From 2speccers2tools wiki

Following the proliferation of Greater Poralp Tree groves, it was only a matter of time before organisms adapted to exploit them. One such organism is the Pigbug, which split from a population of Armorpigs which had wandered into the warm coasts.

To get into the tough stems of the poralps, the Pigbug’s lip projections are sclerotized with hard chitin, allowing it to scrape off chunks of its meal and heave them into its mouth. In order to facilitate digesting the tough, cellulose-based supports of the poralps, the boxy shape of the Pigbug has elongated into a rectangular configuration to house a more ample gut which can secrete specialized enzymes for breaking the stuff down. These traits give it the ability to extract more nutrients from such a tough meal while still able to consume detritus and smaller organisms as supplement.

True to the Pigbug’s name, the other most obvious adaptation is its chitin plate integrating with the rest of its body to form a proper exoskeleton. As predatory ‘pigs occur in decent numbers in the warm coasts, expanding the plate into an exoskeleton proved to be a major defensive benefit. An exoskeleton is also crucial in that it doesn’t sacrifice any ancestral mobility.

Like its predatory relative, its photoreceptors have improved considerably, able to detect color, and blurry shapes and movement, enabling it to better differentiate food from foes. Gills have developed to improve respiration. Within the Pigbug’s upper-rear corners are its gonads, which expel gametes if two receptive Pigbugs meet, forming a spore which in turn produces a tiny larva.