SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '240a98caad71d21d3ea9b708eaa787a16d553cbc69f2620113170fd40819f3ce' 
  AND token = 'tpt9ZmgJ6kF0OyFceExwavockxJAJ5MsCi4kBHQQk0k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}