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North America Native Plant

Anthoceros Lamellatus

Anthoceros lamellatus: A Critically Rare Hornwort Worth Knowing Ever heard of a hornwort? If you haven’t, you’re not alone! Anthoceros lamellatus is one of North America’s most elusive native hornworts – a fascinating group of ancient plants that most gardeners never encounter. But here’s the thing: this tiny green marvel ...

Rare plant alert!

This plant is listed as rare and may be protected in certain regions. Its populations are limited, and removal from the wild could further endanger its survival. If you wish to enjoy this plant, consider sourcing from reputable nurseries that propagate responsibly or explore alternatives to help preserve natural populations.

Region: Conservation status by state

Status: S1: Status is uncertain but is somewhere between the following rankings: Critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘

Anthoceros lamellatus: A Critically Rare Hornwort Worth Knowing

Ever heard of a hornwort? If you haven’t, you’re not alone! Anthoceros lamellatus is one of North America’s most elusive native hornworts – a fascinating group of ancient plants that most gardeners never encounter. But here’s the thing: this tiny green marvel is critically imperiled, making it one of our continent’s botanical treasures hiding in plain sight.

What Exactly Is a Hornwort?

Hornworts are neither moss nor fern, but something wonderfully unique. Anthoceros lamellatus is a terrestrial green plant that forms small, flat, ribbon-like structures called thalli (think of them as leaf-like bodies without true leaves). What makes hornworts special are their distinctive horn-shaped sporophytes – slender, upright structures that release spores and give these plants their quirky name.

Unlike typical garden plants, hornworts are always herbaceous and often attach themselves to solid surfaces like rocks, fallen logs, or even living tree bark rather than growing directly in soil.

Where Does Anthoceros lamellatus Call Home?

This rare hornwort is native to North America, with most documented populations found in the eastern regions, particularly in the Appalachian area. However, its exact geographical distribution remains somewhat mysterious – partly because it’s so uncommon and partly because hornworts are notoriously difficult to spot unless you know exactly what you’re looking for.

The Rarity Reality Check

Here’s where things get serious: Anthoceros lamellatus has a Global Conservation Status of S1, meaning it’s critically imperiled. With typically five or fewer known occurrences and very few remaining individuals (fewer than 1,000), this little hornwort is fighting for survival. This extreme rarity makes it especially vulnerable to extinction.

Is It Beneficial to Your Garden?

While Anthoceros lamellatus won’t add showy blooms or dramatic foliage to your landscape, hornworts do serve important ecological functions:

  • They help stabilize soil and prevent erosion
  • They indicate clean, unpolluted environments
  • They contribute to biodiversity in woodland ecosystems
  • They provide habitat for tiny soil organisms

However, given its critically imperiled status, this isn’t a plant you should actively seek to introduce to your garden. Instead, if you’re lucky enough to discover it growing naturally on your property, consider yourself a steward of something truly special.

How to Identify Anthoceros lamellatus

Spotting this rare hornwort requires a keen eye and some patience:

  • Look for small, flat, green thalli growing on moist rocks, logs, or soil
  • The plant body appears ribbon-like or strap-shaped
  • During reproductive periods, watch for slender, horn-like structures (sporophytes) emerging from the thalli
  • The entire plant is typically quite small and easily overlooked
  • It prefers shaded, moist locations with good air quality

What If You Find It?

If you suspect you’ve found Anthoceros lamellatus on your property, congratulations – you might be looking at one of North America’s rarest plants! Here’s what to do:

  • Take photographs but don’t disturb the plant
  • Contact your local botanical society or state botanist
  • Consider having the identification confirmed by an expert
  • Protect the area from foot traffic and disturbance
  • Maintain the existing growing conditions

The Bottom Line for Gardeners

Anthoceros lamellatus isn’t a plant you’ll find at your local nursery, nor should it be. This critically rare hornwort is better appreciated as a fascinating example of our continent’s botanical diversity – one that needs our protection more than our cultivation. If you’re interested in supporting native plant diversity, focus on more common native species that can thrive in cultivation while leaving rare treasures like this one to flourish in their remaining natural habitats.

Sometimes the most important thing we can do as gardeners is simply recognize and protect the extraordinary diversity that already exists around us – even when it comes in packages as small and humble as a critically imperiled hornwort.

Anthoceros Lamellatus

Classification

Group

Hornwort

Kingdom

Plantae - Plants

Subkingdom
Superdivision
Division

Anthocerotophyta - Hornworts

Subdivision

Anthocerotae

Class

Anthocerotopsida

Subclass
Order

Anthocerotales

Family

Anthocerotaceae Dumort.

Genus

Anthoceros L. emend. Prosk. - hornwort

Species

Anthoceros lamellatus Steph.

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA