Final answer:
The large opening between the pelvic fins or claspers is called the pelvic outlet. It is located between the ischium and pubic regions of the bony pelvis. The two parts of the pubis that contribute to the formation of this opening are the ischial tuberosity and the inferior pubic ramus.
Step-by-step explanation:
The large opening between the pelvic fins or claspers is called the pelvic outlet. It is located between the ischium and pubic regions of the bony pelvis. The two parts of the pubis that contribute to the formation of this opening are the ischial tuberosity and the inferior pubic ramus.