Cestodes of the genus Hymenolepis Weinland, 1858 (sensu lato) from bats in North America and Hawaii

Hymenolepidid cestodes obtained through the examination of 539 vespertilionid hats repre-senting 15 species and five genera, collected in three regions of North America and on the Islandof Hawaii, were studied. Three species of the genus If ymenolepis Weinland, 1858 sensu lato.previously known from nearctic Chiroptera, are redescrihed: II. christensoni Macy. 1931, II.roudabushi Macy and Rausch, 1946, and H. • gertschi Macy, 1947. A fourth, H. lasinnyeteridissp. nov., recorded from hats of eight species in North America and Hawaii. is described anddistinguished morphologically from the other species of /Iymenolepis s.l. characterized in part bythe presence of an armed rostellum and occurring in hats. The presence of this cestode in theHawaiian hoary bat, Lasiurus cinereus semotus (Allen)• indicates that at least some of theprogenitors of the population on the Island of Hawaii were migrants of western North Americanorigin. The zoogeography of cestodes in hats is briefly discussed.