Dryopteris affinis (Lowe) Fraser-Jenk.
Rhizomes stout, erect, often covered in dead stipe bases. Stipes 10-40 cm long, pale brown. Stipes and rachises densely covered in orange-brown scales. Laminae elliptic or narrowly elliptic, 2-pinnate, 30-125 × 15-30 cm, glossy when fresh, yellowish green. Primary pinnae in 25-50 (or more) pairs, narrowly triangular or ± oblong, tapering at apices, sessile, 8-15 × 2-3 cm, with a darkish patch near junction with rachis when fresh. Secondary pinnae in 15-30 pairs, oblong, adnate or decurrent on pinna midrib, obliquely truncate at apices, ± entire or toothed only at apices, to 15 × 7 mm; secondary pinnae on the basal pair of primary pinnae ± equal in length either side of midrib. Sori round, 1-5 pairs on each secondary pinna, often confined to upper pinnae, covered by reniform indusia which are rolled under sporangia when young.
N.: S. Auckland (Atiamuri), Wellington City; S.: Canterbury (Christchurch), Otago (Dunedin).
Europe, Asia 1980
Grassy banks, streamsides, open forest.
Lovis, J. D., Canterbury Bot. Soc. J. 14 : 1-4 (1980), discussed more fully the differences between D. affinis and D. filix-mas. D. affinis is an apomictic sp., with 4 levels of ploidy known in the N. Hemisphere; plants from Wellington are triploid (Brownsey, P. J., unpubl.). D. affinis is generally less common in N.Z. than D. filix-mas, except in Dunedin where it is the predominant fern in the Town Belt. Occasional hybrids with D. filix-mas (named D. × tavellii Rothm.) also occur in this locality. D. affinis has previously been known as either D. borreri or D. pseudomas. A selected form with forked pinnae, known as var. polydactyla, is commonly grown in gardens and occasionally escapes.
