Nomenclature
Scientific Name:
Loxogramme dictyopteris (Mett.) Copel., Univ. Calif. Publ. Bot. 14: 369 (1929)
Synonymy:
  • Polypodium dictyopteris Mett., Ann. Sci. Nat. Bot. sér. 4, 15: 77 (1861)
  • Anarthropteris dictyopteris (Mett.) Copel., Gen. Fil. 218 (1947)
Lectotype (selected by Brownsey & Perrie 2012): Plate 409 in Icones Plantarum (Hooker 1841).
  • = Dictyopteris lanceolata J.Sm., J. Bot. (Hooker) 4: 64 (1841) nom. nud.
  • Anarthropteris lanceolata (J.Sm.) L.B.Moore in Allan, Fl. New Zealand 1, 1010 (1961) nom. illeg.
  • = Dictymia lanceolata Hook.f., Bot. Antarct. Voy. II (Fl. Nov.-Zel.) Part II, 43 (1854)
  • Polypodium cunninghamii Hook., Gard. Ferns t. 30 (1862) nom. nov. pro Dictymia lanceolata Hook.f. 1854
  • Anarthropteris lanceolata (J.Sm. ex Hook.f.) Pic.Serm., Webbia 29: 13 (1975)
Lectotype (selected by Brownsey & Perrie 2012): New Zealand, J.D. Hooker, K 000501466!
Etymology:
From the Greek dictyon (a net), and pteris (a fern), in reference to the venation.
Vernacular Name(s):
lance fern
 Description

Low epiphytic or rupestral ferns. Rhizomes erect, scaly, bearing proliferous roots. Rhizome scales clathrate, narrowly ovate, 2–7 mm long, 0.5–1 mm wide, squarrose, brown, entire. Stipes indistinct from lamina, not obviously articulated to rhizome. Fronds undivided, narrowly elliptic to narrowly obovate, 40–360 mm long, 4–35 mm wide; apex acuminate or sometimes acute; margins entire or rarely slightly toothed; base attenuate to an indistinct winged stipe; adaxial surface dark green; abaxial surface slightly paler; herbaceous to coriaceous; glabrous except for widely scattered scales at the base. Costa prominent on adaxial surface; veins reticulate; areoles without free included veinlets; hydathodes absent. Sori round or slightly elongate, 3–7 mm long, partly impressed into lamina forming low bulges on adaxial surface, in 1 row either side of the costa, closer to costa than margin, usually confined to distal half of frond; paraphyses present as very narrow clathrate scales c. 3 cells wide; exindusiate.

 Recognition

This species is easily recognised by its undivided fronds, and large, exindusiate, round or slightly elongate sori. The proliferous roots, giving rise to new plants at intervals, can be confused for a creeping rhizome, but the species has an erect rhizome, which distinguishes it from Pyrrosia species and juvenile plants of Lecanopteris species. It can be further distinguished from Pyrrosia by its glabrous lamina, and from Lecanopteris by its lack of free, included veinlets in the areoles.

Occasional aberrant fronds are found, either crested at the apices or with the lamina divided into short, lateral segments.

 Distribution

North Island: Northland, Auckland, Volcanic Plateau, Gisborne, Taranaki, Southern North Island.

South Island: Western Nelson, Sounds-Nelson, Westland, Canterbury.

Chatham Islands.

Altitudinal range: 0–1000 m.

Loxogramme dictyopteris is common throughout coastal and lowland regions of the North Island, extending locally into montane areas. It occurs from near sea level, up to 675 m in Erua Forest, and 1000 m on Mt Pihanga near Lake Taupō, but is uncommon in the higher areas of the Volcanic Plateau and Gisborne. In the South Island it is mostly confined to coastal and lowland areas of the Marlborough Sounds and Nelson, growing up to 450 m near Punakaiki, and extending as far south as Lake Kaniere on the west coast, and Banks Peninsula on the east coast. It also reaches the Chatham Islands.

 Habitat

A low epiphyte on trunks and fallen logs, or on acidic and calcareous rocks and banks, in damp shaded parts of coastal and lowland broadleaved forest; sometimes in shaded hollows of open scoria. It covers large areas on trunks or rocks owing to its proliferous roots, but rarely occurs far above ground level. It often wilts conspicuously in dry weather.

 Biostatus
Indigenous (Endemic)
 Cytology

n = 37 (Brownlie 1958, as Anarthropteris dictyopteris).

 Notes

This species has a complex taxonomic history, documented by Pichi Sermolli (1975). The earliest name, Polypodium attenuatum R.Br., used by Richard (1832), was a misidentification for what is now known as Dictymia brownii (Wikstr.) Copel., but was in any case illegitimate because of a previously published homonym. The species was first validly described as Dictymia lanceolata by Hooker (1855), but when transferred to Loxogramme, Copeland (1929) had to base his new combination on a later name, Polypodium dictyopteris Mettenius (1861), because the combination based on D. lanceolata was pre-occupied in Loxogramme. However, when he transferred it again to his new genus Anarthropteris, Copeland (1947) incorrectly used the combination Anarthropteris dictyopteris, overlooking the earlier binomial, Dictymia lanceolata. Moore (in Allan 1961) established the correct combination, Anarthropteris lanceolata, but attributed the species name incorrectly to J. Smith, rather than J.D. Hooker. This error was corrected by Pichi Sermolli (1975), who established the correct name, Anarthropteris lanceolata (J.Sm. ex Hook.f.) Pic.Serm. However, when treated in Loxogramme, the correct name is L. dictyopteris (Mett.) Copel. (Kreier & Schneider 2006).

 Bibliography
Brownlie, G. 1958: Chromosome numbers in New Zealand ferns. Transactions of the Royal Society of New Zealand 85: 213–216.
Brownsey, P.B.; Parris, B.S.; Perrie, L.R. 2021: Polypodiaceae. In: Breitwieser, I. (ed.) Flora of New Zealand — Ferns and Lycophytes. Fascicle 1. Manaaki Whenua Press, Lincoln.
Brownsey, P.J.; Given, D.R.; Lovis, J.D. 1985: A revised classification of New Zealand pteridophytes with a synonymic checklist of species. New Zealand Journal of Botany 23(3): 431–489.
Brownsey, P.J.; Perrie, L.R. 2012: Taxonomic notes on the New Zealand flora: lectotypes and excluded taxa in the fern family Polypodiaceae. New Zealand Journal of Botany 50: 179–184.
Brownsey, P.J.; Perrie, L.R. 2015: Polypodiaceae (excluding Notogrammitis). In: Breitwieser, I; Heenan, P.B.; Wilton, A.D. (ed.) Flora of New Zealand — Ferns and Lycophytes. Fascicle 1. Manaaki Whenua Press, Lincoln.
Copeland, E.B. 1929: Pteridophyta Novae Caledoniae. University of California Publications in Botany 14: 353–369.
Copeland, E.B. 1947: Genera Filicum. Chronica Botanica Co., Waltham, Mass.
de Lange, P.J.; Rolfe, J.R.; Barkla J.W.; Courtney, S.P.; Champion, P.D.; Perrie, L.R.; Beadel, S.N.; Ford, K.A.; Breitwieser, I.; Schönberger, I.; Hindmarsh-Walls, R.; Heenan, P.B.; Ladley, K. 2018: Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series No. 22. [Not Threatened]
de Lange, P.J.; Rolfe, J.R.; Champion, P.D.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Norton, D.A.; Hitchmough, R.A. 2013: Conservation status of New Zealand indigenous vascular plants, 2012. New Zealand Threat Classification Series 3. Department of Conservation, Wellington. [Not Threatened]
Hennipman, E.; Veldhoen, P.; Kramer, K.U. 1990: Polypodiaceae. In: Kramer, K.U.; Green, P.S. Pteridophytes and gymnosperms. Vol. 1. In: Kubitzki, K. (ed.) The Families and Genera of Vascular Plants. Springer-Verlag, Berlin.
Hooker, J.D. 1854–1855: The Botany of the Antarctic Voyage of H.M. Discovery Ships Erebus and Terror, in the years 1839–1843, under the command of Captain Sir James Clark Ross. II. Flora Novae-Zelandiae. Part II. Flowerless plants. Lovell Reeve, London.
Hooker, W.J. 1841: Icones Plantarum. Vol. 5. Hippolyte Baillière, London.
Hooker, W.J. 1862: Garden Ferns. Lovell Reeve, London.
Kramer, K.U.; Green, P.S. 1990: Pteridophytes and gymnosperms. Kubitzki, K. (ed.) The Families and Genera of Vascular Plants. Vol. 1. Springer-Verlag, Berlin. [as Anarthropteris lanceolata (J.Sm.) L.B.Moore]
Kreier, H.-P.; Schneider, H. 2006: Reinstatement of Loxogramme dictyopteris, based on phylogenetic evidence, for the New Zealand endemic fern, Anarthropteris lanceolata (Polypodiaceae, Polypodiidae). Australian Systematic Botany 19: 309–314.
Large, M.F.; Braggins, J.E. 1991: Spore atlas of New Zealand ferns and fern allies. SIR Publishing, Wellington. [as Anarthropteris lanceolata (J.Sm. ex Hook.f.) Pic.Serm.]
Mettenius, G.H. 1861: Filices Novae Caledoniae a Cl. Viellard collectae. Annales des Sciences Naturelles; Botanique sér. 4, 15: 55–91.
Pichi Sermolli, R.E.G. 1975: Fragmenta Pteridologiae V. Webbia 29: 1–16.
Richard, A. 1832: Essai d'une Flore de la Nouvelle Zélande. In: Dumont d'Urville, J. Voyage de découvertes de l'Astrolabe. Botanique. Tastu, Paris. [as Polypodium attenuatum sensu A.Rich.]
Smith, J. 1841: An arrangement and definition of the genera of ferns, with observations on the affinities of each genus. Journal of Botany (Hooker) 4: 38–70.