonomically nearer outgroup (Ephemeroptera) taken for the analysis. This also confirmed the inter-family relationship between these members of the suborders Anisoptera (Libellulidae, Gomphidae, and Aeshnidae) and Zygoptera (Coenagrionidae, Platycnemididae, and Calopterygidae). Thus, the cytochrome oxidase I gene nucleotide substitution analysis attributes neutral evolution to all species, irrespective of their geographical areas.
For the past few years, DNA barcoding has become an efficient method for the identification of species. In this study we test the efficiency of DNA barcoding for true bug, Zicrona caerulea (Hemiptera: Heteroptera), an ecologically and economically important as well as morphologically diverse insect taxon. These bugs are useful predators of leaf beetles of the genus Altica, larvae of various beetles and caterpillars of moths, and it also feeds on plants. The study emphasizes the use of DNA barcodes for the identification of Zicrona caerulea and to represent an important step in building-up a comprehensive barcode library for the true bugs. As part of our study we analyzed DNA barcodes of Zicrona caerulea isolated from Kerala and its phylogenetic status with other related taxonomic groups. The PCR amplified cytochrome oxidase subunit I gene (COI) partial sequence of Zicrona caerulea has 1.11% difference to that of Zicrona caerulea (GenBank Accession: GQ292256) of Seoul, Korea and 1.68% difference to Zicrona caerulea (KM023126) Bremen, Germany.
For taxonomists Neurothemis is a confusing genus under Order Odonata, because of the morphological variants existing within the species.. Here we have analysed the phylogenetic relationships of three different species of Neurothemis by the partial sequencing of mitochondrial cytochrome oxidase subunit I (COI) gene. Phylogenetic tree constructed by Neighbour joining method proved that Neurothemis tullia and Neurothemis intermedia are taxonomically more closer and they together formed a single clade in the tree. Neurothemis fulvia is sister to this clade but it represents the most diverged species in terms of branch lengh and nucleotide substitution. Comparison with the retrieved sequences confirmed that it strictly belong to Libellulidae family. The tree also depicted that Neurothemis genus is more close to Orthetrum sabina than Diplacodes trivalis. Hence the study concluded that DNA barcoding is an invaluable tool for confirming the species identification and to assess the proper phylogenetic relationships. ABSTRACT
DNA barcoding has become the method of choice for a rapid, reliable, and cost-effective identification of pest species. Since DNA barcoding have proven to be highly efficient in identifying both immatures and adults, it is used to differentiate invasive and native pests. It has been used in managing species complexes in agricultural, IPM systems and also in the cases unpredictable species. Recently, DNA barcoding of partial mitochondrial COI gene is very popular in DNA based identification of various agricultural pest species. The present study investigates the molecular evolution of the Asota species using COI gene and its usefulness for reconstructing phylogenetic relationships within and among different Asota species.
The family Delphacidae is the largest and most economically important one amongst the hoppers, Fulgoroidea. It has representatives in tropical and subtropical regions that occur in a variety of environments, and its known fossil records dates back to Jurassic period. Sogatella furcifera, the white backed plant hopper is a serious pest of rice in many Asian countries. We have performed the phylogenetic reconstruction of the S. furcifera using the mitochondrial cytochrome oxidase subunit I (COI) gene. Phylogenetic reconstructions of the COI regions were done using Neighbor joining method. This study gives a clear picture of the mitochondrial genome of the insect and gives the phylogenetics of S. furcifera which help us to develop a sustainable and accurate strategy for management of the pest.
Lepidoptera is one of the largest orders of insects that include moths and butterflies. Most of the Lepidopterans are morphologically similar, therefore the identification of these insects is tedious using morphotaxonomy and that is detrimental in designing a better strategy to control and conserve them. These are extremely important group of 'model' organisms and are used to investigate many areas of biological research, including such diverse fields as navigation, pest control, embryology, mimicry, evolution, genetics, population dynamics and biodiversity conservation. The knowledge of Lepidopteran genomics will create new methods of insect pest management and will contribute to sustainable agriculture, protection of the environment and the maintenance of biodiversity. In this study we amplified cytochrome oxidase I gene of Junonia atlites for species identification and constructed phylogenetic tree for recognizing evolutionary relationship.
We announce the release of an advanced version of the Molecular Evolutionary Genetics Analysis (MEGA) software, which currently contains facilities for building sequence alignments, inferring phylogenetic histories, and conducting molecular evolutionary analysis. In version 6.0, MEGA now enables the inference of timetrees, as it implements our RelTime method for estimating divergence times for all branching points in a phylogeny. A new Timetree Wizard in MEGA6 facilitates this timetree inference by providing a graphical user interface (GUI) to specify the phylogeny and calibration constraints step-by-step. This version also contains enhanced algorithms to search for the optimal trees under evolutionary criteria and implements a more advanced memory management that can double the size of sequence data sets to which MEGA can be applied. Both GUI and command-line versions of MEGA6 can be downloaded from www.megasoftware.net free of charge.
Probability models of branching processes and computer simulations of these models are used to examine stochastic survivorship of female lineages under a variety of demographic scenarios. A parameter II, defined as the probability of survival of two or more independent lineages over G generations, is monitored as a function of founding size of a population, population size at carrying capacity, and the frequency distributions of surviving progeny.
Stochastic lineage extinction can be very rapid under certain biologically plausible demographic conditions. For stable-sized populations initiated by n females and/or regulated about carrying capacity k=n, it is highly probable that within about 4n generations all descendants will trace their ancestries to a single founder female. For a given mean family size, increased variance decreases lineage survivorship. In expanding populations, however, lineage extinction is dramatically slowed, and the final k value is a far more important determinant of II than is the size of the population at founding. The results are discussed in the context of recent empirical observations of low mitochondrial DNA (mtDNA) sequence heterogeneity in humans and expected distributions of asexually transmitted traits among sexually reproducing species.
The life history was studied from June 1993 through April 1995 in a rainfed rice field of Bandar Baru District in Kedah, Peninsular Malaysia. Larval growth was more uniform during early instars. Increasing variations of growth were obvious during the later instars, especially in the final instar. Plots of head width against wing bud length and body length enabled instars to be determined. Larval development was asynchronous and a maximum of 8 larval instars was found on one sampling occasion. 4 emergences were observed in 1994, in March, May, July and October. In general emergence was relatively synchronized. The E50 values were achieved within the first 38%, 9% and 16% of the total duration of emergences 2, 3, and 4 respectively. A relatively short life cycle, continual breeding and oviposition, synchronous emergence and immediate reproduction after a dry period ensure survival of N. tullia in the unpredictable rainfed rice ecosystem.