Classification of AT2017gmr/DLT17cq

We observed the candidate SN AT2017gmr, alias DLT 17cq (ATel #10706) on Sept. 6, 04.5UT, with the Isaac Newton Telescope on LaPalma, with the IDS spectrograph. The spectral range covers 3600-8000 Angstroms, with a resolution of 4A. The spectrum displays essentially a featureless blue continuum, with no signs of Balmer lines (neither in emission nor in absorption), and no Si lines either. There are hints of possible presence of broad line of FeII 4440, and possibly CaII 3950 also. This suggests that AT2017gmr is a young CC supernova, whose development will be monitored.