Figure 10. Gradual evolution of egg cluster lays in experimentally raised Lymnaea schirazensis and Galba truncatula: A–O) L. schirazensis: note trend to kidney shape in early lays (E–K) and final trend to banana-shape in late trends (L–O); only in very early lays, when shape is still round-oval (A, B) and may sometimes become elongate (C, D), it can be confused with clusters of G. truncatula. P–Z) G. truncatula: note general trend to round-oval shape (P–R, V–X) and occasional variation to elongate shape (S–U, Y, Z).

Materials of L. schirazensis from strains originally collected in Xalpatlaco, Mexico (A, B, F, I, J), Jiutepec, Mexico (C), Albufera of Valencia, Spain (D, E, G, L, O), Tiba, Egypt (H), Escuela Obrego, Mexico (K). Materials of G. truncatula from strains originally collected in Qued Tiout, Marrakesh, Marocco (P–T, Y, Z) and Albufera of Valencia, Spain (U–X). Scale bar = 2 mm.