Background: Insect wings are an excessively diverse structures, which have fascinated scientist for centuries. Coleoptera is the largest order in the insect group and the most successful animal on earth (Nature Communications 9(205):1-11, 2018). In order to adapt to the change in the environments, they developed strategies to cope up with different factors. The most distinctive feature of beetles is that the forewings are sclerotized into elytra; from this, they get their formal name (koleos = sheath, pteron = wing). The elytra play an important role in protecting the delicate hindwings and the dorsal surface of the abdomen. Besides its influence on protective the hindwing during flight, the forewings are open enough to allow the hindwings to unfold and function. Result: The structural and mechanical properties in living organisms may improve the understanding of natural solutions and advance the design of novel artificial materials. In this paper, the morphological and histological structure of the wings of two species of beetles, Tribolium castaneum and Tribolium confusum, has been investigated using scanning electron microscopy (SEM). The organic chemical function groups of the wings were detected using Fourier-transformed infrared spectroscopy (FTIR). Both Tribolium species have considerable variations regarding the total thickness, and width of the hemolymph space within the elytra. The elytra of both species bear conspicuous field of trichoid sensilla from dorsal side and numerous gland openings with a pit. The michrotrichia found on the ventral side may have an important role in wing folding. The presence of C-H stretching bands with the prevalence of methylene bands may indicate the presence of long-chain aliphatic acids in surface waxes in T. castaneum. The height of the spikes of the hindwings was remarkable by hydrogen-bonded O-H and N-H amide stretching vibration and was correlated to the thickness of the wing. Conclusion: Insect wings are a core example of histological and morphological novelty. This study illustrates the morphological and histological structure of both the forewing and hindwing of Tribolium castaneum and Tribolium confusum which were the most destructive pest stored products.

In the present study, the effect of flufenoxuron on the sensory organ in the antenna of Spodoptera littoralis was showed after feeding of the 3 rd larval instars for 24 hrs. on treated castor been leaves with Lc 50 . Each adult antenna, male and female of untreated and treated group is divided into about 77-82 segment like annuli; and each segment is divided into a sensory region containing the olfactory sensilla and a largely non-sensory region containing scales and a very small number of sensory structures.Six types of sensilla were found on the antenna of adult S. littoralis: by scanning electron microscopy. These sensilla were trichoidae, chaetica, coeloconica, taste rod, sensilla auricillica and squamiforms.Two types of sexually dimorphic trichoidae were found; Type I is in the peripheral of the sensory field of the flagellar segments and present only on male antennae. This suggests that the sensillum may contain the receptor sites for the female sex pheromone. Type II is located within the ventromedial sensillar field of male and female where they are arranged without apparent pattern.Six mechanoreceptive sensilla chaetica on each segment of male and female were particularly abundant on the apical antennal segment.Each flagellar segment bears several sensilla coeloconica on the ventral surface of the antennae. Each sensillum consists of a depression surrounded by 15 to 17 teeth and one peg.There was a single sensillum taste rod on each segment. There is one of these sensilla at each segment in both male and female. On the terminal segment there were two sensilla joined.Sensilla auricillica were found on both male and female. These sensilla usually had a typical rabbit ear shape.The squamiform sensilla are found on both male and female on the dorsal part of the antenna among the scales.The study revealed that LC 50 of flufenoxuron caused the formation of abnormal antennae and effect the length and distribution of the sensilla.

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The comparative toxicity of ten selected native essential and edible oils was assessed against S. granarius. The oils used are black seed oil (Nigella sativa), Sesame oil (Sesamum indicum), olive oil (Olea europaea), Peppermint oil (Mentha piperita), Basil Oil (Ocimum basilicum), orange oil (Citrus sinensis), Rosemary oil (Rosmarinus officinalis), Clove oil (Dianthus caryophyllus), Garlic oil (Allium sativum), and Cinnamon oil (Cinnamomum zeylanicum). Different concentrations of oils were mixed with wheat grains and provided for adults in test tubes. Mortalities were recorded for 3 days post-treatment. The overall results showed that Garlic oil was the most toxic and Rosemary was the least toxic among both edible and essential oils. A direct correlation was found between oil dose and percent mortality of adults under all exposure periods. The recorded values of LC 50 and the toxicity index showed that Sesame oil was the most toxic edible oil followed by Black seed and Olive oils. The essential oils used can be arranged in descending order according to their toxicities to S. granarius adults as follows: Garlic > clove > Cinnamon > Basil > Orange > Peppermint> Rosemary. All the fixed and essential oils used, demonstrated satisfactory activity and proved to be promising as control agents of S. granaries and consequently other similar stored product insects. Some oils were highly toxic at low concentration and short exposure time; whereas some oils might be required in higher concentrations and longer exposure time to achieve satisfactory control of the insects.

Background: The confused flour beetle Tribolium confusum Jacquelin du Val (Coleopteran: Tenebrionidae) is the most destructive pest of stored products worldwide. It is the most common pest of wheat flour. Results: This study describes and illustrates the larvae, pupae, and adults of T. confusum using scanning electron microscopy. The first larval instars are 5.0-5.1 mm long and 0.5-0.6 mm wide whereas the last larval instars are 5. 75-6.9 mm long and 0.75-0.95 mm wide. Adults of T. confusum are reddish brown elongate beetles (4.0-4.5 mm in body length and 1.0-1.2 mm in width). Electron micrographs revealed the structure of the mouth parts during the larval, pupal, and adult stages as well as the structure of thoracic and abdominal appendages. Results indicated that the setiferous sex patches which were reported in males can often be used for sexing specimens. A specific feature of the first instar larvae of T. confusum is the extreme shortened antenna with a reduced number of antennomeres and the presence of well-developed and moderately long legs. Conclusion: SEM examination may help us not only discover and understand new morphological details as the pits with spine on the elytra and the spikes on the membrane wings which will facilitate the identification of this species but also clarify the functions of various body parts.