Greater Lahn

The Greater Lahn replaced its ancestor. The only “grass” in its environment, it was able to grow exponentially in height in an arms race with itself to become the tallest, outcompeting its ancestor in the process. It failed to outcompete the related Lahnworm, as the Lahnworm’s mobility meant it could simply get up and move to avoid the Greater Lahn. Its leaves now have chitinous cell walls, allowing them to grow taller without also needing to become thicker; in fact, its leaves are thinner than those of its ancestor, and they branch. Similar to its ancestor, males live as mobile fauna but become immobile plant-like females later in life. Unlike its ancestor, the Greater Lahn very easily crossed rivers by chance dispersal and walking right across fallen trees. It can also be found in the high desert, females living in clumps wherever conditions are right.

The Greater Lahn has lost its bioluminescence, as it cost too much energy to maintain. Males instead mate with any female they come across as long as they have the sperm to do so throughout their spring mating season, leaving the health of any offspring up to luck. The inexplicable behavior of males carrying the eggs has also been lost, as it actually put the eggs in a lot of danger. Instead, females retain the eggs themselves in a subterranean oviduct. Indeed, the entire cloacal opening is underground to protect it from trampling and predation, and as such the male must dig for it. This is done using a retractable shovel-like phallus derived from the skin and upper “beak” of the cloaca, which is absorbed during the transition to female. Females can also produce clonal offspring through parthenogenesis. When eggs hatch, the babies dig their way to the surface and begin their lives as males, but at a little over three years of age they will bury themselves and become female.

Unlike its ancestor, females of the Greater Lahn are completely submerged underground apart from their leaves. This allows them to avoid being trampled to death and makes them far more difficult to pull from the ground and devour. Like their ancestor they use branching root-like limbs to hold them in place and a complex branching network consisting of a root-like structure derived from the tongue and esophagus to collect water and nutrients from the ground. The leg-roots can tangle with those of neighboring individuals, keeping them stable as a group.

When dehydrated, the Greater Lahn’s leaves turn blue-violet and eventually fade to pale pink. This is the result of their blood; as the blue pigment fades, the red color from the iron-based blood underneath begins to show, and when the blood is removed to conserve water, all that is left is the pinkish natural color of the flesh.