Redescription of Elaeophora Schneideri Wehr and Dikmans, 1935 (Nematoda: Filarioidea).

Elaeophora schneideri Wehr and Dikmans, 1935, is redescribed on the basis of specimens obtained from Odocoileus hemionus, Odocoileus virginianus, Ovis aries, and Cervls canadensis. Recently Adcock, Hibler, Abdelbaki, and Davis (1965) reported that Elaeophora schneideri Wehr and Dikmans, 1935, caused blindness in North American elk (Cervus canadensis). This nematode is a common parasite of mule deer (Odocoileus hemionus) and domestic sheep (Ovis aries) in the mountainous regions of the western and southwestern United States, but has not been previously reported from elk. Specimens obtained from elk thus far are somewhat smaller than those found in sheep and deer, otherwise they are morphologically identical; moreover, except for the size of the specimens from elk, those from all three hosts are morphologically identical to the type specimens used by Wehr and Dikmans (1935). However an examination of the type specimens, and the specimens collected in the present study, has revealed several discrepancies in the original description. MATERIALS AND METHODS Redescription of E. schneideri is based on specimens obtained from deer, sheep, and elk. Some of those from mule deer were collected in Colorado by the late Dr. Lee Seghetti. The remainder were collected by one of us (C. P. H.) from mule deer and white-tailed deer (Odocoiletus virginianus) in Arizona, and mule deer in New Mexico. Specimens from sheep were collected in Colorado by Jensen and Seghetti (1955), and by one of us (C. P. H.) from sheep originating in the same general area. Specimens from elk were collected by the authors from animals in Arizona, Colorado, New Mexico, and Wyoming. Measurements of adults are based on five males and five females from each host, and are given in microns unless otherwise indicated, the average listed first, the range in parentheses. Illustrations Received for publication 13 May 1968. * This investigation was supported by research grant 5-R01-NB06199-02 from the NIH, Institute of Neurological Diseases and Blindness, and by the Arizona Came and Fish Commission. are based on specimens from the mule deer. Drawings were made with the aid of a camera lucida. Microfilariae were obtained by macerating skin in physiological salt solution. They were fixed in 70% alcohol, cleared in glycerin, and studied with the aid of a phase contrast microscope. Measurements are based on 25 specimens from the skin of mule deer. Redescription of Elaeophora schneideri Wehr and Dikmans, 1935 (Table I, Figs. 1-13)