Morphological and Genetic Characterization of the Poorly Known Species Subulura chinensis Schwartz, 1926 (Nematoda: Ascaridida) from Athene noctua (Scopoli) (Strigiformes: Strigidae).

Introduction: Subulura chinensis Schwartz, 1926 is a hitherto poorly known nematode species. The morphology of S. chinensis has not been sufficiently well described. In addition, the molecular data from species of the Subuluroidea are extremely limited.

Methods: The detailed morphology of S. chinensis was studied using light microscopy and, for the first time, scanning electron microscopy, based on newly collected specimens from the little owl Athene noctua (Scopoli) (Strigiformes: Strigidae) in China. The internal transcribed spacer (ITS) of ribosomal DNA and mitochondrial cytochrome c oxidase subunit 1 (cox1) target regions of S. chinensis were first amplified by polymerase chain reaction (PCR), then sequenced and analysed for the molecular identification of this species.

Results: Our SEM observations showed for the fist time the detailed morphology of the cephalic extremity, precloacal pseudo-sucker, caudal papillae, gubernaculum, phasmids and vulva of S. chinensis, and also determined the presence of a small, single medio-ventral precloacal papilla in the male. Moreover, we detected the presence of 0.08-0.40% and 0-1.30% nucleotide divergence among different individuals of S. chinensis in the ITS and cox1 regions, respectively. The supplementary morphological characters and genetic data will be very useful for the diagnosis of this poorly known species.