1 Introduction  
2 Near-infrared and optical imaging  
2.1 $J H K_{\mathrm{s}}$ CAIN-II/Telescopio Carlos Sánchez  
2.2 $I$ CCD/Telescopio IAC-80  
3 Analysis  
3.1 Known objects in the survey area  
3.2 X-ray HRC $^+$ ACIS/ Chandra Space Telescope  
3.3 Selection of candidate cluster members  
4 Results and discussion  
4.1 New low-mass cluster members  
4.2 $K_{\mathrm{s}}$ excesses, X rays and discs  
4.3 Spatial density  
4.4 Additional remarkable objects  
5 Conclusions