2 
Rowland M. Shelley 
Millipeds of the genus Scytonotus are common inhabitants of 
forests in eastern and western North America. The small, pink, tu- 
berculate polydesmids are often encountered on the undersurfaces 
of wet bark, twigs, and pieces of wood, sometimes in or very 
close to standing water, and are more prevalent in cooler seasons 
of the year. Scytonotus is one of four disjunct diplopod genera 
with representatives on both sides of the continent, the other being 
Ergodesmus (Polydesmida: Nearctodesmidae), Orinisobates (Julida: 
Nemasomatidae), and Brachycybe (Platydesmida: Andrognathidae) 
(Hoffman 1962a, 1975; Gardner 1975; Enghoff 1985). Scytonotus 
occurs in four separate areas (Fig. 1): 1) the eastern United States 
and southern Ontario and Quebec, Canada, east of the Central Plains; 
2) the Wasatch and Teton mountains, and associated ranges, of 
northern Utah, eastern Idaho, and western Wyoming; 3) the Rocky 
and Selkirk mountains, and associated ranges, of northern Idaho, 
western Montana, eastern Washington, and southeastern British 
Fig. 1. Distribution of Scytonotus. A smooth line has been drawn around 
range extremes in all directions in each of the four areas. 
