Gleicheniaceae

Gleicheniaceae

▪ plant family
      the forking fern family, containing 6 genera and about 125 species, in the division Pteridophyta (the lower vascular plants (plant)). This relatively primitive family has a long fossil history dating back to the Jurassic Period (about 200 to 150 million years ago). The extant genera are Gleichenella (1 species), Strematopteris (1 species), Dicranopteris (12 species), Diplopterigyium (25 species), Gleichenia (10 species), and Sticherus (about 80 species). The group is most diverse in the Paleotropics but is also well represented in warmer regions of the New World. Many of the species are colonizers of open or disturbed areas and are commonly seen along road banks in the tropics.

      The leaves of most Gleicheniaceae are atypical for ferns in that they have a peculiar pattern of development. The rachis (main axis) of the lamina forks at all or most nodes, with a “dormant bud” between the branches that appears as a short fiddlehead. This indeterminate pattern of leaf growth and branching results in extremely long leaves that creep and climb over the ground and other vegetation, forming large masses of overlapping leaves. The sporangia (fern) are clustered into small round naked sori (fern) along the secondary veins. Both bean-shaped (bilateral) and globose (terahedral) spores occur in the family.

George Yatskievych
 

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Universalium. 2010.

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Look at other dictionaries:

  • Gleicheniaceae — ? Gleicheniaceae Clasificación científica …   Wikipedia Español

  • Gleicheniacĕae — Gleicheniacĕae, Familie der Klasse der Farnkräuter, Keimbehälter (Sporangien) auf dem Rücken der Wedel, stiellos, mit einem breiten, vollständigen, der Quere nach od. etwas schräg laufenden Ringe, nach Innen der Quere nach aufspringend;… …   Pierer's Universal-Lexikon

  • Gleicheniaceae — Gleicheniaceae, Farrenkräuter mir gefiedertem Wedel, meist gabelig verästelt, mit stiellosen Keimbehältern auf dem Rücken der Wedel, länglichen oder nierenförmigen Keimkörnern …   Herders Conversations-Lexikon

  • Gleicheniaceae — Forked ferns Diplopterygium pinnatum of the Gleichenioideae Scientific classification Kingdom: Pl …   Wikipedia

  • Gleicheniaceae — noun a family of ferns belonging to order Filicales • Syn: ↑family Gleicheniaceae • Hypernyms: ↑fern family • Member Holonyms: ↑Filicales, ↑order Filicales, ↑Polypodiales, ↑ …   Useful english dictionary

  • Семейство глейхениевые (Gleicheniaceae) —         Около 160 видов глейхениевых распространены во влажных, нередко горных районах тропиков и субтропиков, а также в умеренных широтах южного полушария. Северная граница их распространения проходит через Японию в восточном полушарии и Мексику …   Биологическая энциклопедия

  • family Gleicheniaceae — noun a family of ferns belonging to order Filicales • Syn: ↑Gleicheniaceae • Hypernyms: ↑fern family • Member Holonyms: ↑Filicales, ↑order Filicales, ↑Polypodiales, ↑order …   Useful english dictionary

  • fern — fernless, adj. fernlike, adj. /ferrn/, n. any seedless, nonflowering vascular plant of the class Filicinae, of tropical to temperate regions, characterized by true roots produced from a rhizome, triangular fronds that uncoil upward and have a… …   Universalium

  • Fern — /ferrn/, n. a female given name. * * * Any of about 10,000–12,000 species (division Filicophyta) of nonflowering vascular plants that have true roots, stems, and complex leaves and reproduce by spores. Though ferns were once classified with the… …   Universalium

  • Роды сосудистых споровых — Приложение к статье Сосудистые споровые …   Википедия

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