Check the bay scallops for any remaining side muscles and remove them if necessary.
Squeeze citrus juices into a large bowl. Add scallops to the bowl with a dash of salt. Place in refrigerator for approximately four hours until the bay scallops are opaque all the way through.
Make the salsa. Place diced avocado in a bowl with lime juice, salt, and olive oil. Add some onion, serrano chili, and cilantro. Add segmented mandarin oranges and mix all together.
Remove scallops from the refrigerator. Add onion, serrano chili, and cilantro to the chilled scallops and stir together.
Scoop scallops into serving glasses. Pour in a little ceviche juice over them. Spoon salsa on top. Drizzle with olive oil. Garnish with lime wedge and cilantro.