Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 1, 1996
Publication Date: N/A
Interpretive Summary: Continuing studies of the systematics of the ostertagiine nematodes resulted in revalidation of the genus Mazamastrongylus and recognition of morphological characters useful in its definition. Although the systematics of this subfamily of economically important nematodes remains unresolved, the present study is significant in providing new support for separation and recognition of three genera: Mazamastrongylus, Spiculopteragia and Sarwaria. Additionally the placement of M. peruvianus was confirmed and details of the surface cuticular ridges, and the genital complexes of males and females described for the first time. Description of these attributes support more refined studies for diagnostics and identification of pathogenic nematodes of ruminants.
Resurrection of Mazamastrongylus as proposed by Jansen (1986) was validated and placement of Mazamastrongylus peruvianus in this genus was confirmed, based on characters of the synlophe, copulatory bursa and spicules. The cervical synlophe consists of a strongly tapering pattern, and prominent "hood ridges" at the level of the excretory pore; there are 40 ridges at the midbody of males. The bursa is of the 2-2-1 type, with rays 2 and 3 parallel, and rays 4 and 5 of near equal length and only slightly divergent at the tips. The spoon-shaped dorsal process of the spicules, typical of M. peruvianus and other species of Mazamastrongylus is postulated as a synapomorphy for the genus. The genera Mazamastrongylus, Spiculopteragia, and Sarwaria are considered to be independent based on characters of the synlophe, spicules and copulatory bursa. Host and geographic distribution for species of Mazamastrongylus appears consistent with a history of coevolution and colonization and may parallel the pattern postulated for species of Nematodirus in cervids and camelids in the Neotropics.