The stoneworts of Bonaire and Curaçao in 2023

Very little research has been done on the stoneworts (Characeae) of the Caribbean islands. This also applies to the stoneworts of the Dutch Caribbean islands Bonaire and Curaçao (Leeward Antilles). Hitherto, only stoneworts which happened to be collected between 1930 and 1959 during studies of other groups of organisms formed the basis of our knowledge. Eight taxa are known from Bonaire and Curaçao. Early 2023, the first author made a targeted survey for stoneworts on Bonaire and Curaçao. His survey had the great advantage that the rainy season prior to the survey was extremely wet, which resulted in much more fresh water on the surface of the islands than during the wet seasons in previous years. Nevertheless, only three taxa were found: Chara armata, C. leptosperma, and C. zeylanica f. elegans. The latter taxon appeared to be quite common on both islands, sometimes filling entire water bodies, while Chara armata was only found in a single location on Curaçao. Chara leptosperma is new for Bonaire and Curaçao. The cause of the possible decline in the number of stonewort species is not quite clear.