Brackish Taxonotree
3 meters tall
Originated in Zone 3 (primarily around the mouth of Zone 16 at depths between 4 and 50 meters)
As populations of Laminaralga megafolium began to face interspecific competition as well as competition from Laminaralga magnideus for space and available nutrients in the sediment, they began to inhabit areas previously unoccupied by other members of the genus. This eventually led some populations to colonize the area around Zone 16's opening, but they were not fully capable of living within Zone 16 itself. Facing increasing selective pressures due to interspecific competition, the populations around the river system eventually were forced in, evolving adaptations to handle this new way of life.
As populations of Laminaralga megafolium got pushed towards the mouth of Zone 16, they faced several different problems. Two of these problems were firstly the shallower depths as they got closer to land along with the powerful currents of the river presenting the risk of them toppling over. The ancestors of the Brackish Taxonotree (Laminaralga amnigigas) handled the first one by getting smaller, as smaller individuals in their ancestral populations were able to inhabit shallower waters and thus were favored. To deal with the problems of being toppled over, the energy once used for the impressive stems was now repurposed for the evolution of a relatively simple but large root system. It may not be able to stop them from toppling deeper within the river, but it works well enough for the Brackish Taxonotree to remain stable at the mouth of Zone 16.
Another problem the ancestors of the Brackish Taxonotree faced was the fact the waters at the mouth are not fully salt water and instead brackish. While their ancestors could survive such conditions, they did not necessarily thrive and often were sickly. To overcome this obstacle, the ancestors of the Brackish Taxonotree evolved the ability to lower the target amount of salt in their cells which thus allowed them to avoid over-hydrating in the lower-salinity environments they inhabited. This adaptation is possible through the use of salt bladders, epidermal cells with enlarged vacuoles which salt is pumped into and released back into the water.
Much like their ancestors, the Brackish Taxonotree continuously grows seed pods at the side of its stem that loosen with age and eventually drop off. These seed pods provide an ideal food source for many kinds of muscals and luring both marine and freshwater species over. While the high predation means few of the seeds reach maturity, they are relatively safe once they do and their high reproductive rates counters this problem. The seeds are, however, slightly larger and denser, so they don't get carried away by the currents as far as their ancestors since their range is much more specific.