Orthoporus is a genus of spirostreptid millipedes, containing around 80 species, distributed from the southern United States to Brazil and Argentina. \n* Orthoporus absconsus Chamberlin, 1922 \n* Orthoporus acanthethus Chamberlin, 1947 \n* Orthoporus ampussis (Karsch, 1881) \n* Orthoporus araguayensis Schubart, 1947 \n* Orthoporus asper (Attems, 1950) \n* Orthoporus bidens Schubart, 1945 \n* Orthoporus bisulcatus Chamberlin, 1952 \n* Orthoporus bobos Chamberlin, 1952 \n* Orthoporus boreus Chamberlin, 1947 \n* Orthoporus brasiliensis Schubart, 1947 \n* Orthoporus caelatus Loomis, 1936 \n* Orthoporus canalis (Chamberlin, 1925) \n* Orthoporus capucinus (Attems, 1950) \n* Orthoporus cayennophilus (Silvestri, 1897) \n* Orthoporus chihuanus Chamberlin, 1947 \n* Orthoporus chiriquensis Pocock, 19