ACHENE MICRO-MORPHOLOGY AS A SYSTEMATIC AID TO THE SERIES PLACEMENT OF SVENSON UNDESIGNATED ELEOCHARIS (CYPERACEAE) SPECIES

Eleocharis species unassigned by Svenson to the series level at the co mpletion of his worldwide monograph were examined utilizing scanning e lectron microscopy. Acid treated achenes with their cuticle and outer periclinal cell walls removed revealed micro-morphological characters in support of assigning E. squamigera and E. subarticulata to the seri es Palustriformes, subseries Truncatae. Although the results failed to delegate unequivocally E. albida and E. melanocarpa, additional insig ht regarding their infrageneric relationship was obtained. An assessme nt of E. minarum proved to be impossible due to the absence of mature achenes.