2025MNRAS.537.3234T

V498 Hya (SDSS J084555.07+033929.2) was identified as a short-period cataclysmic variable (CV) by the Catalina Real-Time Transient Survey (CRTS) in 2008. The superhump period was measured during the detected single superoutburst of V498 Hya. The quiescent spectrum subsequently taken by the Sloan Digital Sky Survey-V Milky Way Mapper survey suggested that the CV donor may be a brown dwarf. We present time-resolved follow-up spectroscopy of V498 Hya in quiescence, obtained with the Gran Telescopio Canarias (GTC) Optical System for Imaging and low-intermediate-resolution Integrated Spectroscopy (OSIRIS) spectrograph, from which we derived the 86.053 min spectroscopic period, systemic radial velocity, and the gravitational redshift of the Mg II line. We also modelled the spectral energy distribution to constrain the system parameters, including the ≥0.82 $\mathrm{ M}_\odot$ mass of the white dwarf and the best-fitting value $0.043\pm 0.004\ \mathrm{M}_\odot$ of the donor star mass. This combination of parameters implies that V498 Hya has evolved past the period minimum and is a relatively rare 'period bouncer'.