Fig. 6

Frame-grab images from Additional file 2: Movie SM1 with structures of interest labeled. a Disseta palumbii. b Mesorhabdus gracilis. c Heterostylites longicornis. d Heterorhabdus subspinifrons. Black dotted circles identify the approximate area, and white dashed lines identify the exact boundaries, of the labeled characters. See abbreviations list and Table 1 for muscle names and abbreviations