The Ophioglossaceae possess a suite of characters that long ago prompted speculation on their possible descent from Paleozoic Coenopterid ferns. The combination of vascular cambium (Botrychium), collateral vascular bundles, non-circinnate vernation, single annual leaf cleft into fertile and sterile segments, underground apex with preformed leaves, simple, fleshy, hairless mycorrhizal roots and long-lived subterranean gametophytes suggest a lineage separate from the remainder of ferns. Many of these plants possess remarkably low intraspecific genetic diversity, perhaps due to underground fertilization, and perhaps allowed by their mycorrhizal relationship. Despite low genetic variability, Botrychium species appear to have undergone recent and continuing speciation. Aspects of Ophioglossaceae morphology, phytogeography, speciation, and systematic relationships will be presented in the first half of the symposium. Ecology and conservation issues will be presented in the second half. Subtle species differences in morphology, combined with small size, irregular appearance above ground, and rarity of many of the species, present daunting challenges in conservation management. Spore germination, gametophyte growth, fertilization and juvenile sporophyte stages occur below ground. Current analyses of critical underground stages are increasing our understanding of population dynamics in Botrychium. Reviews of Ophioglossaceae floristics and conservation needs in North America conclude the symposium.

Key words: Botrychium, conservation biology, Ophioglossaceae, Ophioglossum