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The abundance of compact, massive, early-type galaxies (ETGs) providesimportant constraints to galaxy formation scenarios. Thanks to the areacovered, depth, excellent spatial resolution and seeing, the ESO Public opticalKilo Degree Survey (KiDS), carried out with the VLT Survey Telescope (VST),offers a unique opportunity to conduct a complete census of the most compactgalaxies in the Universe. This paper presents a first census of such systemsfrom the first 156 square degrees of KiDS. Our analysis relies on g-, r-, andi-band effective radii ($R_{\rm e}$), derived by fitting galaxy images withPSF-convolved S\'ersic models, high-quality photometric redshifts, $z_{\rmphot}$, estimated from machine learning techniques, and stellar masses, $M_{\rm\star}$, calculated from KiDS aperture photometry. After massiveness ($M_{\rm\star} > 8 \times 10^{10}\, \rm M_{\odot}$) and compactness ($R_{\rm e} < 1.5\, \rm kpc$ in g-, r- and i-bands) criteria are applied, a visual inspection ofthe candidates plus near-infrared photometry from VIKING-DR1 are used to refineour sample. The final catalog, to be spectroscopically confirmed, consists of92 systems in the redshift range $z \sim 0.2-0.7$. This sample, which we expectto increase by a factor of ten over the total survey area, represents the firstattempt to select massive super-compact ETGs (MSCGs) in KiDS. We investigatethe impact of redshift systematics in the selection, finding that this seems tobe a major source of contamination in our sample. A preliminary analysis showsthat MSCGs exhibit negative internal colour gradients, consistent with apassive evolution of these systems. We find that the number density of MSCGs isonly mildly consistent with predictions from simulations at $z>0.2$, while nosuch system is found at $z < 0.2$.

Towards a census of super-compact massive galaxies in the Kilo Degree Survey