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United States Department of Agriculture

Agricultural Research Service

Title: Ashworthius Patriciapilittae N. Sp. (Trichostrongyloidea: Haemonchinae), An Abomasal Nematode in Odocoileus Virginianus from Costa Rica, and a First Record for the Genus in the Western Hemisphere.

Authors
item Hoberg, Eric
item Abrams, Arthur
item Carreno, Ramon - UNIV. CALIFORNIA-DAVIS
item Lichtenfels, James

Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 11, 2002
Publication Date: December 10, 2002
Citation: Hoberg, E.P., Abrams, A., Carreno, R., Lichtenfels, J.R. 2002. Ashworthius patriciapilittae n. sp. (trichostrongyloidea: haemonchinae), an abomasal nematode in odocoileus virginianus from costa rica, and a first record for the genus in the western hemisphere. Journal of Parasitology 88:1187-1199.

Interpretive Summary: Although the nematodes of New World ruminants have been studied in detail, many species previously unknown to science remain to be discovered. Such undocumented biodiversity for parasites has implications for understanding the true distribution of a variety of parasites in both domestic food animals and wild ruminants that may serve as reservoirs for infection. In continuing studies of parasite biodiversity among ruminants, we report nematodes of the genus Ashworthius for the first time in the Western Hemisphere, and describe a new species, A. patriciapilittae, in white- tailed deer, Odocoileus virginianus from Costa Rica. The presence of Ashworthius in Costa Rica can be examined in the context of competing hypotheses for contemporary host-switching from domestic bovids or cospeciation in cervids. Either A. patriciapilittae has been introduced or is a component of an endemic Central and South American fauna that has diversified through coevolution of Ashworthius and cervid hosts. Most importantly, among haemonchines in the Western Hemisphere specimens of A. patriciapilittae may be confused with 3 species of Haemonchus, including H. contortus, H. placei and H. similis that occur as pathogenic parasites in both domestic and wild ruminants. Discovery of A. patriciapilittae emphasizes the continued need for survey and inventory to define the structure and distribution of parasite faunas in wild and domestic ruminants from the Nearctic and Neotropical regions.

Technical Abstract: Nematodes of the genus Ashworthius are reported for the first time in the Western Hemisphere, and A. patriciapilittae n. sp. is described based on specimens in white-tailed deer, Odocoileus virginianus from Costa Rica. Among 8 known species, A. patriciapilittae is morphologically similar to A. tuyenquangi in red muntjac, Muntjacus muntjak from northern Vietnam. The synlophe in A. patriciapilittae is composed of 26 ridges in the cervical zone, and is continuous to the caudal extremity in males and females. Males are characterized by a complex dorsal ray, and narrow trifurcate spicules (351-356 m long) lacking an "eyelet," and with dissimilar ventral and dorsal processes; the gubernaculum is 45-48% of spicule length. Females have a prominent linguiform flap at the vulva and large eggs (108-142 m long). The presence of Ashworthius in Costa Rica can be examined in the context of competing hypotheses for contemporary host-switching or cospeciation in cervids; either A. patriciapilittae has been introduced or is a component of an endemic Central and South American fauna that has diversified through coevolution of Ashworthius and cervid hosts. Among haemonchines in the Western Hemisphere specimens of A. patriciapilittae may be confused with 3 species of Haemonchus, including H. contortus, H. placei and H. similis that occur in both domestic and wild ruminants. Discovery of A. patriciapilittae emphasizes the continued need for survey and inventory to define the structure and distribution of parasite faunas in wild and domestic ruminants from the Nearctic and Neotropical regions.

Last Modified: 10/24/2014
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