Trachymene is a genus of herbaceous flowering plants in the family Araliaceae, order Apiales. The genus comprises roughly 40–50 species of annuals and perennials bearing the characteristic compound umbels of the carrot family, with small five-petalled flowers arranged in flat-topped or rounded heads. Leaves are typically divided or deeply lobed, and stems are often slender and erect. The genus has historically been placed in Apiaceae and some sources continue to use that treatment; current molecular phylogenies support its inclusion in the broadly circumscribed Araliaceae.
The centre of diversity lies in Australia, where the great majority of species occur across a range of habitats from coastal scrub to arid interior regions. Additional species extend into Malesia (the Malay Archipelago and New Guinea), New Caledonia, and Fiji. The best-known member is Trachymene coerulea (blue lace flower), an Australian annual widely grown as a garden ornamental for its delicate lavender-blue umbels. Other species carry vernacular names such as wild parsnip, native parsnip, and purple parsnip, reflecting their superficial resemblance to relatives in the carrot tribe.
Distribution
Trachymene is centred in Australia, where most species occur across habitats ranging from the coast to the arid interior. The genus also extends into Malesia, New Caledonia, and Fiji.
Taxonomy Notes
Trachymene has historically been placed in Apiaceae (carrot family) and some taxonomic treatments retain that placement; molecular work supports its current position in the broadly circumscribed Araliaceae, order Apiales. GBIF lists Trachymene under Apiaceae as a synonym in one checklist while accepting it in Araliaceae in others.
