Thanks!Narceus americanus (aka Giant Pinkfoot, American Giant Millipede, and probably ten other common names) is probably the most famous large American species, usually reaching about four inches. Their color patterns can vary broadly geographically, and so you have many options when buying online. Same general care as all other millipedes, though they like a healthy portion of deciduous leaves and moister habitats. For more detailed info I suggest searching the latin name, as this will give you lots of good articles and salespeople.
Thank you!Don't search google, use the board's search function with the scientific name. Should give you plenty of results. That said care is pretty standard. Moist substrate (not swampy), decaying hardwood/leaves, supplemental foods, etc.
This is a good thread on substrate: https://arachnoboards.com/threads/my-very-fussy-millipede-substrate.302303/#post-3023350