Ovule, seed and seedling characters in Acharia (Achariaceae) with evidence of myrmecochory in the family

An investigation of mature seed structure in Guthriea capensis and ovule-to-seed development in Acharia tragodes indicate that the two species are herbaceous myrmecochores with similar adaptations for seed dispersal and germination. The development and structure of the modified seed tissues, namely a sarcotestal elaiosome, a fringe layer in the mesotesta, endotestal-exotegmic mechanical layers and a chalazal seed lid are described. Additional embryological similarities between the two taxa include, amongst others, sessile ovules, distally lobed outer integuments, zigzag micropyle canals formed by both integuments, bisporic Allium Type embryo sacs, suspensorless embryos belonging to the Penaea Variation of the Asterad Type, and small embryos in the mature seed. In Acharia intraseminal embryo growth occurs before radicle emergence, germination is epigeal and seedlings belong to the Macaranga Type