Cave millipedes of the United States. XIV. Revalidation of the genus Speorthus Chamberlin, 1952 (Diplopoda, Polydesmida, Macrosternodesmidae), with a description of a new species from Texas and remarks on the families Polydesmidae and Macrosternodesmidae in North America Author Shear, William A. Author Reddell, James M. text Insecta Mundi 2017 2017-03-31 2017 529 1 13 journal article 10.5281/zenodo.4645845 1942-1354 4645845 D689DE8C-5140-4310-BF63-B5A8590E9E19 Genera of Polydesmidae in North America North of Mexico (Keyed in Shear 2012 ) Polydesmus Latrielle (4 species, all colonists from Europe), Brachydesmus Heller (1 species, native to Europe), Bidentogon Buckett and Gardner (2 species, California ), Calianotus Shelley (3 species, California ), Pseudopolydesmus (12 nominal species, eastern United States and southeastern Canada ), Scytonotus (9 species, eastern United States , southeastern Canada , Pacific Coast from Alaska to northern California, northern Rocky Mountains), Utadesmus (2 species, Utah, New Mexico), Snoqualmia (2 species, Washington, Idaho) and Retrorsia (2 species, western Oregon and Washington). There are several undescribed genera ranging from Washington to northern California.