SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '169f4685f0b454359fcff77c8e5dad4119d0bba0a53420655f8aa66f82ce7fd0' 
  AND token = 'z19dc07X7ANxZcMZYR/2j2VkpeChd9IqogViS+QDvLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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