Boykinia is a small genus of flowering plants in the family Saxifragaceae, the saxifrage family, comprising around nine accepted species commonly known as brookfoams. Plants in this genus are glandular, rhizomatous creeping perennials, typically growing in moist, streamside habitats. They are recognised by their highly lobed or toothed leaves and slender inflorescences bearing numerous small, delicate flowers.
The genus has a disjunct distribution, occurring in North America and Japan. In North America, species are found along the west coast from Alaska south to Baja California, as well as in the southeastern United States; in Asia, the genus is represented in Japan (Hokkaido and northern and central Honshu). The type species, Boykinia aconitifolia (Allegheny brookfoam), is native to the Appalachian region of the southeastern United States. Other notable members include Boykinia occidentalis (coastal brookfoam) of the Pacific coast and Boykinia richardsonii (Richardson's brookfoam) of higher latitudes.
Distribution
Boykinia species are native to two widely separated regions: North America, where they occur along the Pacific coast from Alaska to Baja California and in the southeastern United States, and Japan (Hokkaido and northern and central Honshu). The genus is characteristically associated with moist, riparian habitats within these ranges.
Taxonomy Notes
Boykinia belongs to the family Saxifragaceae and is closely related to the saxifrages. GBIF recognises the genus as accepted with approximately 13 descendants. The type species is Boykinia aconitifolia Nutt., described by Thomas Nuttall. Wikipedia currently lists seven accepted species; GBIF records 13 descendants, reflecting infraspecific taxa and synonyms included in the count.
