On the Striking Biomorphological Convergence within the Ecobiomorph Group “Isoetids”
摘要
Based on the example of several species from the isoetid ecobiomorph group (Isoёtes lacustris L., I. echinospora Durieu, Lobelia dortmanna L., and Subularia aquatica L.), we have shown a striking convergence of biomorphological, anatomical, and physiological features in representatives of different life forms from different families (Isoëtaceae, Lobeliaceae, and Brassicaceae), as well as from different orders (Lycopodiophyta and Magnoliophyta) of the Plant Kingdom. We discuss the rate of convergence of isoetid features in representatives of different taxonomic groups with a predominant emphasis on Lobelia dortmanna, in particular, a less studied annual isoetid, Subularia aquatica, which are manifested at different stages of ontogeny. The resemblance of Lobelia and Subularia seedlings with their collet (collar) covered with rhizoides is shown. The extremely wide development of aerenchyma in all vegetative organs, including roots, is represented in two forms, in the form of radial lysigeny and in the form of honey combs