Orthoporus

With 117 accepted species this is a large genus spread across southern, central, and northern America, though only a small number of species have been kept in captivity, and the genus is in need of a revision to account for specimens that do not fit with current descriptions. O. ornatus, O. texicolens, O. cavicollis and O. lomontii have all been widely distributed in the American and European hobbies, though the latter two appear to have disappeared from the hobby since being introduced into Europe in the 2000s (incidentally, they are also the only two species demonstrated to have been bred repeatedly by enthusiasts). A fifth species, O. sp. "Guadeloupe", has recently been brought into the hobby by a French breeder, and a sixth species, O. flavior, has been collected by an American breeder. Numerous other specimens, possibly representing other species, have been collected on the southern border of the United States but not been established in captivity.

North American Orthoporus do well under standard millipede care with slightly drier than usual substrate along with good ventilation (which can be skipped over with many other round millipedes to maintain moisture), and are amongst some of the few millipedes that will bask for warmth in the sun or under a heat lamp. According to a number of reports, O. ornatus is frequently day-active. Despite their ubiquitousness in the American side of the hobby for decades, for many years enthusiasts were unable to get offspring from captive adults, and as such all specimens available were (and still are for the most part) wild caught. Recently, a few enthusiasts have reported seeing babies in their Orthoporus colonies, though these claims have largely fallen by the wayside as photographs of the babies growing into larger immatures have failed to materialize. The Wikipedia page on O. ornatus cites two European breeders as being the first to captively breed this species, though the citation goes to Richard Hoffman's entry for the species in his Checklist of the Millipeds of North and Middle America, which makes no mention of either supposed breeder or even captive keeping in general. It is hypothesized by the editors here that this species likely needs seasonal variation, similar to African Spirostreptidae, in order to be induced to breed consistently; a few reports have been verified of captive breeding (namely of texicolens) without seasonal variation but this feat cannot be repeated consistently. Very little is currently known about the captive keeping of South and Central American Orthoporus at this time.

Orthoporus ornatus comes in two (supposed) color forms; one that is a uniform chocolatey brown color (similar to O. guineensis) with brown legs, and one that is bright yellow with light brown bands and reddish legs, the latter of which regularly reaches to over 6"/15.2 cm. O. texicolens is dark brown with dark bandings and brown legs, while O. flavior is a bright yellow with pale banding and pale yellow legs. O. lomontii is a green color with dark green bandings and green legs, with O. sp. "Guadeloupe" looking like a much darker brown-and-green version. O. cavicollis is a dark brown to black creature with reddish-brown banding and reddish legs.