First Record of the Rhadinorhynchus trachuri (Acanthocephala, Rhadinorhynchidae) Parasite on the Auxis rochei from the Marine Waters of Lattakia, Syria

Abstract

The aim of this research was to deal with identification of the types of endoparasites observed in the fish species A. rochei caught in the marine waters of Lattakia, the site of infection and prevalence of the parasites found during the current study to be protected from the damages of this parasite. They research was carried out in Department of Zoology, Faculty of Sciences, Latakia University between October 2021 and September 2023. during the research, 263 live specimens of A. rochei were collected; they were taken from the commercial fishermen from Ras Al Basit – Lattakia. All specimens were transferred fresh to laboratory of Hydrobiology in Faculty of Science at Latakia University. Eleven fish were infected by parasites. Fish were dissected and then their body cavities and internal organs were examined. Some parasites were observed inside intestines of some fish; these parasites were collected, counted, processed, examined and saved, and classified according to criteria applied in similar studies. Infection prevalence (%) and mean intensity follow the recommendations of (Bush et al., 1997).  In the result, 11 out of 263 examined specimens of A. rochei were infected with 27 parasites found in their intestines. The infection prevalence was 4.18% and its density was 2.45 parasite/ fish. Morphological features (body, eggs, and hooks) of Rhadinorhynchus trachuri agreed with study of Amin (2020). Worms collected were mature females with an orange color, body composed of proboscis, neck and trunk. trunk elongated, sub-cylindrical, somewhat swollen anteriorly, a spinose, and covered with transverse striated cuticle. Proboscis is cylindrical, stout, claviform, densely armed with 12 alternating rows of strongly re-curved 23–25 hooks. In conclusion, the result of this study showed the presence of the parasite R. trachuri inside the intestines of the A. rochei fish that inhabiting the marine waters of the Syria coast of Lattakia. This is the first record of infection of A. rochei fish by R. trachuri in Mediterranean Sea generally and Syrian marine waters especially. In our knowledge, this article will contribute to the ichthyhelminthological studies of marine fish in Syria.