Family: Hypodematiaceae

Origin, Description & Uses:
Didymochlaena truncatula, commonly known as mahogany fern, moon fern, or tree maidenhair, is native to parts of Southeast Asia, including Borneo, Jawa (Java), Sulawesi, and Sumatera (Sumatra). This tropical terrestrial fern grows naturally in moist, shaded forest understories. It is especially valued for its striking new growth, which emerges coppery-red to mahogany before maturing to deep green. With gracefully arching, finely divided fronds and a typical height of 1–4 feet, it is widely cultivated as an ornamental plant for shaded gardens, conservatories, and indoor spaces where humidity and filtered light can be provided.

Risks & Threats:
Although Didymochlaena truncatula is not currently known to be naturalized in Hawai‘i, it reproduces by lightweight wind-dispersed spores and is well adapted to warm, humid, forested environments similar to those found in the islands. These traits—particularly spore dispersal and tolerance of shaded understory conditions—are associated with invasive potential in other fern species introduced to Hawai‘i. As a result, it possesses characteristics that are cause for concern. It is placed in the Evaluate category, meaning further assessment is needed to determine whether it could escape cultivation and negatively impact Hawai‘i’s native ecosystems. Careful monitoring and thoughtful plant selection are recommended.

High Risk Traits:

• Elevation range exceeds 1000 m, demonstrating environmental versatility
  
• Thrives in tropical climates
  
• Shade-tolerant
  
• Spores dispersed by wind and probably water
  
• Prolific spore production
  
• Limited ecological information makes accurate risk prediction difficult

Low Risk Traits:

• No reports of invasiveness or naturalization
  
• Unarmed (no spines, thorns or burrs)
  
• Ornamental
  
• Not reported to spread vegetatively