Metaxya
| Metaxya | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name of the family | ||||||||||||
| Metaxyaceae | ||||||||||||
| Pic.Serm. | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Metaxya | ||||||||||||
| C. Presl |
Metaxya is a genus of ferns and the only genus inthe Metaxyaceae family . The family belongs to the tree ferns (Cyatheales)according to their relational position,but their members do not form a tribe.
description
The rhizome is short creeping to ascending and dorsiventral. It has a Solenostele with multicellular hair on the tip. The petiole has a wavy vascular bundle omega-shaped in cross section . The leaf blades are simply pinnate. The nerves end freely, are simple or forked at the base and then roughly parallel.
The sori are on the underside of the leaf, are round and arranged in some indistinct rows, often several sori are on one nerve. Indusia are absent. The sporangia ripen at the same time. The Sporangienstiel is four rows. The annulus is horizontal and slightly opaque. 64 spores are formed per sporangium, these are spherical and trilet (three-part scar).
The basic chromosome number is x = 95 or 96.
Occurrence
The genus occurs in the Neotropic , its species grow terrestrially . Type species is Metaxya rostrata .
literature
- Alan R. Smith, Kathleen M. Pryer, Eric Schuettpelz, Petra Korall, Harald Schneider, Paul G. Wolf: A classification for extant ferns. In: Taxon. Volume 55, No. 3, 2006, ISSN 0040-0262 , pp. 705-731, abstract, PDF file .
