Morphometric analysis and genetic identification of Hysterothylacium larvae (Nematoda) in marine fish in the Aegean Sea

Year 2026, Volume: 73 Issue: 1, 23 - 31, 01.01.2026

Ünver Oğuzhan Tekay , Gökmen Zafer Pekmezci

https://doi.org/10.33988/auvfd.1721007

Abstract

The classification of Hysterothylacium larval types in the Aegen Sea (FAO fishing area 37.3.1) is incomplete and still requires further investigation. This study aimed to offer morphological identification, supported by entire ITS sequence data, of Hysterothylacium larval types infecting six out of sixteen commonly consumed marine fish species from the Aegean Sea: Boops boops, Trachurus mediterraneus, Spicara maena, Upeneus moluccensis, Engraulis encrasicolus, and Sardina pilchardus. This study describes three morphotypes IV, V, and VIII in the Aegean Sea for the first time using both morphological and genetic data. We also report Spicara maena as new hosts for larval morphotype V. Herein, the presence of potential zoonotic larval type VIII has been found in B. boops, E. encrasicolus, and S. pilchardus in the Aegean Sea, and may pose a public health risk.

Keywords

Aegean Sea , Hysterothylacium morphotypes , ITS , Sequencing

Ethical Statement

not required

Supporting Institution

The Scientific Research Council of Ondokuz Mayis University, Samsun, Türkiye

Project Number

PYO.VET.1904.23.022

Thanks

-

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