Derived from lesser knightworms living closer to shore, the beach knightworm evolved as a result of lesser knightworms being washed onto land as a result of wave action throwing them from the safety of their crystal clusters.

The beach knightworm had little trouble adapting to the open air. Its tracheal system was capable of transferring oxygen into the hemocoel regardless if it is submerged in water or not. However, this ability to transfer oxygen only can continue of the trachea remain moist, and as the beach knightworm spends more time on land, the more the trachea dry. As a result, their time on land is limited, and they must retreat to the water before they suffocate. However, this is of little issue, as their current form of locomotion allows them to inch back into the ocean. In addition to this, they must also return to a stand of colony crystals so that they can keep their shells from overgrowing.

While the beach knightworm initially retreated back into the water immediately after being washed up, eventually a new behavioral pattern emerged. The massive amount of corpses and detritus washed ashore proved to be a tantalizing food source for the beach knightworm. Eventually, some specimens began to spend more time on land, feeding on the feast presented by the corpse-strewn beach, only returning to the water to breed, replenish the moisture in their tracheal system, and erode their ever-growing exoskeleton. However, because this erosion takes some time, the beach knightworm may spend days in their ancestral home, feeding on the mycelium as their exoskeleton erodes in the enzyme bath excreted by the colony crystal. Because they spend more time outside of the crystal patches, the beach knightworm has taken on a dull orange coloration as means of camouflage in their relatively barren, wave-ravaged environment.

When the time comes to mate, the beach knightworm will return to the crystal patches they once frequented. Like their ancestor, they will dig nests to lay their eggs in. However, because their exoskeleton grows at a slower rate, they will be killed if they live among the colony crystal's mycelium for too long. As a result, their nests are made on the edges of the stands, where the influence of the colony crystal's mycelium is less overpowering. Their mating and parenting methods are near-identical to their ancestors, with cleaning the nest of mycelium being less of a problem. However, they must face a new challenge, as their nests are far more exposed than that of their ancestors. As a result, they have developed longer and sharper antennae-limbs to help ward off predators. However, this only works to a limited degree, as some predators are too large to easily ward off. However, their spikes make for an effective deterrent to these larger predators, decreasing predation rates to a certain extent.