A phenetic study of the genus Monoon Miq. (annonaceae) in Borneo, Indonesia

The number of species within the genus Monoon Miq. (Annonaceae) in Borneo have been studied. This research is aimed to investigate the similarity relationship of the Monoon species in Borneo. The research method was used the Unweighted Pair Group Method with Arithmetic Average (UPGMA) method through the Numerical Taxonomy and Multivariate Analysis (NTSys-pc) program version 2.02. Based on a morphological study from 96 herbarium specimens collected from Borneo the result showed that 23 species of Monoon were obtained. Specimens were observed from 24 characters, including 8 vegetative, 10 inflorescence, and 8 fruit characters. The phenetic tree analysis indicated that the Monoon in Borneo clustered into two major clusters with a coefficient similarity of 0.55, group A and group B. The species with more than 17 pairs of secondary veins clusters in group B which have a higher similarity coefficient than group A. According to the amount of secondary venation. Group A has≤15, while group B has≥17 pairs. Monoon lateriflorum and M. sclerophyllum have the closest relationship in term of morphological characters with similarity index of 0.83.