02249nas a2200265   4500008004100000020002000041245017800061210006900239260001200308300001400320490000700334520135000341653001101691653001301702653001001715653001301725653004001738653002501778653001101803653001101814653001001825100001501835700001701850856011601867       1998                        eng d  a1049233X (ISSN)00aDescription of Mediorhynchus papillosus (Acanthocephala: Gigantorhynchidae) from a Colorado, U.S.A., Population, with a Discussion of Morphology and Geographical Variability0 aDescription of Mediorhynchus papillosus Acanthocephala Gigantorh  c1998///  a189 - 2000 v653 aThe original description of Mediorhynchus papillosus Van Cleave, 1916 included misinterpretations of such taxonomically important structures as proboscis armature. The species was briefly redescribed from Asian material by Schmidt and Kuntz (1977) as well as by various Russian and other workers before and after 1977. The present collection from Colorado provided important taxonomic information previously unreported or erroneously interpreted. The first description of M. papillosus from North American specimens collected from a sage thrasher. Oreoscoptes montanus Baird, 1858, in Colorado, U.S.A., is presented with new features reported for the first time. A comprehensive comparison of the North American, Asian, and Russian populations is presented and discussed. Mediorhynchus papillosus appears to be a geographically variable species, particularly in size of proboscis and its armature, and relative space occupied by the neck and posterior proboscis. The geographically isolated Taiwanese population was markedly different from the Colorado population; the latter was more similar to others from various Soviet republics, particularly the Ukraine. Distinctiveness of geographical populations appears to be related to geographical restrictions, intermediate and definitive host specificity and distribution, and host feeding behavior.10aBrazil10aBulgaria10aChina10aColorado10aMediorhynchus papillosus morphology10aOreoscoptes montanus10aRussia10aTaiwan10aU.S.A1 aAmin, O.M.1 aDailey, M.D.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-2742551107&partnerID=40&md5=b1e4fd5717a2341d1018c3bac657a682