The images of Brans-Dicke-Kerr type naked singularities -

\begin{document}$ \omega>-3/2 $\end{document} represents naked singularities with distinct structures. For the case with

\begin{document}$ a \leqslant M $\end{document}

, the shadow in the Brans-Dicke-Kerr spacetime persists, gradually becomes flatter and smaller as ω decreases. Especially when

\begin{document}$ \omega<1/2 $\end{document}

, the shadow in the image exhibits a very special "jellyfish" shape and possesses a self-similar fractal structure. For the case with

\begin{document}$ a > M $\end{document}

, a distinct gray region consisting of two separate patches appears in the image observed by equatorial observers. This indicating that the Brans-Dicke-Kerr spacetime can be distinguished from the Kerr and Kerr-de Sitter cases based on its image. These effects of the Brans-Dicke parameter could help us to reveal the intrinsic structure of the Brans-Dicke-Kerr spacetimes and provide a foundation for testing Brans-Dicke theory through future high-precision observations."> The images of Brans-Dicke-Kerr type naked singularities -

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