title: Morphological study of Ophidascaris excavata Hsü & Hoeppli, 1931 (Ascaridida: Ascarididae) from Gloydius brevicaudus (Stejneger) (Reptilia: Viperidae).
abstract: Ophidascaris excavata Hsü & Hoeppli, 1931 is a poorly known ascaridid parasite reported from the short-tailed pit viper Gloydius brevicaudus (Stejneger) (Reptilia: Viperidae) in China. In the present paper, the detailed morphology of this nematode was studied using light and scanning electron microscopy (SEM) based on newly collected material. The results revealed several important, but previously unreported, morphological features, including the presence of one pair of small, finger-like prolongations on each lip, narrow cervical alae beginning well posterior to the base of the ventrolateral lips and the second pair of postcloacal ventro-lateral papillae being double; in addition, there is no intestinal caecum. These supplementary morphological and morphometric data, especially the detailed morphological features obtained herein under SEM, would help us to understand the relationships of O. excavata with its congeners and enable us to diagnose this species more accurately.
authors.affiliation: Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Science, Hebei Normal University, 20 East Road of 2nd South Ring, Yuhua District, Shijiazhuang, 050024, Hebei Province, People's Republic of China. liangliangex369@126.com.
authors.forename: Liang
authors.initials: L
authors.lastname: Li
authors.affiliation: Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Science, Hebei Normal University, 20 East Road of 2nd South Ring, Yuhua District, Shijiazhuang, 050024, Hebei Province, People's Republic of China.
authors.forename: Wen-Ting
authors.initials: WT
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Science, Hebei Normal University, 20 East Road of 2nd South Ring, Yuhua District, Shijiazhuang, 050024, Hebei Province, People's Republic of China.
authors.forename: Hui-Xia
authors.initials: HX
authors.lastname: Chen
authors.affiliation: Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Science, Hebei Normal University, 20 East Road of 2nd South Ring, Yuhua District, Shijiazhuang, 050024, Hebei Province, People's Republic of China.
authors.forename: Yan-Ning
authors.initials: YN
authors.lastname: Guo
authors.affiliation: Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Science, Hebei Normal University, 20 East Road of 2nd South Ring, Yuhua District, Shijiazhuang, 050024, Hebei Province, People's Republic of China.
authors.forename: Lu-Ping
authors.initials: LP
authors.lastname: Zhang
mesh_terms: D000818:Animals; D017162:Ascaridida / Q000033:anatomy & histology / Q000145:classification* / Q000648:ultrastructure; D002681:China; D008855:Microscopy, Electron, Scanning; D013045:Species Specificity; D017819:Viperidae / Q000469:parasitology*