Asplenium

Hart's tongue fern Asplenium scolopendrium, from here.

Belongs within: Pteridales.

Asplenium, the spleenworts, is a large cosmopolitan genus of ferns: some species are even found in Arctic or arid habitats (Kramer & Viane 1990). Species of this genus are very diverse in superficial appearance, including species with much divided fronds, undivided fronds and even aquatic rheophytes. However, attempts to subdivide Asplenium have generally not been successful due to variation being fairly continuous.

Characters (from Kramer & Viane 1990): Terrestrial, epilithic, or epiphytic ferns of small to medium, rarely to large size; stem short and (sub)erect or sometimes long and creeping, dictyostelic, with well-developed cortical sclerenchyma, bearing non-peltate, clathrate, entire, marginally fimbriate, or glandular, rarely ciliate, dorsally glabrous scales, these sometimes iridescent. Leaves clustered to remote; petiole non-articulate, almost wanting to well-developed, usually smooth when mature, usually with paleae at base, often hairy and glandular; often dark and sclerotic and then glabrous, adaxially usually flattened to sulcate, typically with two C-shaped to elliptic vascular bundles back to back joining above the base to near the apex of the petiole to form one X-shaped bundle. Lamina very variable, simple or lobed, more often once or twice pinnate, occasionally more strongly dissected, to quadripinnate, anadromous, often truncate at base, thinly membranous to coriaceous, rarely somewhat dimorphic; surface rarely completely glabrous, often with minute uniseriate glandular hairs and slightly scaly; rachis like petiole but with smaller scales, often also dark-sclerotic: proliferous buds often present on rachis (on pinnae and sometimes on petiole), usually borne singly. Pinnae (if any) usually shortly petiolulate to sessile, non-articulate, simple to variously dissected; upper pinnae, pinnules, etc. usually gradually reduced and confluent; conform terminal pinna only present in some simply pinnate species. Ultimate free divisions of very variable size and shape, usually sessile with rounded to cuneate base, rarely decurrent, never surcurrent, sometimes pseudodimidiate or dimidiate, usually costate; edge rarely entire, often crenate-serrate, to pinnatifid, lobes sometimes bifid. Rachises of secondary order (and costae) adaxially grooved, the groove then like that of primary pinnae, or often convex in middle, continuous with that on rachises of different order or rarely not; costae adaxially flat to convex or sulcate. Ultimate lobes not rarely narrow and uninerval. Axes scantily scaly, inconspicuously hairy or glandular. Veins anadromous, rarely isodromous (sometimes basiscopic veins absent), free and pinnate or forked, rarely sparingly to fully reticulate or loop-connected at their ends; free included veinlets always absent. Vein-ends thickened behind margin; margin occasionally sclerotic. Sori single, dorsal on veins, often only on an anterior vein branch but sometimes also on posterior branch of an adjacent veinlet or alternately on anterior and posterior branches and then approximate in pairs. Indusium attached to side of vein, usually long and narrow and with free, tapering ends; occasionally sori very short and submarginal and indusium then at its lateral ends often fused with lamina to form a pouch-like structure; when sori face each other in pairs, indusia open against each other and sori then seemingly confluent at full maturity; rarely sori following vein network and here and there back-to-back or branched, or exindusiate and linear. Sporangia long-stalked, most of stalk uniseriate, eglandular; annulus vertical, interrupted by stalk; stomium well-developed, of several elongate cells, passing into bow. Spores monolete, usually ellipsoid; perispore prominent, consisting of thin basal layer (inner perispore) pressed against exospore, this inner perispore bearing rod-like (sometimes forking) structures (middle perispore) sustaining outer perisporal layer. Middle and outer variously developed, outer layer often (partly) perforated and/or thrown into variously shaped ridges or into spines. Gametophyte prothallia of cordate or elongate-cordate type.

