Convergent evolution W

The superorder any pill millipede belongs to is Oniscomorpha, named after their resemblance to terrestrial isopods who belong to the suborder Oniscidea. Their body plan is strikingly similar to an isopod's but they become easy to tell apart once you look at their number of body segments, head, and short stubby antennae. If you flipped one over, you wouldn't see a set of gills like isopods have either. For the body segments, Isopods always have 7 while pill millipedes have 11-13 tergites with two sets of legs for each. In the late Carboniferous, though, a now extinct order of these guys had about 15. They can roll into balls like some isopods, but actually beat them at this since they can tuck their head into the ball while isopods can't. Sucks to suck. Like the rest of the millipedes, they eat mostly decaying organic material. If you're in the northern hemisphere, we have ones from the order Glomerida that are much smaller than the giant pill millipedes in the southern hemisphere. Some of those, like Sphaeromimus musicus from Madagascar, can also make chirping sounds via stridulation! This is another thing they beat isopods at. More specifically if you're in the US, they appear (according to wikipedia) in 2 disparate areas: "An eastern, somewhat Appalachian region from Kentucky to northern Florida and Mississippi" and "a California region from the San Francisco Bay to the Monterey Bay". I live in the first area and have never seen one.