The High-resolution Coronal Imager (Hi-C) observed short-lived tiny elongated loop-like structures in plage areas at an unprecedented spatial scale of 0.1"/pixel, which were invisible to previous instruments with more moderate resolution. We combined simultaneous, co-spatial HMI magnetograms and AIA UV and EUV images to investigate the nature of these features. Studying their motion, size, and lifetime we find that the miniature loop-like structures are closely connected to the evolution of the granulation in the photosphere and the related underlying small-scale magnetic field. Employing a DEM inversion based on the the EUV images from AIA we find that the temperature above and surrounding the miniature loop-like features reaches but is not exceeding 1.5 MK to 2 MK. On the one hand this distinguished them clearly from moss-type structures, and on the other hand shows that they cannot be energised by heat conduction from hotter loops emerging from the tiny features. Exploring several explanations, we conclude that the tiny coronal structures we see are miniature coronal loops spanning across one single granule, which would be consistent with observations and models of small-scale flux emergence in quiet Sun network regions. We thus suggest that miniature loop-like structures are primarily heated by the interaction of an emerging flux tube with the pre-existing field in the plage area.