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Mayflies are important as macroinvertebrates of aquatic ecosystems and are reliable bioindicators of water quality. Most mayfly nymphs feed by scraping algae from underwater rocks or by extracting food particles in the littoral and benthic zones of the water bodies. The mayfly Povilla (Languidipes) taprobanes originally described from Sri Lanka was observed in plastic lined ponds in coastal Karnataka. Not only, this is the first report of the species from Karnataka, but the unique case making behaviour of this species is also described for the first time. Additionally, the species was found damaging plastic tarpaulins of 750 gsm thickness used as lining for water storage in the tank by chewing. This chewing behaviour was responsible for damage of plastic sheets leading to water leakage. The possible loss caused and a need of alternate strategies to store water is discussed.

Fluorine, which occurs naturally as fluoride in the earth’s crust in small amounts, is essential to humans and animals and is known to stimulate plant growth when present in small concentrations. However, higher concentrations of fluoride in drinking water cause dental and skeletal fluorosis in animals and humans and when present in high concentrations in groundwater used for irrigation, it accumulates in the plants and the soil and causes undesirable effects. A study was carried out during kharif, 2015 and rabi season of 2015-16 in Talakondapalle Mandal of Rangareddy District, Telangana state, India, to measure and map the distribution of fluoride in groundwater in borewells used for irrigation, to observe seasonal variation in fluoride content and to examine the relationship of fluoride with other water quality parameters such as pH, EC, Cl-1, CO3-, HCO3-, SO4-2, Ca+2, Mg+2, Na+, K+, RSC and SAR. Fluoride in groundwater ranged between 0.72 to 4.50 ppm with a mean of 2.84 ppm and standard deviation of 1.30 ppm in kharif season and from 1.32 to 4.92 ppm with a mean of 3.29 ppm and standard deviation of 0.24 ppm in rabi season. Except for two borewells in kharif, fluoride concentration was higher than the permissible limit of 1 ppm. Groundwater fluoride map of the study area was generated using kriging technique. Fluoride concentration was higher in all the borewells in rabi over kharif with mean fluoride concentration being 15.8% higher in rabi season. Fluoride concentration was significantly positively correlated with pH, HCO3-, Na+, SAR and RSC of ground water and significantly negatively correlated with Ca+2.

Euhamitermes Holmgren is a soldier rare, soil feeding termite of the Oriental region. Two species of this genus viz., Euhamitermes lighti (Snyder) and Euhamitermes chhotanii Maiti are hereby first reported from southern Indian states of Karnataka and Kerala, respectively. Record of E. chhotanii in Kerala makes an addition of the genus and thus to the termite fauna of Kerala. These two species are redescribed and illustrated based on soldier and workers.

International audience; We measured noble gas concentrations and isotopic ratios (He, Ne, and Ar isotopes) in six recent ordinary chondrite falls: Mangui (L6), Vinales (L6), Ozerki (L6), Tamdakht (H5), Kheneg Ljouad (LL5/6), and Katol (L6). Among them, the three L6 chondrites Mangui, Vinales, and Ozerki fell in only a few months interval; their apparent similar petrographic and mineralogic characteristics might indicate source crater pairing. To test this hypothesis, we have investigated those meteorites for their cosmic ray exposure (CRE) histories, using the cosmogenic noble gases He-3, Ne-21, and Ar-38. We systematically (re)calculated the CRE ages as well as the gas retention ages of these meteorites. The CRE age of the Mangui is, based on noble gases

Background: In recent times, termites have gained importance in agriculture as a pest in wheat crop. Famers are using chemical pesticides for the management of termites, which eventually leads to degradation of soil, insecticide residue, pest resurgence, air pollution, water pollution and also affects human health. In this regard, botanicals as an effective alternate to insecticides in the management of termites is crucial. The root and leaf extracts of Crotalaria burhia Buch-Ham and Anacardium occidentale L. against termites was evaluated. Methods: Field experiments were conducted to assess the efficacy of botanicals viz., Crotalaria burhia Buch-Ham and Anacardium occidentale L. along with Indigenous technologies, biofungicide and standard chemicals against Odontotermes obesus Rambur in wheat. An experiment was laid at the Research Farm, Institute of Pesticide Formulation Technology, Gurgaon, Haryana during two seasons, i.e., November 2014-March 2015 and during December 2015-April 2016. Result: The test botanicals incorporated along with indigenous technologies and widely recommended termiticides assessed for their efficacy against O. obesus in wheat at two locations proved to be effective in the order of imidacloprid 17.8 SL at 350 ml ha-1 greater than chlorpyrifos 20 EC at 2 l ha-1 greater than B. bassiana 2x108 at 500 ml ha-1 greater than C. burhia root extract (10%) at 50 l ha-1 greater than A. occidentale leaf dust (5%) at 25 kg ha-1 greater than irrigating plots greater than neem oil (2%) greater than dusting salt at 25 kg ha-1.

A short investigation was devised by Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore in 2022 to document the arthropod composition in sugarcane (Saccharum officinarum L.) ecosystem. Arthropod fauna was collected from sugarcane ecosystem in farmers’ field at Puthur of Coimbatore district, Tamil Nadu at weekly intervals. Totally, 2,310 individuals of the subclass Pterygota were collected and among them most of specimens belonged to Exopterygota. The exopterygota (1,029) were represented by 5 orders, viz. Hemiptera, Odonata, Orthoptera, Isoptera and Dermaptera. Majority of the individuals belonged to the family Aphididae (330) under the order Hemiptera. Under order Orthoptera, Gryllidae (46) was the dominant family closely followed by Acrididae (45). Among these, the dominant species was Gryllus spp. The order Odonata was represented by a single family Libellulidae (38) and the species was identified as Orthetrum sabina Drury, 1773. Under Endopterygota, 4 orders were identified and among these, Hymenoptera was the most common order with 740 numbers, followed by Diptera (237), Coleoptera (215) and Lepidoptera (89). Under the order Coleoptera, 3 families were recorded, with most of them falling under the family Coccinellidae (172) followed by Cicindelidae. Hymenopteran order comprised majorly of ants, belonging to the family Formicidae, of which 3 species were identified. Lepidoptera consisted of single species Ariadne merione Cramer, 1779 belonging to family Nymphalidae. Majority of Arachinda was represented by order Araneae. Under the order Araneae most of them pertained to families Araneidae, Lycosidae and Thomisidae. Neoscona sp., Hippasa sp., Pardosa sp. and Pardosa birmania Simon were found to be common in sugarcane ecosystem.

