Coronocyclus ulambajari n. sp. (Nematoda: Strongyloidea) from horses of Mongolia

Coronocyclus ulambajari n. sp. (Strongyloidea: Cyathostominae) from horses of Mongolia is described. The external leaf-crown (ELC) of the new species consists of 28 elements and the internal leaf-crown (ILC) of approximately 80 elements. A spindle-shaped (in optical section) mouth collar support is separated anteriorly from the buccal capsule and connected to it and elements of leaf-crowns by bundles of connective tissue. The buccal capsule is cylindrical, circular in cross-section, and approximately 3 times as wide as deep. A large, tongue-like dorsal cone protrudes from the floor of the buccal capsule overlying the large dorsal esophageal tooth. The duct of the dorsal esophageal gland opens at the tip of the dorsal cone. The tail and vagina of females are short, and the vulva is close to the anus. The buccal capsule and dorsal cone are most similar to Coronocyclus labratus, but differ significantly in size of dorsal cone and relative width and depth of the buccal capsule as well as characteristics of the leaf-crowns and female reproductive systems.