Toxascaris

TOXASCARIS Leiper, 1907, a genus of nematodes of the subfamily Ascaridinae, family Ascarididae, order Ascaridata. The anterior end is provided with three lips. The pulp of the dorsal lip forms two lateral lobes, separated by a deep saddle-shaped depression, and an internal median lobe, which, unlike Toxascaris (see), is split into two lobes, the tips of which lie on the lateral lobes and completely do not cover the saddle-shaped depression. The cervical wings are less developed than in Toxascaris. The male caudal end is wingless, tapers to the tip, but does not form an additional conical appendage. The spicules of the male are almost equal, wingless, the vulva of the female is at the level of the anterior third of the body length. The eggs are almost round, with a thick smooth shell, without traces of reticulation. The genus includes two species: 1) T. leonina Linstow, 1902, which occurs in representatives of the cat and dog families and facultatively in humans (see figure), and 2) T. transfuga Rud., 1819 (from the bear). The length of the male T. leonina is 40-60 mm, width 0.9-1.25 mm; the length of the female is 65-100 mm, the diameter of the eggs is 0.085 mm. Cosmopolitan. In humans it occurs rarely. Leiper (Leiper, 1907) discovered it in Egypt, and Skrjabin, Podjapolskaya and Shul'ts (1929) in the USSR in the Far East among the Gilyaks. In the USSR there is another case registered by Pigulevskii, but Skrjabin and Shul'ts (1931) cast doubt on it.