NGTS-14Ab compared to other planets within the Neptunian desert, as defined by Szabó & Kálmán (2019) (their ‘Region A’ is the area between the dashed black lines in Fig. 5). Planetary data are taken from the NASA Exoplanet Archive. NGTS-14Ab is denoted by a dark blue point in both panels. Upper panel: planet density versus orbital period. Several planets discussed in the text are labelled with their names. Lower panel: planet radius versus mass. The Solar System ice giants are indicated with their initial letters, and lines of constant density (1.0 and 2.0 g cm⁻³) are shown with solid pale blue lines. Two models from Zeng et al. (2019), corresponding to compositions of pure water (dashed blue line) and an Earth-like rocky core with an equal mass of water and five per cent hydrogen (dash-dotted red line), are also shown.