Bartsia is a genus of flowering plants in the family Orobanchaceae, belonging to the tribe Rhinantheae. The genus was described by Carl Linnaeus and currently encompasses a small number of accepted species following recent taxonomic revisions that resolved its polyphyletic nature.
In a 1990 revision, Bartsia was circumscribed to include 49 species, 45 of which are endemic to the Andes of South America. The most widely known member is Bartsia alpina (velvetbells), a semi-parasitic perennial herb with a circumboreal distribution spanning the mountainous and arctic regions of the Northern Hemisphere. Two additional afromontane species, Bartsia decurva and Bartsia longiflora, are restricted to the highlands of northeastern Africa.
Because these three geographic groups — Andean, afromontane, and circumboreal — represent distinct evolutionary lineages, the genus in its broad sense is polyphyletic. To address this, taxonomists have proposed transferring all South American species to the new genus Neobartsia (coined to preserve traceability with Bartsia while signalling its New World affinity), and reclassifying the two African species into the existing genus Hedbergia. Under the strict sense (sensu stricto), Bartsia is the sister genus to Odontites, Bellardia, Tozzia, Hedbergia, and Euphrasia within core Rhinantheae.
Like other members of Orobanchaceae, Bartsia species are hemiparasitic — capable of photosynthesis but also obtaining water and nutrients by attaching to the roots of host plants.
Etymology
The genus Bartsia was named by Carl Linnaeus in honour of his associate Johann Bartsch (Latinized as Johannes Bartsius, 1709–1738), a botanist from Königsberg. The spelling Bartschia has occasionally appeared as an alternative. Curiously, Starbia — an anagram of Bartsia — is another genus within Orobanchaceae, now treated as a synonym of Alectra.
Distribution
Bartsia alpina has a circumboreal distribution, occurring across arctic and subalpine zones throughout the Northern Hemisphere. Two afromontane species are confined to mountain ranges of northeastern Africa, while the bulk of the genus's historical species diversity (45 of 49 species in the 1990 revision) is centred in the Andes of South America — though most of these are now proposed for transfer to the segregate genus Neobartsia.
Taxonomy Notes
Bartsia belongs to the tribe Rhinantheae within Orobanchaceae, forming part of the core Rhinantheae clade and sister to Odontites, Bellardia, Tozzia, Hedbergia, and Euphrasia. Molecular phylogenetic analyses have demonstrated that the genus as historically circumscribed is polyphyletic: its Andean, afromontane, and circumboreal members belong to separate lineages. Two proposed solutions would transfer the South American species to Neobartsia and the two African species to Hedbergia, leaving Bartsia sensu stricto represented principally by B. alpina in Europe. GBIF places the genus in family Scrophulariaceae/order Scrophulariales, reflecting an older classification that pre-dates the broad Orobanchaceae circumscription now standard in APG treatments.
