▪ fern family
 only family in the fern order Ophioglossales, a primitive group of ferns. The family contains four genera and about 80 species. Its members are characterized by leaves (fronds) that are divided into two parts, a sterile green blade and a fertile spike with spore-producing structures (sporangia) embedded in its tissues. Most species produce only one such frond each season. The separate genera are distinguished mainly by the position and structure of the sporangia.

      The genus Ophioglossum (adder's-tongue ferns), with 25–30 tropical and temperate species, has sporangia in two rows near the tip of a usually unbranched, narrow, fertile spike. The genus Botrychium, with about 50 species, distributed throughout the world, includes the grape ferns, moonworts, and rattlesnake fern; some of these species have been placed into segregate genera by various authorities. Helminthostachys, with one species (H. zeylanica) in Sri Lanka and regions extending from the Himalayas to Queensland, Australia, has sporangia in small groups on both sides of the fertile spike.

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Universalium. 2010.

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  • Ophioglossaceae — prop. n. A natural family of succulent ferns cosmopolitan in distribution. Syn: family {Ophioglossaceae}. [WordNet 1.5] …   The Collaborative International Dictionary of English

  • Ophioglossaceae —   [griechisch], die Natternzungenfarne …   Universal-Lexikon

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  • Ophioglossaceae — Natternzungengewächse Echte Mondraute (Botrychium lunaria; rechts) und Gewöhnliche Natternzunge (Ophioglossum vulgatum) Systematik …   Deutsch Wikipedia

  • Ophioglossaceae — noun a family of succulent ferns of order Ophioglossales; cosmopolitan in distribution • Syn: ↑family Ophioglossaceae • Hypernyms: ↑fern family • Member Holonyms: ↑Ophioglossales, ↑order Ophioglossales …   Useful english dictionary

  • Ophioglossaceae — Сем. Ужовниковые 9. Ophioglossum L. – Ужовник 10. Botrychium Sw. – Гроздовник …   Флора Центрально-лесного государственного заповедника

  • ophioglossaceae — ophio·glos·sa·ce·ae …   English syllables

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