Setyobudi E, Rohmah I, Syarifah RF, Ramatia L, Murwantoko, Sari DWK. 2019. Presence of Anisakis nematode larvae in Indian mackerel (Rastrelliger spp.) along the Indian Ocean southern coast of East Java, Indonesia. Biodiversitas 20: 313-319. In this study, we aimed to determine the prevalence (P), mean intensity (MI) and site of infection of anisakid larvae (Nematoda) in Indian mackerel (Rastrelliger spp.) at the Indian Ocean Southern Coast of East Java. A total of 341 fish were collected from Prigi and Muncar Fish Harbor, East Java during March-April 2018. Each fish specimen was measured in body length and weight, and then dissected for examination of Anisakis larvae in the body cavity, digestive tract, liver, gonad and muscle. The collected larvae were preserved in absolute ethanol for both morphological and molecular identification. The results of this research showed Indian mackerel was susceptible to Anisakis infection (P=17%, MI =6.8 larva/individual fish). Most of the larvae were found in the digestive tract and body cavity, 47.2% and 46.0% respectively. Only a few larvae were found in other internal organs and muscle. Based on morphological identification, these larvae corresponded to Anisakis Type I. Furthermore, in molecular identification using PCR-RFLP, the banding pattern clearly matched with Anisakis typica. The prevalence and mean intensity of Anisakis nematodes on Indian mackerel along the southern coast of East Java seem to be different in each locality and from other adjacent waters as has previously been reported, which may be due to differences in feeding habits and in the distribution of marine mammals as the final host. The results suggest that differences in prevalence and mean intensity of anisakis larvae infection could be developed as a biological indicator of fish stock discrimination. However, clear information regarding food habits of Indian mackerel and migration patterns of the paratenic hosts as well as of marine mammals as final host is needed.

Abstract. Setyobudi E, Murwantoko, Utami AMR, Syarifah RF. 2023. Anisakid nematodes from the largehead hairtail fish (Trichiurus lepturus) from the northern coast of Java, Indonesia. Biodiversitas 24: 1560-1568. Hairtail fish has been frequently reported to be infected by anisakid nematodes. This study aims to determine the presence of anisakid nematodes on the large-head hairtail fish (Trichiurus lepturus) from the northern coast of the Java Sea, Indonesia. In total, 306 hairtail fish were collected from the northern coast of Java. Each fish sample was measured its length and weighed, then dissected to examine the presence of anisakid nematode. The anisakid larva examination was conducted in the body cavity, internal organs, digestive tract, and muscles. The anisakid nematodes found were then separated and grouped based on morphological appearance, namely body color and size. Selected samples from each anisakid group and sampling location were extracted and identified molecularly by the direct sequencing method. The findings showed that the larvae of anisakid nematodes infect the T. lepturus with different prevalence and average intensity at each location (P: 38.0-100%, MI: 3.33-42.88 larvae/ind.). Mostly anisakid larvae were found in the body cavity and were not found in the muscle. Most of the T. lepturus from the northern coasts of Cirebon and Pati were infected with anisakid at low intensity (?5 larvae/individual). The high intensity of anisakid larval infection was shown by the hairtail originating from Rembang and Tuban (>20 larvae/ind.). Molecular identification showed that three anisakids were isolated from hairtails from the northern coast of Java, namely Anisakis typica, Hysterothylacium amoyense, and Raphidascaris lophii. Information on anisakid species and their distribution is important as a reference for fish handling and processing, the assessment of the human health risk, and the development of these nematodes as biological tags.