Ceylon Journal of Science (Biological Sciences)
Permanent URI for this collectionhttps://dl.nsf.gov.lk/handle/1/7565
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Item Diel oviposition activity of Armigeres subalbatus (Diptera, Culicidae)(1995) Weerasekara, S.K.; Amarasinghe, F.P.The diel oviposition activity of Armigeres subalbatus (Coquillett) was investigated under natural conditions in a shaded home-garden habitat in Kandy. A total of 28,771 eggs of this species were collected in an ovitrap during 10 diel cycles carried out in December 1987 - January 1988. Oviposition activity was biphasic, with a major peak at sunset and a secondery peak of sunrice. The diel oviposition profile was similer to the biting profile of the species and it appears that rapid changes in light intensity associated with the crepuscular periods act as cues controlling maor rhythmic activity patterns of the species.Item Diel oviposition cycle of Aedes albopictus (Diptera:Culicidae) at Peradeniya, Sri Lanka(1984-85) Karunaratne, S.H.P.P.; Amarasinghe, F.P.The diel oviposition cycle in Aedes albopictus (Skuse) was investigated under natural conditions at a site at Peradeniya, Sri Lanka. The pattern of egg laying demontrated was essentially unimodal, most of the activity occurring between 1300-1900 hrs. with a sharp peak during the hour before sunset (1700-1800 hrs). Oviposition also occurred immediately after sunrise but the level of activity is considered too low to indicate evidence of bimodality in the cycle.Item Ecology of four potential culex vectors(Diptera: Culicidae) of Japanese encephalitis in Kandy, Sri Lanka(1994) Karunaratne, S.H.P.P.; Amarasinghe, F.P.A field studies on the four major potential vectors of Japanese encephalitis in Sri Lanka, i.e., culex tritaeniorynchus Giles, Cx. gelidus Theobald, Cx. pseudovishnui Colless and Cx. fuscocephala Theobald, was done from September 1986 - December 1987 at 4 study the city of Kandy, in the Central Province of Sri Lanka. A total of 73,968 mosquitoes belonging to 10 genera and 45 species were trapped by CDC light traps operated on a weekly basis in a piggery at each site. Mearly 88perc. of light- trapped mosquitoes belong to the above four species. Two population peaks were observed in May - June and October - December, coinciding with the periodicity of monsoonal rains and rice cultivation cycles. Time segregated light trap catches showed that the four species were active throughout the night , with dusk and dawn peaks in Cx. pseudovishnui and Cx. gelidus respectivelyItem The structure and identification of the hairs of the mammals of Sri Lanka(1983) Amarasinghe, F.P.