[Distribution of argentophilic structures in two strigeid cercariae, Cotylurus brevis Dubois et Rausch, 1950 and Apatemon (A.) minor Yamaguti, 1933].

Two furcocercariae respectively Colylurus brevis Dubois et Rausch, 1950 from Segmentina nitida and Apatemon (A.) minor Yamaguti, 1933 from Gyraulus acronicus were studied and identified morphologically. Ciliary papillae distribution was studied after staining with silver nitrate solution and compared with that of cercariae known in the same genus. Colylurus brevis was compared to Cotylurus lutzi Basch, 1969 and Cotylurus sp. Kruger, 1978. Apatemon (A.) minor was compared to Apatemon sp. Kruger, 1978, Apatemon graciliformis Szidat, 1928, and Cercaria 1 Richard, 1971. Cercariae of the genus Cotylurus and Apatemon were easily identified from the number and distribution of acetabular papillae: 4 SI + 6 SII in Cotylurus and 3 SI + 3 SII in Apatemon. These characteristics further enabled the identification of a cercaria belonging to the genus Diplostomum since all the carcariae studied in this genus have 3 SI + 6 SII.