4. Commelina obliqua Vahl (S-Am.) – An exceptional and ephemeral soybean alien, recorded in 1999 and 2000 in the port of Gent.
This species is, even in non-flowering plants, easily distinguished from Commelina communis in being much more hairy (stem, leaf sheaths). It a widespread weed of agricultural fields in subtropical South America and possibly overlooked as an alien in Europe.