Prevalence of Black Gill ( <i>Hyalophysa lynni</i> ) in White Shrimp <i>Litopenaeus setiferus</i> and Brown Shrimp <i>Farfantepenaeus aztecus</i> along the Texas Gulf Coast

Abstract Shrimp black gill is an emerging disease caused by a parasitic ciliate, Hyalophysa lynni , that attacks tissue in white shrimp Litopenaeus setiferus and brown Farfantepenaeus aztecus induces immune response produces melanized gills. This causes necrosis damage tissue, which limits metabolic capability can lead to high predation mortality among infected individuals. was first observed the southeast Atlantic fishery United States, this ciliate has been increasing prevalence populations of region since 2000. The Gulf Mexico, with its lucrative extended warmwater conditions during year, potential for H. spread. White were sampled from seven major bays along coast Texas March November 2019 underwent PCR analysis detect presence tissue. From November, 65% collected samples tested positive . Samples all upper‐coast having significantly higher than lower‐coast bays. Both ; however, had prevalence. Overall, showed temporal pattern low spring, peaking late fall. Generalized additive mixed models detected water temperature salinity level 30‰ or less as significant contributors study validates commonality western serves baseline future sampling efforts region, contributes understanding management threats fishery.