This has recently been renamed from Polystichum richardii but our take on this species is that it is slightly more finer in the frond than richardii - anyway it probably doesn't matter thats just our observation.
The fern is very hardy and is often found on coastal areas and/or at bush edges. Not found in natural habitat south of lower North Island if that makes sense.
Common names are Shore shield fern or Common shield fern.
Looks like it will get to about 30-35cm tall (we haven't had it here for that very long!), nice looking ground fern