SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99be8cfafa3551c3234be918cdfb7841679cbbaf869ee2bd67a9c3ea3e532d9d' 
  AND token = 'g03BtYdvBmjrjB/0MO26zdhpx/P3XiXuUZhytYmCp/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00101

JSON explain

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