Adder’s Tongue

Nature Notes

There is more than meets the eye to the adder’s tongue fern (Ophioglossum vulgatum). At first glance you might not guess that it’s even a fern. Lacking the typical delicate-looking leaves of other ferns we’re used to seeing, it has an odd spore-bearing stalk that is unique to its family (the Ophioglossaceae). It is from the shape of this spore-bearing stalk that the plant gets its name, as it was thought to resemble a snake’s tongue. Adder’s tongue also has more chromosomes than any other known organism with a whopping 1,260! Compare that to humans, who only have 46 chromosomes.

Something else that makes adder’s tongue unique is that its gametophyte stage (the stage that produces plant sex cells) is spent entirely underground. As a result, it does not produce food through photosynthesis. Instead, it forms a relationship with soil fungi and receives its nutrients from them. Also, unlike many other seedless plants, its gametophyte stage is long-lived and can persist for years underground living off its fungal hosts.

adders tongue fern

This example of adder’s tongue, which is not of the gametophyte stage, was found in Miami Whitewater Forest. If you keep your eyes open, you might see some adder’s tongue on the Badlands Trail there!

Garrett Dienno, Seasonal Aquatic Resource Technician