The New Zealand Plant Conservation Network

I have been trying to identify this attractive ground-cover that we have 'inherited'! Chasing through Allen's key without success leads me to the conclusion that it is not a native, and trawling the Web, I wonder whether it is a mountain sandwort Arenaria montana. The leaf form is delicate pinnate, mat-forming, and flowers in late spring. All opinions valued.

Second photo, detailing foliage of ground-cover plant

HI Geoff
I believe this is Sedum 'Peter Pan' or a similar variety.
Cheers
Denise

Hi Geoff, It looks like an Azorella which forms a beautiful mat

Thank you both very much for your communications. With kind thoughts, Geoff Cutfield

Hi Geoff,
I think you have been led up the garden path so to speak; I believe your plant is
Saxifraga x arendsii "White Carpet" or something similar. There is a cultivar named "Peter Pan" which is pink or red and available from Hokonui Alpines. Azorella belongs to the carrot family and your plant though superficially similar in its foliage to Azorella does not.

Thank you too, David. Some independent searching since posting the query has led me to the huge Saxifrage literature. As you have noted, the foliage is very characteristically similar. Of the cream and off-white flowering variants (especially in British sources) there are a number of possibilities. Whatever, it is a very attractive rockery plant and we are enjoying its lovely displays. With kind thoughts, Geoff Cutfield