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Licensed Unlicensed Requires Authentication Published by De Gruyter January 17, 2018

Morphological and molecular characterization of Seuratascaris numidica (Seurat, 1917) (Ascaridida: Ascarididae)

Hui-Xia Chen, Kuang Zhang, Lu-Ping Zhang and Liang Li
From the journal Acta Parasitologica


Seuratascaris numidica (Seurat, 1917) is a specialized nematode species parasitizing amphibians only. In the present study, the detailed morphology of this poorly known species was studied using light and scanning electron microscopy based on the newly material collected from Hoplobatrachus chinensis (Osbeck) (Amphibia: Anura) in China. We found that the relative length of intestinal caecum in our male specimens (representing 68.4–71.1% of oesophageal length) is slighter longer than the previously reported data (not over 60.0% of oesophageal length). Our SEM observations also revealed the presence of ca. 64–76 small conical denticles on each lip. In addition, Angusticaecum wuyiensisWang, 1981, collected from Rana schmackeri Boettger (Amphibia: Anura) from Wuyi Mountain in Fujian Province, China was considered as a new synonym of S. numidica. The ITS and cox1 sequences of S. numidica were also sequenced for the first time and there is no nucleotide variability detected in both regions. The present supplementary morphological and molecular data (especially the ITS and cox1 sequences) obtained herein is extremely important and useful to determine the morphological variability, population genetics and phylogenetic position of S. numidica in the future.


This study was supported by the National Natural Science Foundation of China (NSFC-31572231), Natural Science Foundation of Hebei Province (NSFH-C2016205088) and the Youth Top Talent Support Program of Hebei Province for Dr. Liang Li.


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Received: 2017-10-27
Revised: 2017-11-6
Accepted: 2017-11-8
Published Online: 2018-1-17
Published in Print: 2018-3-26

© 2018 W. Stefański Institute of Parasitology, PAS