Family: Acanthaceae

Origin, Description & Uses:
Dianthera pectoralis is native to Mexico through southern tropical America, where it grows in warm, humid environments such as forest edges, clearings, and other disturbed areas. This low-growing, herbaceous member of the acanthus family has soft green foliage and small, tubular flowers that give it some appeal as a groundcover or ornamental in tropical landscapes. In parts of its native range, it has also been used in traditional medicine, although such uses are not well studied and should be approached with caution.

Risks & Threats:
Although Dianthera pectoralis is not currently known to be naturalized in the Hawaiian Islands, it possesses traits that raise concern for potential invasiveness. It can grow quickly, reproduce readily, and establish in disturbed sites—characteristics that often allow plants to spread beyond cultivation. In sensitive island ecosystems like Hawai‘i, introduced species with these traits may outcompete native plants, alter habitats, and disrupt ecological balance. Because of these risks, this species could detrimentally impact tropical island ecosystems if introduced. Choosing a low-risk or native alternative is strongly recommended to help protect Hawai‘i’s unique biodiversity.

High Risk Traits:

• Naturalized outside native range (e.g., Florida)
  
• Weedy in native range (roadsides, waste places)
  
• Shade tolerant
  
• Produces viable seed
  
• Reproduces vegetatively (roots at nodes)
  
• Self-pollinating / no specialist pollinator required
  
• Propagules dispersed unintentionally (high-traffic areas)
  
• Propagules dispersed intentionally by people (medicinal, ornamental)
  
• Tolerates mutilation, cultivation, or fire

Low Risk Traits:

• Not an agricultural, forestry, or environmental weed
  
• No spines, thorns, or burrs
  
• No prolific seed production or persistent seed bank
  
• Limited soil pH range (neutral to mildly alkaline)
  
• No fire hazard
  
• Low animal toxicity in studies