Ophioglossum vulgatum

Ophioglossum vulgatum, commonly known as adder's-tongue, southern adders-tongue or adders-tongue fern, is a species of fern in the family Ophioglossaceae. It is native to many regions with a wide scattered distribution: throughout temperate through tropical Africa; and throughout the temperate Northern Hemisphere in Europe, northeastern North America, temperate Asia, and Eurasia. This small, hard-to-spot plant can occur singly in unimproved pastures, rock crevices and grassy path-sides, but also can occur in colonies of hundreds of plants in sand dunes. Ophioglossum vulgatum grows from a rhizome base to 10–20 cm tall (rarely to 30 cm). It consists of a two-part frond, separated into a rounded diamond-shaped sheath and narrow spore-bearing spike. The spike has around 10-40 segments on each side.