SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a683088480497837f7441e5643b6aa5ec7c147fefe96f534898b6c5f285ced19' 
  AND token = 'Zh+hOyrc9UpOVPhVHp9liX+g7dyBD2RO+wP63+zFza4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}