SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f8afa336da94e054658df9771927bb6381d7ffbc12f2bf77bb892275cb81201' 
  AND token = 'Eg3bbX1+TvBMZZSosggLQnXqIWRJFmKi6rsUtrjVbDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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