Polystichum setiferum NS 8543 23Sep2018 MP

Note the big “thumbs” and obtuse angle at the base of the pinules.

Polystichum setiferum NS 8543 23Sep2018 MP

Polystichum setiferum 15Feb2017 NS7155 MP

Polystichum setiferum 15Feb2017 NS7155 MP

Note the acute angle of the base of the pinule.

Polystichum aculeatum NS 8543 23Sep2018 MP

The fronds are quite slender.

Polystichum aculeatum NS 8543 23Sep2018 PW

You can see through between the pinules and the rachis.

Polystichum aculeatum NS 8543 23Sep2018 PW

Polystichum aculeatum NS7550 25May2018 MP

Polystichum aculeatum NS 8543 23Sep2018 mp

Polystichum aculeatum NS8543 23Sep2018 MP

Polystichum species - Shield-ferns

There are two Polystichum species.

Polystichum setiferum Soft Shield Fern has pinules with obvious, showy, acuminate teeth. There are big, prominent distal-facing 'thumbs' which lie along the midrib with no gap and angle between the base of the pinule and its proximal edge is clearly obtuse.

Because the pinule 'sits' on the midrib and the angle 'leans back', think of settee (as an aid to setiferum).

Polystichum aculeatum Hard Shield Fern has smaller pinule teeth and no prominent 'thumbs' and base of pinule veering away from the midrib. The angle between pinule base and proximal edge is clearly acute. The 'acute' angle prompts the epithet aculeatum.

Of the two Polystichum species, this is the more common one in Lanarkshire.