Final answer:
Myriapods are unique from other arthropods due to a range of leg numbers from 10 to 750, having a single pair of antennae and mostly uniramous legs. Centipedes are predators with one pair of legs per segment, while millipedes are detritivores with two pairs per segment.
Step-by-step explanation:
Myriapods, which form the subphylum Myriapoda, are distinct from other arthropod clades by having a diverse range of leg counts, from as few as 10 to as many as 750. The subphylum includes species such as millipedes and centipedes. Myriapods have a single pair of antennae and mandibles for mouthparts, contrasting with crustaceans that typically have two pairs of antennae and biramous appendages.
Centipedes, or chilopods, have one pair of legs per segment and are predatory with forcipules for injecting poison. Millipedes, or diplopods, have two pairs of legs per diplosegment and are generally herbivores or detritivores. Symphylans and pauropods, two less well-known classes, resemble centipedes and millipedes respectively but have differences in leg segments and feeding habits.
Myriapods are predominantly terrestrial and thrive in moist environments such as forests, aiding in the breakdown of decaying plant material. Their ecological roles vary from predators such as centipedes to decomposers like millipedes and pauropods.