Is the gluteus medius muscle located on the ventral surface of the body? Is the occipitalis muscle located on the ventral surface of the body?
For humans, the answer to both is no.
Ventral and dorsal is another way of saying anterior and posterior. Ventral is the same and anterior and dorsal is the same as posterior.
The gluteal muscles are located on posterior side of the human body with the gluteus medius also extending laterally to the greater trochanter of the femur. The occipitalis muscle is located at the base of the skull, on the posterior side of the human body.