Embryo sac development in some South African Lantana species (Verbenaceae)

Abstract

Evidence that the South African Lantana camara L. complex only produces sexual embryo sacs is provided. It is shown that the archesporium occasionally divides mitotically and that both archesporia form tetrads. The chalazal megaspore of one tetrad and the micropylar megaspore of the second tetrad develop into Polygonum type embryo sacs.

L. rugosa Thunb. also forms Polygonum type embryo sacs. The L. rugosa embryo sac has a much more densely packed cytoplasm, smaller vacuole and the position of the polar nuclei differs from that of the L. camara embryo sac. It is possible to distinguish between  L. camara and  L. rugosa on their embryo sac morphology alone.