Morphological and molecular characterization of ascaridoid nematodes in the greater lizardfish, Saurida tumbil,from the Persian Gulf, Iran

The greater lizardfish, Saurida tumbil has been known as one of the most commercially important species in the Persian Gulf. A total of 240 specimens from the Persian Gulf were examined for infection with nematode parasites from January to December 2015. Detailed microscopy of specimens followed by characterization of the first and second internal transcribed spacers (ITS-1 and ITS-2, respectively) showed that they belong to two taxa that could be potentially zoonotic. Anisakis type I was found in the present study, had identical ITS sequences as Anisakis typica previously reported in Australian waters and was different from those reported in the Nearctic. Hysterothylacium larva was also found which had identical ITS sequences and similar morphology to those previously identified as H. amoyense in China Sea. Since no ITS sequence data from a well identified adult H.amoyense with an identifiable museum voucher number is yet available, we assigned this larva from the China Sea and the Persian Gulf to H.amoyense is doubtful until future studies on a well identified male reveals the identity of this larva so We suggest this larval type as Hysterothylacium larval type XV. Since anisakid larvae are considered as emerging zoonotic nematodes they definitely require specific identification for public health purposes.

Keywords:

Saurida tumbil , Anisakis sp. , Hysterothylacium sp. , Nematoda , Persian Gulf