quiz question

[suequiz]

I have an unusual question on a gardening question to try and answer.
Philteris vulgaris is a plant with a sessile, crawling or prostrate habit, - discuss.
As far as I can find Philteris vulgaris is not really a plant name. I am told there is a clue in what the quiz is in aid of which is Winster Village Shop. I thought guy or gal running the shop may be named Phil Teris but this does not seem to be the case. Does anyone have any bright ideas as to what the answer may be please?
Many thanks Sue