Spiral thickenings in the axial parenchyma of Chrysobalanaceae

Spiral thickenings in the axial parenchyma, seldom recorded in the secondary xylem of the dicotyledons so far, are described for a number of genera and/or species of Chrysobalanaceae. In 66 out of 99 samples investigated, representing most genera of the Chrysobalanaceae, spiral thickenings proved to be present. Some genera, such as Parinari, like Chrysobalanus, lack spirals while others Exellodendron and Hirtella comprise only species with spiral thickenings. In Acioa, Couepia, Cyclandrophora, Licania and Maranthes only a part of the species have spirals in their parenchyma cells. Data on distribution and appearance are given. No connection with tension wood could be demonstrated, neither is the presence related to juvenile wood. Taxonomic value of the spirals in the axial parenchyma is discussed.