Ophioglossum costatum

Description

Ophioglossum, the adder's-tongue ferns, is a genus of about 25�30 species of ferns in the family Ophioglossaceae, of the order Ophioglossales. The name Ophioglossum comes from the Greek and means snake-tongue.Their cosmopolitan distribution is mainly in tropical and subtropical habitats.Adders-tongues are so-called because the spore-bearing stalk is thought to resemble a snake's tongue. Each plant typically sends up a small, undivided leaf blade with netted venation, and the spore stalk forks from the leaf stalk, terminating in sporangia which are partially concealed within a structure with slitted sides.When the leaf blade is present, there is not always a spore stalk present, and the plants do not always send up a leaf, sometimes going for a year to a period of years living only under the soil, nourished by association with soil fungi.The plant grows from a central, budding, fleshy structure with fleshy, radiating roots.