Chromosome numbers are reported for 50 collections of Malvaceae from Argentina, Bolivia,
Brasil, Chile, Mexico and Paraguay representing 17 genera and 40 species. First chromosome
counts are reported for the following 28 species: Cienfuegosia conciliata 2n=20, Hibiscus
striatus 2n=52, H. adscensionis 2n=72, Phragmocarpidium Heringeri 2n=50, Malachra radiata
2n=56, Pavonia Friesii 2n=56, P. fruticosa 2n=56, P. subrotunda 2n=56, Monteiroa Reitzii
2n=20, Tarasa nototrichoides 2n=10, Tropidococcus pinnatipartitus 2n=24, Chstaria disssecta
2n=12, Gaya Bordasii 2n=12, Pseudabutilon cinereum 2n=16, Abutilon fluviatile 2n=16, A.
laxum 2n=16, Wissadula Fadyenii 2n=14, Sida vespertina 2n=14, S. Glaziovii 2n=28, S.
glomerata 2n=14, S. hirsutissima 2n=28, S. planicaulis 2n=28, S. Rodrigoi 2n=28, S. ulmifolia
2n=28, S. Hatschbachii 2n=42, S. Reitzii 2n=42, S. aggregata 2n=16, S. rufescens 2n=32