Mononeuria is a genus of small flowering plants in the family Caryophyllaceae (the pink family), placed within the order Caryophyllales. The genus comprises roughly ten species of low-growing, mat-forming or tufted annual and perennial herbs, native to subarctic and temperate regions of North America, from Greenland and subarctic Canada south into the eastern and central United States. Plants in the genus are characterised by narrow, linear leaves, wiry stems, and small white five-petalled flowers typical of the Caryophyllaceae. Mononeuria was segregated from the broadly circumscribed genus Minuartia following molecular phylogenetic work by Dillenberger and Kadereit, who demonstrated that the traditional Minuartia as delimited was polyphyletic. The species transferred to Mononeuria had previously been known under Minuartia and, further back, under Arenaria. Several species occupy specialised, often threatened habitats: cedar glades, bog margins, moist sandy substrates, and Arctic-alpine tundra.
Distribution
Mononeuria is native to subarctic America south through the eastern and central United States. Species occur in a range of habitats from Arctic-alpine and subarctic tundra (e.g., M. groenlandica of Greenland and northern North America) to lowland cedar glades, bog margins, and sandy soils of the southeastern and central US (e.g., M. caroliniana, M. patula).
Taxonomy Notes
Mononeuria was established as a segregate genus after molecular studies demonstrated that Minuartia sensu lato, the genus in which these species had long been placed, is polyphyletic. The combination authorities — Dillenberger & Kadereit, and Dillenberger & Rabeler for M. caroliniana — transferred approximately ten North American species to Mononeuria. The genus sits within the family Caryophyllaceae, order Caryophyllales.
