Classification
Class
Polypodiopsida
Subclass
Polypodiidae
Order
Polypodiales Link
Family
Dryopteridaceae Herter
Genus
Polystichum Roth
 Nomenclature
Scientific Name:
Polystichum lentum (D.Don) T.Moore, Index Fil. 86, 95 (1858)
Synonymy:
  • ≡ Aspidium lentum D.Don, Prodr. Fl. Nepal. 4 (1825)
Lectotype (selected by Fraser-Jenkins et al. 2018): Nepalia [Nepal], Wallich 360, Herb. Hooker., K 001040147 (!online)
Etymology:
From the Latin lentus (tough), a reference to the nature of the frond.
 Recognition

Polystichum lentum has an erect rhizome and narrowly elliptic laminae up to 450 mm long and 95 mm wide, which often bear a single bulbil near the apex of the rachis. The primary pinnae are deeply toothed to about ½ way to the midrib for most of their length, but those near the base of the lamina are often completely divided into a single basal acroscopic secondary pinna (Brownsey & Smith-Dodsworth 2000; Zhang 2012; Zhang & Barrington 2013b).

 Distribution

North Island: Northland.

Altitudinal range: c. 20 m.

Polystichum lentum has been collected once from Onerahi, near Whangārei.

It is a Himalayan species, which occurs naturally in western China, Bhutan, Nepal and north-east India (Zhang & Barrington 2013b).

Polystichum lentum distribution map based on databased records at AK, CHR & WELT. Image: K.Boardman © Landcare Research 2020 CC BY 4.0
Polystichum lentum distribution map based on databased records at AK, CHR & WELT. Image: K.Boardman © Landcare Research 2020 CC BY 4.0
 Habitat

Recorded growing on dumped clay on a clay bank.

 Biostatus
Exotic
 First Record

Brownsey (1981). Voucher WELT P010777, 1980.

 Images
Polystichum lentum. Close up of WELT P010777/B, showing deeply divided primary pinnae and round sori. Image: B. Hatton © Te Papa CC BY-NC 3.0 NZ
Polystichum lentum. Close up of WELT P010777/B, showing deeply divided primary pinnae and round sori. Image: B. Hatton © Te Papa CC BY-NC 3.0 NZ
 Bibliography
Brownsey, P.J.; Perrie, L.R. 2021: Dryopteridaceae. In: Breitwieser, I. (ed.) Flora of New Zealand — Ferns and Lycophytes. Fascicle 31. Manaaki Whenua Press, Lincoln.
Don, D. 1825: Prodromus Florae Nepalensis. J. Gale, London.
Fraser-Jenkins, C.R.; Gandhi, K.N.; Kholia, B.S. 2018: An annotated checklist of Indian pteriodphytes. Part 2. Woodsiaceae to Dryopteridaceae. Bishen Singh Mahendra Pal Singh, Dehra Dun, India.
Moore, T. 1857–1862: Index Filicum. Pamplin, London.