Asplenium
    |--A. scolopendrium YM03
    |--+--A. bulbiferum PB04
    |  `--A. hookerianum PB04
    |--+--A. ritoense YM03
    |  `--A. wrightii YM03
    |--+--A. flaccidum PB04
    |  |    |--A. f. ssp. flaccidum PB04
    |  |    `--A. f. ssp. haurakiense PB04
    |  `--A. lamprophyllum PB04
    |--+--A. ensiforme Wallich ex Hooker & Greville 1828 YM03, I88
    |  |    |--A. e. var. ensiforme I88
    |  |    `--A. e. var. stenophyllum I88
    |  `--+--A. yoshinagae Makino 1900 YM03, I88 (see below for synonymy)
    |     `--+--A. pseudo-wilfordii YM03
    |        `--A. wilfordii YM03
    |--+--A. lyallii PB04
    |  |--A. oblongifolium PB04
    |  |--A. obtusatum PB04
    |  |    |--A. o. ssp. obtusatum PB04
    |  |    `--A. o. ssp. northlandicum PB04
    |  `--A. scleroprium PB04
    |--+--A. incisum YM03
    |  |--A. sibiricus YM03
    |  |--+--A. normale Don 1825 YM03, I88
    |  |  `--A. oligophlebium YM03
    |  |--+--A. serelii YM03
    |  |  `--A. tenuicaule YM03
    |  `--+--A. trichomanes Linnaeus 1753 YM03, I88
    |     `--A. tripteropus YM03
    `--A. sect. Thamnopteris YM03
         |--+--A. australasicum YM03
         |  |--A. nidus Linnaeus 1753 YM03, I88 (see below for synonymy)
         |  `--A. setoi YM03
         `--+--+--A. griffithianum Hooker 1854 YM03, I88
            |  `--A. prolongatum YM03
            `--+--A. antrophyoides YM03
               |--A. phyllitidis Don 1825 YM03, I88 [=Thamnopteris nidus var. phyllitidis (Don) Bedd. 1883 I88]
               `--+--A. antiquum YM03
                  `--A. cymbifolium YM03

Asplenium incertae sedis:
  A. abscissum L54
  A. aethiopicum M06
  A. auritum J87
  A. bullatum Wallich ex Mett. 1859 I88
  A. capillipes Makino 1903 I88
  A. caudatum A27
  A. ceterach PT98
  A. chathamense PB04
  A. cheilosorum Kunze ex Mett. 1859 [incl. A. heterocarpum Wallich ex Hooker 1860] I88
  A. clutei J87
  A. colensoi [=A. hookerianum var. colensoi Moore 1858] C49
  A. commutatum L54
  A. dalhousiae Hooker 1837 (see below for synonymy) I88
  A. excisum Presl 1851 I88
  A. exiguum Bedd. 1863 [incl. A. fontanum] I88
  A. falcatum [incl. A. adiantioides (Linnaeus) Christensen 1905] C49
  A. finlaysonianum Wallich ex Hooker 1854 [=Hemidictyum finlaysonianum (Wallich) Moore 1857] I88
  A. flabellifolium A27
  A. harpeoides L54
  A. juglandifolium SS04
  A. laciniatum Don 1825 I88
  A. lucidum A27
  A. magellanicum M03
  A. marinum G60
  A. monanthes J87
  A. multifidum M03
  A. myriophyllum J87
  A. nitidum Swartz 1806 I88
  A. obliquissimum (Hayata) Sugimoto & Kurata 1959 (see below for synonymy) I88
  A. platyneuron SL05
  A. praemorsum J87
  A. radicans J87
  A. resilens J87
  A. richardi A27
  A. ruta-muraria Linnaeus 1753 I88
  A. septentrionale (Linnaeus) Hoffmann 1795 I88
  A. serra J87
  A. tenuifolium Don 1825 I88
  A. trapezoides D03
  A. unilaterale de Lamarck 1786 I88
  A. varians Wallich ex Hooker & Greville 1829 I88
  A. viride Hudson 1762 I88

Nomina nuda: Asplenium bilobum Squinabol 1889 S89
             Asplenium forsterianum Colenso 1845 C45

Asplenium dalhousiae Hooker 1837 [=Ceterach dalhousiae (Hooker) Christensen 1905; incl. A. alternans Wallich ex Hooker 1860] I88

Asplenium nidus Linnaeus 1753 YM03, I88 [=Neottopteris nidus (Linnaeus) Smith in Hook. 1842 B06, Thamnopteris nidus (Linnaeus) Presl 1849 I88]

Asplenium obliquissimum (Hayata) Sugimoto & Kurata 1959 [incl. A. unilaterale var. udum Atkin. ex Bedd. 1883] I88

Asplenium yoshinagae Makino 1900 YM03, I88 [incl. A. indicum Sledge 1965 I88, A. planicaule Wallich ex Mett. 1859 non Lowe 1858 I88, A. laciniatum var. planicaule (Wallich) Bedd. 1883 I88]

*Type species of generic name indicated

REFERENCES

[A27] Andersen, J. C. 1927. Popular names of New Zealand plants. Transactions and Proceedings of the New Zealand Institute 57: 905-977.

