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We present a kinematical study of 314 RR~Lyrae stars in the solarneighbourhood using the publicly available photometric, spectroscopic, and {\itGaia} DR2 astrometric data to explore their distribution in the Milky Way. Wereport an overdensity of 22 RR~Lyrae stars in the solar neighbourhood at apericenter distance of between 5--9\,kpc from the Galactic center. Theirorbital parameters and their chemistry indicate that these 22 variables sharethe kinematics and the [Fe/H] values of the Galactic disc, with an averagemetallicity and tangential velocity of [Fe/H]=$-0.60$\,dex and $v_{\theta} =241$\,km\,s$^{-1}$, respectively. From the distribution of the Galactocentricspherical velocity components, we find that these 22 disc-like RR~Lyraevariables are not consistent with the {\it Gaia} Sausage ({\itGaia}-Enceladus), unlike almost half of the local RR~Lyrae stars. Chemicalinformation from the literature shows that the majority of the selectedpericenter peak RR~Lyrae variables are $\alpha$-poor, a property shared bytypically much younger stars in the thin disc. Using the available photometrywe rule out a possible misclassification with the known classical and anomalousCepheids. The similar kinematic, chemical, and pulsation properties of thesedisc RR~Lyrae stars suggest they share a common origin. In contrast, we findthe RR~Lyrae stars associated with the {\it Gaia}-Enceladus based on theirkinematics and chemical composition show a considerable metallicity spread inthe old population ($\sim$~1\,dex).

Evidence for Galactic disc RR~Lyrae stars in the Solar neighbourhood