Location of local and intermediate redshift AGN and starbursts in the near-IR diagnostics defined in the paper: the Fe2S3–β, Fe2S3–α, P2S3, and C1S3 diagrams from left to right, as a function of [S III]/Paγ on the y-axis (top row) or [S III]/Paβ (bottom row). Sources coming from Riffel et al. (2006, 2019) are drawn with square symbols and triangles, respectively. Those presented and measured by Onori et al. (2017) are identified with empty stars, while starbursts from Calabrò et al. (2019) are shown with cyan hexagons. The underlying models are the same as described in Fig. 8.