Morphology and molecular identification of Anisakis typica larvae in layang fish (Decapterus russelli) from the northern Java Sea off Jakarta, Indonesia

Nanis Nurhidayah (Research Center for Veterinary Science, Research Organization for Health, National Research and Innovation Agency (BRIN), 16911, Bogor, Indonesia)
Esdinawan Carakantara Satrija (Biomedicine Study Program, School of Veterinary Medicine and Biomedical Sciences, IPB University, 16680, Bogor, Indonesia)
Ridi Arif (Division of Parasitology and Medical Entomology, School of Veterinary Medicine and Biomedical Sciences, IPB University, 16680, Bogor, Indonesia)
I Wayan Teguh Wibawan (Division of Medical Microbiology, School of Veterinary Medicine and Biomedical Sciences, IPB University, 16680, Bogor, Indonesia)
Risa Tiuria (Division of Parasitology and Medical Entomology, School of Veterinary Medicine and Biomedical Sciences, IPB University, 16680, Bogor, Indonesia)
Sri Murtini (Division of Medical Microbiology, School of Veterinary Medicine and Biomedical Sciences, IPB University, 16680, Bogor, Indonesia)
Sayu Putu Yuni Paryati (Faculty of Medicine, University of Jenderal Achmad Yani, 40285, Cimahi, Indonesia)

Jurnal Medik Veteriner
Vol. 9 No. 2 (2026): October

Anisakidosis, a fish-borne zoonosis, is caused by the ingestion of Anisakidae larvae in undercooked or raw fish dishes. Identification of third-stage larvae (L3) of Anisakidae in marine fish could contribute to disease prevention. This study aimed to identify the morphological and molecular characteristics of L3 Anisakis larvae from one of the Indian scads, Decapterus russelli, locally known as layang fish, obtained from the northern Java Sea off Jakarta, Indonesia, and sold at a traditional market in Bogor, West Java. Morphological and morphometric analyses were conducted using light microscopy and scanning electron microscopy (SEM), while molecular identification was performed using multiplex polymerase chain reaction (PCR) targeting the 18S rRNA, ITS1, 5.8S, and ITS2 regions, followed by a neighbor-joining (NJ) analysis based on pairwise genetic distances using the Kimura 2-parameter model and 1,000 bootstrap replicates. A total of 378 L3 Anisakis larvae were recovered from 38 layang fish and were found in the body cavity, liver, intestine, and gills. The prevalence and mean intensity were 78.95% and 11.48 (95% CI = 10.97–12.00), respectively. Morphological and morphometric analyses using light microscopy revealed a boring tooth, triangular lips, an esophagus, ventricles, and a mucron. SEM confirmed the structures of these organelles and the presence of transverse and longitudinal striations on the larval surface. Molecular analysis confirmed that the larvae were A. typica in layang fish and showed close genetic similarity to A. typica from other regions of Indonesia.