SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d40913399df1d68b903df3c678ca409411e5974c8972e051c92cfed6a7e901c' 
  AND token = 'tGtMhBibBigezpvZoUMrN8+4xYVSkd+ytixNqoigERc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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