(C) anterolateral view of pelvic girdle. il, iliac region (dark purple); im, intermuscular bone (light purple); is, ischial region of puboischiadic plate (tan); pf, pelvic fin (blue); pu, pubic region of puboischiadic plate (tan); sr, sacral ribs (dark purple). Vertebrae numbers 6,7,8 designate position from skull, (D) close-up image of acetabular symphysis, (E) close up image of obturator foramen, of.