Biodiversity being a multidimensional property is always considered as tough to measure or quantify mostly because of the assortment of indices recommended for this purpose. However, there is no agreement about which indices are more appropriate and informative. Arthropods are one of the groups that have evaded the knowledge of human beings of their role in ecosystem function. We used data collected from floricultural ecosystems of rose, jasmine and cock’s comb fields during 2016 in Coimbatore, Tamil Nadu and calculated common arthropod diversity indices of species richness and species dominance in ordinal, familial and species level. The aim was to find out whether surrogacy is possible as far as arthropod diversity analyses are concerned and to determine whether some were better suited than others. In the present study, it was found that in most of the cases, irrespective of the index used, estimating species richness based on family level presented a closer picture to that of species level analysis, but could not totally replicate the sensitivity reflected by species level classification. Of the three dominance indices, only the Simpson's index discriminated the variation at all the three levels, viz. ordinal, familial and species with the discrimination being more pronounced at the species level. Hence, it could be inferred that the Simpson index could successfully be used in the floricultural ecosystems for estimating arthropod diversity based on dominance measures.

A checklist of termites (Blattodea: Isoptera) of southern India with their distribution is presented in this paper. In total, 132 species from five families are listed, of which Termitidae Latreille, 1802 is the dominant family comprising 101 species from 27 genera and four subfamilies. The recent additions of species to the regional termite diversity are Krishnacapritermes dineshan Amina & Rajmohana, 2020, K. manikandan Amina & Rajmohana, 2020, and Pseudocapritermes kunjepu Mathew, 2020. Out of 132 species recorded from southern India, 60 species and five genera are endemic to the region, and the subfamily Termitinae Latreille, 1802 accounts for maximum endemism.

Threading has become quite popular in recent years as an alternative to tapping or other forms of threading because of diversity and complexity of parts and flexibility of the process in industries such as biomedical applications, aerospace and die-mold manufacturing. However threading is one of the complex and critical operations due to its tool geometry. To analyze the threading parameters by means of design of experiment concept wit response surface methodology. The full factorial design is used for experimental design. The three levels of spindle speed and depth of cut are used as an input parameter. Similarly responses are material removal rate, surface roughness and forces such as feed force, trust force and cutting force during threading operation. The main objective of this study is to evaluate the difference between the Square thread and pilot v grooved square thread to maximize the surface finish of threading. And also to determine the responses, such as Material Removal Rate (MRR), Surface Roughness, and Forces for square thread and the pilot grooved square thread. Based on the analysis pilot v grooved square thread is better than square thread. As a result in Square Thread and pilot v grooved square thread responses such as Feed Force, Thrust Force, Cutting Force, and MRR and is high. Surface Roughness is high only in Square Thread compared with pilot v grooved square Thread.

Performance of heat exchanger is evaluated by the value of heat transfer coefficients, Reynolds number, Nusselt number, temperature distribution along the length, residence time and pressure drop. Improving these parameters for better performance is the main focus in designing the heat exchanger. In that view, helical coil gives more turbulence to the fluid flowing through it that leads to improved tube side heat transfer coefficient. For increasing the turbulence in cold flow, turbulators can be used in the circumferential area between helical coil and shell. In this work, heat transfer rate of shell and helical coil heat exchanger is improved by using circumferential turbulators. For the same mass flow rate of cold fluid different hot fluid mass flow rates (0.03 kg/s, 0.06 kg/s, 0.09 kg/s and 0.12 kg/s) were fixed for taking readings and the improvement is obtained by calculation of performance parameters. The temperature distribution along the length of the heat exchanger is plotted for different flow rates. Results show that, increasing the mass flow rate of cold fluid above the mass flow rate of hot fluid decreases the performance.

Several termite species are significant economic pests, causing damage to wood in both man-made structures and also in forest ecosystem. The species belongs to genus Coptotermes (Rhinotermitidae: Isoptera: Blattodea) are widespread and few of them are among the world’s most dangerous wood pests. Two species of Coptotermes were collected, identified and described from yemene, mora and tali logs imported from Columbia, Suriname and Equitorial Guinea. These two intercepted species are non-native to India which are Coptotermes testaceus (Linnaeus) and Coptotermes sjostedti Holmgren. Identification was initially made with morphological characters and then with molecular DNA barcoding for a 348 bp fragment of 16S rRNA gene. Maximum likelihood Phylogenetic analysis results showed that data recovered as monophyletic which confirms the species identity. Coptotermes testaceus and C. sjostedti are in single clade. Coptotermes testaceus is neotropical in origin and C. sjostedti is native to Africa. Both the species are known to be serious pests in human habitats and forest ecosystem in the regions of their distributions. This first interception suggests possible chances of entry and establishment in India and provides an important alert for authorities concerned to take the necessary steps in monitoring and preventing its possible introduction. The importance of quarantine and potential infliction of damage they may cause if unnoticed and future measures to be taken are discussed.