Metazoan parasites of Recurvirostra americana Gmelin (Aves), from southwestern Texas and Monte Vista National Wildlife Refuge, Colorado, with a checklist of helminth parasites hosted by by this species in North America

T-Nineteen species of helminth parasites and six species of ectoparasites were recovered from 33 American avocets, Revurvirostra ameriana Gmelin, collected from southwestern Texas and south-central Colorado. New host records are marked with an asterisk. The metazoan parasites are: Accacoeliidae, Cyclocoelum vanelli, Cyclocoelum lanceolatum,  yclocoelum tringae,* Notocotylus linearis,* Notocotylus stagnicolae,* Parastrigea mexicanus, Paramostomum malerischi,* Echinostoma revolutum,* Echinostoma sp.,* Parorchis  p.,* Cloacitrema sp., Diplophallus coili, Hymenolepis recurvirostrae, Hymenolepis cervotestis, Sobolevicanthu coloradensis, Diorchis recurvirostrae, Capillaria recurvirostrae,   evreuxia americana, Actornithophilus uniseriatus, Austromenopon micrandum, Cirrophthirus testudinarius Quadraceps semifissus, Quadraceps zephyra, and Rhinonyssus  imantopus. Diplophallus coili was the prevelant cestode and the prevalent helminth parasite, 93.9%. Sorenson's index of similarity for species of helminth parasites indicated that  he cestodes were the most simila group among three geographic areas (Kansas-Colorado to southwestern Texas, 100%; Kansas- Colorado to Monte Vista, Colorado, 90%1 and  outhwestern Texas to Monte Vista, Colorado, 90%). The helminth parasite community consisted mostly of dominant (8) and successful immigrant species (7). A checklist of helminth parasites reported for the American avocet from North America is also provided.