Crystaltrok
Most mantitheres have adapted to eat crystal flora by developing a finch-like beak used to crush and pick at crystals. The crystaltrok, however, has found a novel and much more effective solution.
The crystaltrok’s radular spines are heavily modified, similar to those of the Ebony Crestbuck. Though the crystaltrok’s teeth are strong and cone-shaped, they are not used for piercing flesh. Rather, they are more like that of an artificial nutcracker, and are complete with a tough bony core. When the crystaltrok bites into a crystal, the crystal gets wedged between its upper and lower teeth, easily crushing it. The jaw is somewhat narrow, though still definitely wide enough to swallow chitinous chunks of crystal. The mouth isn’t the only thing adapted for eating crystals, however. The crystaltrok’s diamond-shaped hands are shaped just right for firmly gripping and eagerly tearing off octahedral crystal leaves.
While the crystaltroks do not outright replace the sentrok by themselves, they are a direct competitor to them, and a better adapted one at that. The remaining sentroks are mostly forced to eat purple flora in light of this new competition.