The distribution of Podostermaceae in Ghana

Abstract

The distribution of five species of Podostemaceae, namely, Ledermanniella bowlingii, Polypleurum submersum, Saxicolella agumatsa, Saxicolella amicorum and Tristicha trifaria occurring in Ghana has been described. T. trifaria is widespread in the country. The other Podostemaceae species are at present known from one, two or three rivers. S. agumatsa was found on the cliff surface of the Wli falls on the Agumatsa river. L. bowlingii and P. submersum were found in two rivers, namely, Asuboni river, near Kwahu Nteso and Akrum river, near Begoro. S. amicorum occurred in three rivers in different geographical areas: in Ankasa river in the Ankasa Resource Reserve, in the Kakum river near Asuansi and in Nwhini river, near Aduabrim. All the five species occurred in the wet semi-equatorial climate type. T. trifaria is known from the dry equatorial and tropical continental climate types. S. amicorum and T. trifaria were found in the semi-equatorial climate type. T. trifaria occurs in both low and high rainfall areas, from areas with less than 1000 mm to areas above 1900 mm of rainfall y-1. The other species are confined to higher annual rainfall areas of 1250 to above 1900 mm. In Ghana Podostemaceae were found to occur on older rocks of the Precambrian and Palaeozoic eras, and not on rocks of recent origin. They occur between 75–900 m above sea level.

JOURNAL OF THE GHANA SCIENCE ASSOCIATION Volume 2 No. 1 (2000) pp. 31-38