Fig. 5 Cotylea and Acotylea general male system organization. a Pseudobiceros with forward directed male structures and mucous glands. b Imogine with backward directed male structures. c in Polycladida phylogeny and evolution: integrating evidence from 28S rDNA and morphology

Fig. 5 Cotylea and Acotylea general male system organization. a Pseudobiceros with forward directed male structures and mucous glands. b Imogine with backward directed male structures. c Cestoplana with perpendicular to forward directed male structures and mucous glands. d Cestoplana specimens during simultaneous hypodermic impregnation