The North American genus Malporus Casey is revised for the first time.
Three species are found in the eastern North America, and are most co
mmonly collected in riparian areas or in salt marshes: M. cinctus (Say
), M. formicarius (LaFerte-Senectere), M. properus Casey. A new specie
s from the Southwestern United States, M. werneri, is described, and M
. blandus Casey is here placed as a junior synonym of M. properus, new
synonym. Anthicus formicarius LaFerte-Senectere is designated as the
type species of Malporus.