The symbioship hum split from its ancestor the nuh-hum and moved to the sea. It lives inside the spore vent of the symbioship diamiboard. It has developed a symbiotic relationship with it. It uses its large sail leaves to guide the symbioship superorganism while the diamiboard gives it nutrients and fresh water from its red fungi-like insides.
The way it begin this symbiosis was some nuh-hum had a mutation that revered their floating spores back to airborne spores. Once airborne some made its way into the spore vents of the symbioship diamiboard. Those that survived were able to grow and over time those who had the no holes mutations of their distant marine ancestors survived the best.
It bottom leaves leave spaces between them so the symbioship diamiboard can release its spores into the air too. Since they need the symbioship diamiboard for water any that tip over quickly die of too much salt. Their bottom leaves still medicinal properties, but it have bitter taste.