Unraveling the taxonomic identity of Cocos nucifera f. palmyrensis (Arecaceae: Cocoseae)

The main traits of the rich equatorial vegetation covering the remote coral atoll Palmyra in North Pacific Ocean, where groves of Cocos nucifera L. (Arecaceae) currently dominate on other formations, are here summoned. Way and timing of human activities in historical and more recent times, which possibly altered the original vegetation, are also briefly reviewed. The unusually large size of Palmyra coconut fruits had astonished the American botanist Joseph Francis Rock (1884 – 1962) who sent four fruits to the renowned Florentine palm specialist Odoardo Beccari (1843 – 1920). Beccari described the material and validly published it in 1916 as Cocos nucifera f. palmyrensis Becc. Part of the original material was retrieved at FI. One of the two coconut fruits still kept at FI is here designated as lectotype of the Beccari name, which is here elevated to the rank of variety, reflecting better than form current concepts for isolated island populations. Palmyra Atoll with its coconuts played a part in the age-old dispute on the geographical origin of Cocos nucifera. This taxon was cited by Beccari and by Emilio Chiovenda (1871 – 1941) as a support to their hypotheses of an Asian origin of the species. The significance of these dated interpretations in the light of currently available information is here briefly discussed.