Classification
 Nomenclature
Scientific Name:
Asplenium lyallii (Hook.f.) T.Moore, Index Fil. 143 (1859)
Synonymy:
  • Asplenium lucidum var. lyallii Hook.f., Bot. Antarct. Voy. II (Fl. Nov.-Zel.) Part II, 33, t. 77 (1854)
  • Asplenium obtusatum var. lyallii (Hook.f.) G.M.Thomson, Ferns New Zealand 74 (1882)
Lectotype (selected by Brownsey & Perrie 2017): Otago, Middle Island [South Island], Dr Lyall, Acheron, March 1850, Herb. Hooker., K 001092556!
  • = Asplenium triste Raoul, Ann. Sci. Nat., Bot. sér. 3, 2: 115 (1844) nom. illeg., non Asplenium triste Kaulf. 1824
  • Asplenium bulbiferum var. triste (Raoul) Hook.f., Bot. Antarct. Voy. II (Fl. Nov.-Zel.) Part II, 34 (1854) nom. illeg.
Holotype: Nouvelle-Zélande [New Zealand], Presqu’île de Banks [Banks Peninsula], Raoul, 1843, P 04022106! (see Brownsey 1979)
  • = Asplenium anomodum Colenso, Trans. & Proc. New Zealand Inst. 15: 309 (1883)
  • Asplenium lucidum var. anomodum (Colenso) Cheeseman, Man. New Zealand Fl. 991 (1906)
  • Asplenium obtusatum var. anomodum (Colenso) Domin, Biblioth. Bot. 20(85): 101 (1913)
Lectotype (selected by Brownsey 1979): Norsewood, Hawkes Bay, Herb. Colenso, WELT P002813 (except piece at top right)!
Etymology:
Named in honour of David Lyall (1817–1895), surgeon and naturalist on the Antarctic Voyage of James Clark Ross in HMS Erebus and Terror (1839–1843), and who also visited New Zealand during the voyage of the Acheron, 1847–1851.
Vernacular Name(s):
Lyall's spleenwort
 Description

Terrestrial or rupestral ferns. Rhizomes erect or short-creeping, bearing scales. Rhizome scales narrowly ovate, 8–25 mm long, 1–4.5 mm wide, brown, clathrate.   Fronds 12–900 or rarely up to 1160 mm long. Stipes 4–400 mm long, pale brown abaxially and proximally, green adaxially and distally, bearing abundant narrowly ovate scales with filiform apices. Rachises green or sometimes brown abaxially, bearing abundant scales. Laminae 1–2-pinnate, narrowly ovate or ovate or elliptic, narrowed to a short pinnatifid or rarely undivided terminal segment with serrate margins similar to or more deeply incised than the primary pinnae; laminae 8–550 or rarely to 770 mm long, 5–230 mm wide, dark shiny green on adaxial surface and paler on abaxial surface or dull grey-green on both surfaces, herbaceous or coriaceous, bearing scales abaxially and sometimes adaxially, lacking hairs. Primary pinnae in 1–18 pairs below an undivided or pinnatifid apical segment, not overlapping; proximal pinnae ovate or narrowly ovate, those at mid-lamina narrowly ovate or narrowly oblong; the longest pinnae at or below the middle, 2–155 mm long, 1.5–60 mm wide; pinna apices obtuse or acute or acuminate, margins serrate, bases stalked; proximal pinnae bearing 1–6 pairs of secondary pinnae in the proximal half, or partially lobed or divided acroscopically, or occasionally not divided or lobed (on smallest fronds). Secondary pinnae ovate to elliptic, the longest 7–45 mm long, 4–16 or rarely up to 25 mm wide; apices obtuse, margins entire or serrate, bases stalked. Sori away from margins; indusia 3–14 mm long or rarely only 1 mm long in very small plants, straight; free margins of indusia entire. Mean spore size 40–54 μm long, 27–35 μm wide; perispores prominently winged and ridged.

 Recognition

Asplenium lyallii is an extremely variable species showing a wide range of frond size, colour and dissection. Plants growing in sheltered lowland habitats tend to produce large 2-pinnate fronds with dark glossy-green adaxial surfaces, whereas plants in exposed situations at high altitudes have much smaller 1-pinnate fronds that are dull grey-green on both surfaces. Usually the proximal pinnae are at least lobed or divided acroscopically, but in very small plants the pinnae can be undivided and lacking lobes. Small 1-pinnate fronds can be confused with A. lepidotum or small fronds of A. oblongifolium and A. obtusatum, but A. lyallii has larger spores than the other species. The stipe scales of A. oblongifolium are also narrower, with longer filiform apices, and scales are absent from the adaxial pinna surfaces. Plants of A. obtusatum have generally thicker fronds and are strictly coastal in habitat.

 Distribution

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

South Island: Western Nelson, Sounds-Nelson, Marlborough, Westland, Canterbury, Otago, Southland, Fiordland.

Chatham Islands, Stewart Island.

Altitudinal range: 0–1400 m.

