Abstract
The order Malpighiales, which comprises 39-40 families of flowering plants, are poorly understood in terms of their morphological characters and the relationships among the families. Here, we present the first chromosome counts of Irvingiaceae, Ixonanthaceae, Lacistemataceae, and Peraceae, based on one or two species each, using somatic cells from young leaves. The chromosome numbers were 2n=30 for Irvingia malayana (Irvingiaceae), 2n=28 for Ixonanthes icosandra and I. reticulata (Ixonanthaceae), 2n=44 for Lacistema aggregatum (Lacistemataceae), and 2n=36 for Chaetocarpus castanocarpus (Peraceae). The relationships of individual families based on chromosome numbers are discussed briefly.
