Morphometrics of herbaceous bamboos of the Raddia brasiliensis complex (Poaceae − Bambusoideae): implications for the taxonomy of the genus and new species from Brazil

Abstract

Morphometric studies were conducted using 25 quantitative characters in 14 populations of the Raddia brasiliensis complex, occurring from Ceara to Rio de Janeiro States, Brazil, in order to identify how many entities exist in this group and how they can be distinguished morphologically. Results of the discriminant and cluster analyses show that we are dealing with five distinct taxa, four of them here described as new species. A group of populations from northern Espirito Santo and southern Bahia showed high differentiation in relation to other areas. They are here considered as the new species R. megaphylla. Two other distinct populations also showed significant differentiation, described as R. lancifolia and R. stolonifera. Raddia brasiliensis s.s. turned out to be polymorphic and closely related to another new species, R. soderstromii. They present some ecological preferences related to soil and water conditions. These conclusions were supported by genetic data based on allozymes analysis.