caa a22 4500 388112549 CHVBK 20180307125357.0 cr unu---uuuuu 161130e199901 xx s 000 0 eng 10.1017/S0022149X99000074 doi S0022149X99000074 pii (NATIONALLICENCE)cambridge-10.1017/S0022149X99000074 McCarthy A.M. Division of Life Sciences, King's College London, University of London, Campden Hill Road, London, W8 7AH, UK Photoperiodic cercarial emergence patterns of the digeneans Echinoparyphium recurvatum and Plagiorchis sp. from a mixed infection in Lymnaea peregra [Elektronische Daten] [A.M. McCarthy] Photoperiodic emergence patterns of the cercariae of two digeneans, Echinoparyphium recurvatum (Echinostomatidae) and Plagiorchissp. (Plagiorchiidae), were studied experimentally using a photoperiodic regime of 12 h light: 12 h dark at a constant 18°C. In single species infections of the first intermediate host snail Lymnaea peregra, the cercariae of E. recurvatum emerged exclusively during the light phase and those of Plagiorchis sp. emerged exclusively during the dark phase. In double infections, each species retained its own discrete photoperiodic emergence pattern. This result demonstrates the absence of interference between the mechanisms responsible for the photoperiodic emergence pattern of each species. A degree of interference between the two parasites in double infections of L. peregra was evident. The presence of E. recurvatum significantly reduced the number of Plagiorchis sp. cercariae emerging in a 24 h period and also delayed the mean peak emergence time of Plagiorchissp. cercariae by 2 h. This result is consistent with the well documented antagonistic effect that the redial stages of echinostomes are known to have against the sporocysts of other digeneans within the same host mollusc. Cambridge University Press Journal of Helminthology Cambridge University Press 73/1(1999-01), 59-62 0022-149X 73:1<59 1999 73 JHL https://doi.org/10.1017/S0022149X99000074 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0022149X99000074 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- McCarthy A.M. Division of Life Sciences, King's College London, University of London, Campden Hill Road, London, W8 7AH, UK NATIONALLICENCE 773 0- Journal of Helminthology Cambridge University Press 73/1(1999-01), 59-62 0022-149X 73:1<59 1999 73 JHL CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge