Five decades of research on the Antarctic vascular plant Colobanthus quitensis (Caryophyllaceae)

Colobanthus quitensis is the only native dicotyledonous vascular plant in Antarctica and a valuable system for examining plant persistence near the climatic limits of terrestrial life. We critically synthesize 150 species-level records (148 published papers and two preprints) spanning taxonomy, biogeography, reproductive and seed biology, ecophysiology, metabolism, plant–microbe interactions, genomics, epigenetics, and biotechnology. Broadly sampled phylogeographic and molecular dating analyses favour multiple Late Pleistocene colonizations of Maritime Antarctica from southern South America, possibly after initial post-glacial ice retreat, rather than survival as a Tertiary Antarctic relict; however, the number and location of dispersal or refugial events remain unresolved. Persistence is supported by autonomous self-pollination, persistent seed banks, microhabitat filtering, positive carbon gain near freezing, cold acclimation, flavonoid-based UV-B screening, and context-dependent microbial effects on nutrition and stress tolerance. Warming can increase growth, photosynthesis, and reproductive performance, but may also reduce freezing resistance, intensify drought and freeze–thaw stress, and alter competition. Recent genomic, transcriptomic, epigenetic, and metatranscriptomic resources now permit stronger links between molecular responses and field performance. We conclude that C. quitensis exhibits conditional, multilevel resilience rather than a single Antarctic adaptation, and identify priorities for predictive, population-aware research under rapid environmental change.