The Spot Prawn (Pandalus platyceros) have four white spots on the abdominal segments – you can see one of them in the photo near the top of the first segment. A few of these happen to have roe, also.
According to the Monterey Bay Aquarium, “Spot prawns change sex as they grow. They spend the first part of their lives as males, then change into females.”
As with many of the aquatic species at the aquarium, they also make good eatin’.