Distribution of orbital period versus radius for close-in exoplanets. The boundaries for the refined classification (Neptunian desert, ridge, and savanna; Castro-González et al. 2024a) are shown as dashed lines. Neptunes with well-measured 3D spin–orbit angles (precision better than 30° in the TEPCat catalog¹) are marked with crosses. Squares represent planets with (red edge) or without (magenta edge) escaping H/He detections. HAT-P-26 b is marked with a star. The radius and mass values are taken from the NASA Exoplanet Archive².