Cardiospermum L.
Cardiospermum is a genus with seventeen species (Gildenhuys & al. 2013) that are nearly all confined to the New World (with one species extending to Africa). The center of diversity of the genus obviously is in Brazil (Ferrucci & Umdiriri 2011). At least two species are economically important: C. halicacabum L. is an aggressive weed of agricultural fields, whereas C. grandiflorum Sw. – often grown as an ornamental vine – has become a noxious environmental weed in warm-temperate and subtropical areas across the world. Both have been recorded in Belgium, although the record of the latter as a wool alien in 1959 (Verloove 2006) is highly questionable. It is therefore not included in the present account.
References
Ferrucci M.S. & Umdiriri J.D. (2011) Cardiospermum bahianum (Sapindaceae: Paullinieae), a new species from Bahia, Brazil. Systematic Botany 34: 950-956.
Gildenhuys E. (2013) Unravelling taxonomic uncertainties among balloon vine species within the genus Cardiospermum using a molecular approach. PhD Thesis, Stellenbosch University: 126 p. [available online at: http://scholar.sun.ac.za]
Gildenhuys E., Ellis A.G., Carroll S.P. & Le Roux J.J. (2013) The ecology, biogeography, history and future of two globally important weeds: Cardiospermum halicacabum Linn. and C. grandiflorum Sw. NeoBiota 19: 45-65. [available online at: https://doi.org/10.3897/neobiota.19.5279]
Gildenhuys E., Ellis A.G., Carroll S.P. & Le Roux J.J. (2015) Combining natal range distributions and phylogeny to resolve biogeographic uncertainties in balloon vines (Cardiospermum, Sapindaceae). Diversity Distrib. 21: 163-174.
Verloove F. (2006) Catalogue of neophytes in Belgium (1800-2005). Scripta Botanica Belgica 39: 89 p. [available online at: http://alienplantsbelgium.be/sites/alienplantsbelgium.be/files/tabel_2.pdf]