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Platycerium madagascariensis

Description

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Family Polypodiaceae

Plants perennial , terrestrial , on rock, or often epiphytic, erect , arching , or occasionally pendent. Stems long- to short-creeping, branched or not, bearing scales and few to numerous roots , usually dictyostelic. Leaves monomorphic to dimorphic , circinate in bud. Petiole usually articulate at base [rarely nonarticulate , as in Loxogramme ], lacking scales or sometimes scaly , with usually 3 vascular bundles . Blade simple to often pinnatifid , pinnatisect , or pinnate, infrequently more divided ; rachis grooved or not adaxially. Veins free (and simple to several times forked ) to often anastomosing in complex systems , areoles with or without included veinlets . Indument on blade absent, or petiole, rachis, costae, and sometimes blade tissue usually bearing hairs (these often septate and with reddish crosswalls) and/or scales. Sori borne abaxially on veins, round to oblong , occasionally elongate , rarely marginal , rarely covering surface; paraphyses present or absent; sporangia with stalk of 2 or 3 rows of cells ; indusia absent. Spores usually transparent or yellowish (rarely greenish), all 1 kind, bilateral , monolete [rarely trilete, as in some Loxogramme], surface most often smooth , tuberculate , verrucose , or granulate , occasionally spiny , 64 per sporangium (spores globose and 32 per sporangium in apogamous spp. ) . Gametophytes green, aboveground, cordate or elliptic , glabrous or sometimes glandular ; archegonia and antheridia borne on lower surface, antheridia 3-celled.

Genera ca. 40, species perhaps 500 (7 genera, 25 species in the flora ) : worldwide, especially tropics and subtropics.

Genera in this family are variously circumscribed, and the New World species historically were placed in the single genus Polypodium . Many of the segregates recognized here are still placed in Polypodium in recent floristic accounts. Limits of genera in both Old World and New World are controversial and are currently under study by several workers.[1]

Taxonomy

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Similar Species

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Members of the genus Platycerium

ZipcodeZoo has pages for 12 species, subspecies, varieties, forms, and cultivars in this genus:

P. bifurcatum (Antelope Ears) · P. bifurcatum var. bifurcatum (Common Staghorn Fern) · P. bifurcatum var. Panama (Staghorn Fern) · P. coronarium (Stag's Horn Fern) · P. hillii (Green Staghorn) · P. hillii 'Horn Surprise' (Green Staghorn) · P. holttumii (Holttums Staghorn) · P. ridleyi (Ridleys Staghorn) · P. superbum (Staghorn Fern) · P. veitchii (Silver Elkhorn Fern) · P. wandae (Queen Elkhorn Fern) · P. willinckii (Java Staghorn)

More Info

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Further Reading

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Notes

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Contributors

Identifiers

Footnotes

  1. Alan R. Smith "Polypodiaceae". in Flora of North America Vol. 2. Oxford University Press. Online at EFloras.org. [back]
Last Revised: 2014-04-18