Morphological Characteristics of Parasitic Nematodes Trichuris sylvilagi (Nematoda, Trichuridae)

Morphometric parameters are analyzed and systematized of parasitic nematodes of the species Trichuris sylvilagi Tiner, 1950, obtained from Lepus europaeus (Pallas, 1778). The following parameters are suggested for the exact identification of female T. sylvilagi nematodes: the sizes of body, its anterior and posterior parts, width of body at the connection of esophagus and intestine, specific location of vesicular cuticular protrusions and vulva. Five metric parameters are established for the nematode eggs. The egg shell thickness, length and width of egg plug are suggested for use in addition to the length and width of eggs. Males of T. sylvilagi had strongly curved tail end, long spicule, and transparent spicule sheath which bears spines, and a bulbous inflation in its proximal part. The thirteen metric parameters, which we found to be of identification value for males, include sizes of body, length and width of its anterior and posterior parts, width of body at the connection of esophagus and intestine, sizes of spicule at various areas, and location of the vesicular cuticular protrusions. Obtained data on the metric studies of T. sylvilagi nematodes are compared with the published data.