FIGURE 1 in Intraspecific variation of insertion/length of stamens in homostylous flowers of a new species and three other species of Borreria: an unusual case in Rubiaceae

FIGURE 1. Scanning electron microscopy (SEM) micrographs of pollen grains. Borreria heteranthera (A–C from A. J. Arruda, P. L. Viana, F. M. Santos, P. B. Mayer, T. J. Battituci & L. J. Arruda 826). A. Equatorial view. B. Polar view. C. Detail of mesocolpium and a section of the colpus. Borreria hispida (D–E from R. Spruce 663; F from A. Gröger 986). D. Equatorial view. E. Polar view. F. Detail of mesocolpium and a section of the colpus. Borreria semiamplexicaule (G–H from P. M. Burkowski, A. J. Arruda, P. L. Viana, F. M. Santos & T. J. Battituci 1187; I from D. Daly, R. Callejas, M. G. da Silva, E. Taylor, C. Rosario & M. dos Santos 1993). G. Equatorial view. H. Polar view. I. Detail of apocolpium. Borreria xanthophylla (J–L from J. J. de Granville, F. Crozier & C. Sarthou 15017). J. Equatorial view. K. Polar view. L. Detail of apocolpium. Scale bar 10 μm.