Polypodium

Polypodium microrhizoma, photographed by Ralf Knapp.

Belongs within: Pteridales.

Polypodium is a cosmopolitan genus of ferns, particularly diverse in the American tropics. Species of this genus possess a creeping rhizome from which fronds are borne. The circumscription of this genus has been subject to some dispute; it is now treated more narrowly than it has been in the past, and some authors would further subdivide it.

Characters (from Hennipman et al. 1990): Epiphytic, epilithic, or terrestrial, small to large ferns; stem rather short to long-creeping, sometimes bearing a wax-like bloom, clothed with usually peltate or pseudopeltate, rarely basifixed, opaque, clathrate or centrally clathrate, entire to toothed scales, their margin usually bearing 1- or 2-celled, unbranched, glandular appendages. Leaves usually remote, articulate at base, monomorphic to dimorphic. Monomorphic and sterile leaves with short to long, scaly or glabrous petiole; lamina simple, pinnatifid, pinnatisect, or l-pinnate, rarely up to bipinnate + pinnatifid, most often deeply, pectinately pinnatifid to pinnate, truncate or narrowed at base, herbaceous to coriaceous, glabrous, pubescent, or variously scaly; veins free or anastomosing; venation simple to complex, usually with one row of areokes with one excurrent free vein, sometimes several rows of areoles with free, simple or forked veins that are usually excurrent or sometimes pointing to all sides. Fertile leaves conform to sterile ones or larger and/or narrower. Sori usually in one, sometimes more rows on either side of the primary or secondary veins, terminal or compital, usually rounded, rarely elongate or linear; sporangia long-stalked, annulus with about 12-20 indurated cells; receptacular hairs and/or scales of one form or another usually present. Spores hyaline to yellow, ellipsoidal, ends often obtuse; surface coarsely verrucate or low-verrucose, tuberculate, or papillate with dense globules, or with prominent wings; exospore of two layers, the outer verrucate or tuberculate; perispore thin, conforming to exospore, or in some species forming prominent folds; n=37, 74; 2n=74, 111, 148.

Polypodium
    |  i. s.: P. angustifolium L54
    |         P. antillense J87
    |         P. appalachianum SL05
    |         P. astroplepis L54
    |         P. aureum J87
    |         P. cambricum PT98
    |         P. delitescens L54
    |         P. dissimile J87
    |         P. glycyrrhiza PS01
    |         P. heteromorphum L54
    |         P. induens L54
    |         P. lanceolatum L54
    |           |--P. l. var. lanceolatum L54
    |           `--P. l. var. trichophorum L54
    |         P. lasiopus J87
    |         P. loriceum J87
    |         P. montigenum L54
    |         P. novae-zelandiae A27
    |         P. pectinatum J87
    |         P. polypodioides J87
    |         P. simplex P03
    |         P. squamatum J87
    |         P. sylvaticum C45
    |         P. thysanolepis J87
    |         P. triseriale L54
    |         P. vulgare Linnaeus 1753 CD07
    |--P. subg. Polypodium I88
    |    |--P. amoenum Wallich ex Mett. 1857 (see below for synonymy) I88
    |    |--P. atkinsonii Christensen 1906 (see below for synonymy) I88
    |    |--P. lachnopus Wallich ex Hooker 1863 [=Goniophlebium lachnopus (Wallich) Bedd. 1883] I88
    |    |--P. microrhizoma Clarke ex Baker in Hooker & Baker 1874 (see below for synonymy) I88
    |    `--P. subamoenum Clarke 1880 [=Goniophlebium subamoenum (Clarke) Bedd. 1883] I88
    `--P. (subg. Goniophlebium) argutum Wallich ex Hooker 1863 [=Goniophlebium argutum (Wallich) Bedd. 1865] I88

Nomina nuda: Polypodium isseli Squinabol 1889 S89
             Polypodium viscidum Colenso 1845 C45

Polypodium amoenum Wallich ex Mett. 1857 [=Goniophlebium amoenum (Wallich) Bedd. 1865; incl. P. amoenum f. pilosum Clarke 1880] I88

Polypodium atkinsonii Christensen 1906 [=P. hendersonii Atkins. apud Baker in Hooker 1874 non Lowe 1858, Goniophlebium hendersonii Bedd. 1876] I88

Polypodium microrhizoma Clarke ex Baker in Hooker & Baker 1874 [=Goniophlebium microrhizoma (Clarke) Bedd. 1876] 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.

[CD07] Cantino, P. D., J. A. Doyle, S. W. Graham, W. S. Judd, R. G. Olmstead, D. E. Soltis, P. S. Soltis & M. J. Donoghue. 2007. Towards a phylogenetic nomenclature of Tracheophyta. Taxon 56 (3): E1-E44.

[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.

Hennipman, E., P. Veldhoen, K. U. Kramer & M. G. Price. 1990. Polypodiaceae. In: Kramer, K. U., & P. S. Green (eds) The Families and Genera of Vascular Plants vol. 1. Pteridophytes and Gymnosperms pp. 203-230. Springer.

[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.

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

[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.

[P03] Paul, T. K. 2003. Botanical observations on the Purulia pumped storage hydropower project area, Bagmundi Hills, Purulia district, West Bengal. Bulletin of the Botanical Survey of India 45 (1-4): 121-142.

[PS01] Pryer, K. M., A. R. Smith, J. S. Hunt & J. Y. Dubuisson. 2001. rbcL data reveal two monophyletic groups of filmy ferns (Filicopsida: Hymenophyllaceae). American Journal of Botany 88 (6): 1118-1130.

[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.