[B06] Biswas, A. 2006. Pteridophytes of Indian Botanic Garden, Howrah. Bulletin of the Botanical Survey of India 48 (1-4): 175-188.

[C45] Colenso, W. 1845. Memoranda of an excursion, made in the Northern Island of New Zealand, in the summer of 1841-2; intended as a contribution towards the natural productions of the New Zealand groupe: with particular reference to their botany (concluded). Tasmanian Journal of Natural Science 2: 241-308.

[C49] Crookes, M. W. 1949. A revised and annotated list of New Zealand Filicinae. Transactions and Proceedings of the Royal Society of New Zealand 77 (2): 209-225.

[D03] Dusén, P. 1903. The vegetation of western Patagonia. In Reports of the Princeton University Expeditions to Patagonia, 1896-1899, vol. 8 – Botany (W. B. Scott, ed.) pp. 1-34. The University: Princeton (New Jersey).

[G60] Gillham, M. E. 1960. Vegetation of Little Brother Island, Cook Strait, in relation to spray-bearing winds, soil salinity, and pH. Transactions of the Royal Society of New Zealand 88 (3): 405-424.

[I88] Iwatsuki, K. 1988. An enumeration of the pteridophytes of Nepal. In The Himalayan Plants vol. 1 (H. Ohba & S. B. Malla, eds) The University Museum, University of Tokyo, Bulletin 31: 231-339.

[J87] Judd, W. S. 1987. Floristic study of Morne La Visite and Pic Macaya National Parks, Haiti. Bulletin of the Florida State Museum – Biological Sciences 32 (1): 1-136.

Kramer, K. U., & R. Viane. 1990. Aspleniaceae. In: Kramer, K. U., & P. S. Green (eds) The Families and Genera of Vascular Plants vol. 1. Pteridophytes and Gymnosperms pp. 52-57. Springer.

[L54] Lötschert, W. 1954. Beitrag zur Pteridophyten-Flora von Mittel-Amerika. Senckenbergiana Biologica 35 (1-2): 109-119.

[M03] Macloskie, G. 1903. Pteridophyta, ferns and fernlike plants. In Reports of the Princeton University Expeditions to Patagonia, 1896-1899, vol. 8 – Botany (W. B. Scott, ed.) pp. 127-138. The University: Princeton (New Jersey).

[M06] McCaw, W. L. 2006. Asplenium aethiopicum recolonises karri forest following timber harvesting and burning. Journal of the Royal Society of Western Australia 89 (3): 119-122.

[PT98] Panitsa, M., & D. Tzanoudakis. 1998. Contribution to the study of the Greek flora: Flora and vegetation of the E Aegean islands Agathonisi and Pharmakonisi. Willdenowia 28: 95-116.

[PB04] Perrie, L. R., & P. J. Brownsey. 2004. trnL intron variation in New Zealand taxa of the Asplenium obtusatum chloroplast group. Tuhinga 15: 1-5.

[SS04] Schneider, H., E. Schuettpelz, K. M. Pryer, R. Cranfill, S. Magallón & R. Lupia. 2004. Ferns diversified in the shadow of angiosperms. Nature 428: 553-557.

[SL05] Small, R. L., E. B. Lickey, J. Shaw & W. D. Hauk. 2005. Amplification of noncoding chloroplast DNA for phylogenetic studies in lycophytes and monilophytes with a comparative example of relative phylogenetic utility from Ophioglossaceae. Molecular Phylogenetics and Evolution 36: 509-522.

[S89] Squinabol, S. 1889. Res Ligusticae. VII. – Cenno preliminare sulla flora fossile di Santa Giustina. Annali del Museo Civico di Storia Naturale di Genova, Serie 2a 7: 73-76.

[YM03] Yatabe, Y., & N. Murakami. 2003. Recognition of cryptic species in the Asplenium nidus complex using molecular data – a progress report. Telopea 10 (1): 487-496.