North America Non-native Plant

Thelypteris Asterothrix

Botanical name: Thelypteris asterothrix

USDA symbol: THAS3

Native status: Not native but doesn't reproduce and persist in the wild

The Mystery of Thelypteris asterothrix: A Rare and Elusive Fern If you’ve stumbled upon the name Thelypteris asterothrix in your plant research, you’ve encountered one of botany’s more mysterious characters. This fern species sits firmly in the hard to find information about category, making it something of an enigma for ...

The Mystery of Thelypteris asterothrix: A Rare and Elusive Fern

If you’ve stumbled upon the name Thelypteris asterothrix in your plant research, you’ve encountered one of botany’s more mysterious characters. This fern species sits firmly in the hard to find information about category, making it something of an enigma for both gardeners and botanists alike.

What We Know (And Don’t Know)

Thelypteris asterothrix belongs to the Thelypteris genus, commonly known as marsh ferns or maiden ferns. However, unlike its well-documented cousins in the fern family, this particular species remains shrouded in uncertainty. The lack of readily available information about T. asterothrix could mean several things:

  • It might be an extremely rare species with limited distribution
  • The name could be a synonym for another, better-known fern
  • There may be ongoing taxonomic research that hasn’t yet been widely published
  • It could be a regional name not widely recognized in standard botanical literature

The Thelypteris Family Connection

While we can’t say much specifically about T. asterothrix, we do know it belongs to a fascinating group of ferns. The Thelypteris genus includes species that are typically medium-sized, deciduous ferns with delicate, lacy fronds. Many members of this family are moisture-lovers, often found in wetland areas, along stream banks, or in consistently damp woodland settings.

Why the Mystery Matters

The scarcity of information about Thelypteris asterothrix actually tells us something important about plant diversity and conservation. There are countless plant species around the world that remain poorly studied or documented. Some exist in remote locations, others have very small populations, and some simply haven’t received the scientific attention they deserve.

For the Curious Gardener

If you’re interested in this particular fern, here’s what we recommend:

  • Contact local botanical gardens or native plant societies for more information
  • Reach out to fern specialists or pteridologists who might have knowledge of rare species
  • Consider exploring other well-documented Thelypteris species that might be available for cultivation
  • If you believe you’ve encountered this fern in the wild, document it with photos and location data for researchers

Alternative Fern Options

While we wait for more information about T. asterothrix to emerge, there are plenty of other beautiful Thelypteris species and related ferns that make excellent garden additions. Look for well-documented species like the New York fern (Thelypteris noveboracensis) or broad beech fern (Thelypteris hexagonoptera) if you’re drawn to this family of plants.

The plant world still holds many secrets, and Thelypteris asterothrix appears to be one of them. Sometimes the most intriguing plants are the ones that keep us guessing!

Thelypteris Asterothrix

Classification

Group

Fern

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision
Division

Pteridophyta - Ferns

Subdivision
Class

Filicopsida

Subclass
Order

Polypodiales

Family

Thelypteridaceae Ching ex Pic. Serm. - Marsh Fern family

Genus

Thelypteris Schmidel - maiden fern

Species

Thelypteris asterothrix (Fée) Proctor [excluded]

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