Asplenium lyallii occurs in the North Island on the west coast from Mt Karioi to south Taranaki, and on the eastern side of the island from the Gisborne and Hawke’s Bay ranges through the Ruahine Ranges and along the east coast to Wellington. It grows in coastal, lowland, montane, and subalpine areas from near sea level up to 1300 m on Mt Maungapōhatu, Gisborne. In the South Island it is largely confined to eastern districts, extending from north-west Nelson through Marlborough, Canterbury, coastal Otago and Southland into Fiordland and south Westland. It occurs in coastal, lowland, montane, and subalpine areas, ranging from sea level up to 1400 m in north-west Nelson, and also extends to Stewart Island and the Chatham Islands.

There are doubtful records from Northland, which need confirmation. One, which is definitely a specimen of A. lyallii, was said to be collected from Butler Bay, Mangōnui (WELT P009970) but grown on in cultivation and therefore possibly confused with another collection. The second came from Puketi Forest (AK 307201) but is sterile and could possibly be a hybrid.

 Habitat

Asplenium lyallii is a terrestrial fern found frequently on limestone, marble, or calcareous mudstone or sandstone, but also on greywacke, and on andesite and basalt in the western Waikato. It grows under open broadleaved, beech and kānuka forest, amongst the roots of Corynocarpus laevigatus, with Phormium on coastal cliffs, in coastal scrub, among coastal rocks, and on sand. At higher altitudes it occurs on mossy boulders under forest, on river banks, or in the open on rocky ground, on banks, on cliffs, in rock crevices, under overhangs and around caves.

 Biostatus
Indigenous (Endemic)
 Cytology
 Notes

Allan (1961) treated this species as A. anomodum Colenso but observed in the supplementary notes that the name A. lyallii (Hook.f.) T.Moore, based on A. lucidum var. lyallii Hook.f., would take precedence if accepted at the species level. However, Asplenium lucidum G. Forst. is a later homonym of A. lucidum Burm.f. and therefore illegitimate. The names A. lucidum var. lyallii Hook. and A. lucidum var. anomodum are incorrectly formed and cannot be used. Nevertheless, the varietal epithets are legitimate and var. lyallii Hook.f. can be used as the basionym for A. lyallii.

Brownsey (1978) showed that Asplenium triste, which had previously been thought to be a synonym of A. bulbiferum, was actually a synonym of A. lyallii. It is the earliest published name for the latter species (Raoul 1844), but is illegitimate because of an earlier homonym. The combination A. bulbiferum var. triste (Raoul) Hook.f. is therefore also illegitimate.

Analysis of low-copy nuclear DNA sequences suggests that A. lyallii is an allopolyploid species derived from A. hookerianum and either A. oblongifolium or A. obtusatum (Shepherd et al. 2008), although the subsequently described A. lepidotum should also be considered (Perrie & Brownsey 2016).

 Bibliography
Brownlie, G. 1958: Chromosome numbers in New Zealand ferns. Transactions of the Royal Society of New Zealand 85: 213–216. [as Asplenium anomodum Colenso; Asplenium lucidum var. lyallii Hook.f.]
Brownsey, P.J. 1977a: Asplenium hybrids in the New Zealand flora. New Zealand Journal of Botany 15: 601–637.
Brownsey, P.J. 1977b: A taxonomic revision of the New Zealand species of Asplenium. New Zealand Journal of Botany 15(1): 39–86.
Brownsey, P.J. 1978: A note on the identity of Asplenium triste Raoul. New Zealand Journal of Botany 16: 281–282.
Brownsey, P.J. 1979: Type material in the herbarium of the National Museum of New Zealand (WELT). I. New Zealand pteridophytes. National Museum of New Zealand Records 1: 243–269.
Brownsey, P.J. 1985: Asplenium chathamense - a new fern species from the Chatham Islands, New Zealand. New Zealand Journal of Botany 23(1): 135–140.
Brownsey, P.J.; Perrie, L.R. 2018: Aspleniaceae. In: Breitwieser, I.; Wilton, A.D. (ed.) Flora of New Zealand — Ferns and Lycophytes. Fascicle 18. Manaaki Whenua Press, Lincoln.
Cheeseman, T.F. 1906: Manual of the New Zealand Flora. Government Printer, Wellington.
Colenso, W. 1883: A description of four new ferns from our New Zealand forests. Transactions and Proceedings of the New Zealand Institute 15: 304–310.
de Lange, P.J.; Heenan, P.B.; Rolfe, J.R. 2011: Checklist of vascular plants recorded from Chathams Islands. Department of Conservation, Wellington Hawke's Bay Conservancy.
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]
Domin, K. 1913: Beiträge zur Flora und Pflanzengeographie Australiens. Bibliotheca Botanica 20(85): 1–239.
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.
Moore, T. 1857–1862: Index Filicum. Pamplin, London.
Perrie, L.R.; Brownsey, P.J. 2016: Asplenium lepidotum, a new fern species from New Zealand allied to Asplenium oblongifolium and Asplenium obtusatum. New Zealand Journal of Botany 54(3): 377–391.
Raoul, E. 1844: Choix de plantes de la Nouvelle-Zélande. Recueillies et décrites par M.E. Raoul. Annales des Sciences Naturelles; Botanique sér. 3, 2: 113–123.
Shepherd, L.D.; Perrie, L.R.; Brownsey, P.J. 2008: Low-copy nuclear DNA sequences reveal a predominance of allopolyploids in a New Zealand Asplenium fern complex. Molecular Phylogenetics and Evolution 49: 240–248.
Thomson, G.M. 1882: The ferns and fern allies of New Zealand. Robertson, Melbourne.