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Dry fish is considered as a delicacy in the menu of many people of Bangladesh. The most economically important marine and freshwater dried fishes are ribbon fish, bombay duck, olive barb, pomfret, shrimp, etc. In this study, fresh ribbon fish sample was collected from Cox's Bazar and morphologically identified as ribbon fish. The collected fish was confirmed through a molecular technique using mitochondrial COI gene (cytochrome c oxidase subunit I) to avoid morphological ambiguity, which is first reported data from Bangladesh. Partial sequence of this COI gene was amplified using a genus specific universal primer set. The target nucleotide sequence of COI gene was determined successfully with 616 bp length and the ribbon fish was identified as Eupleurogrammus sp. Within the amplified region GC and AT content were 45.5% and 54.5%, respectively. 16.88% interspecific polymorphism was observed when compared with other species under genus Eupleurogrammus collected from Gen Bank database. This sequence will be used as molecular bar code for authentic identification of Eupleurogrammus sp. at genus level. Bangladesh J. Zool. 50 (2): 231-238, 2022

In this study, effect of increasing temperature on life cycle, mortality, and behavior of the mosquito species, Aedes aegypti was evaluated. Heat shock was applied at 32°C, 37°C and 42°C for 20 minutes, 1 hour and 2 hours for each temperature to egg, 2nd instar, 3rd instar and pupal stage separately and changes in life cycle pattern was recorded on a routine basis. The control temperature was 27°C at which the mosquito was reared. When heat-shock was applied to eggs, the developmental period for each stage was found to be inversely proportional to temperature rise. The shortest embryonic developmental period was recorded at 32°C, and the shortest larval and pupal stages were recorded at 37°C (2h). The shortest full development period was also found to be at 37°C (2h). No hatching was recorded at 42°C. While heat shock was applied to 2nd instar larvae, 3rd instar larvae and pupae, similar decreased pattern was observed. In this study, 100% viability was observed upon heat shock to eggs, larvae (2nd and 3rd instar) and pupae at 27°C and 32°C. In case of 37°C, egg, 2nd instar and pupal viability decreased. No egg hatched at 42°C, while few 2nd instars survived. Lowest viability rate for 3rd instar larvae and pupae were counted at 42°C. Change in the rate of movement also decreased gradually with increasing temperatures in pupae. The change was irregular in case of 2nd and 3rd instar larvae. The highest movement was recorded for 2nd and 3rd instar larvae at 32°C and 27°C, respectively and lowest was recorded at 42°C. Bangladesh J. Zool. 49 (3): 369-379, 2021

Climate change is responsible to a certain extent for the occurrence and spread of arboviral pathogens worldwide. Temperature is one of the crucial abiotic factors influencing the physiological processes of mosquitoes. Several genes of heat shock protein (AaeHsp26, AaeHsp83, and AaeHsc70) families are known to be expressed in mosquitoes, which aid in overcoming stress induced by elevated temperature. In this study, the relative expression of heat shock protein genes has been examined using Quantitative Real-time PCR (qPCR). The temperatures used for heat shock treatment were 27(control), 37, and 42°C for 1 hour heat shock period and applied to 3rd instar larvae. Significant up-regulation has been seen at 37, and 42°C. The highest expression level, about 82.43 fold, was reported for the AaeHsc70 gene at 42°C followed by 78.36 fold for AaeHsp26 at 37°C and 4.79 fold for AaeHsp83 at 42°C. The current study has shown that HSPs are important markers of stress and may function as critical proteins to protect and enhance the survival of Ae. aegypti larvae and pupae. Biological implications of these findings could impact the vector competencies Dhaka Univ. J. Biol. Sci. 30(2): 233-241, 2021 (July)