  We present analysis of 63 nearby ($<$ 44 Mpc) early-type galaxies hosting
nuclear star clusters using the recently discovered parameter Central Intensity
Ratio (CIR$_I$) determined from near-infra-red (3.6 $\mu$m) observations with
the Infra-red-array-camera of \emph{Spitzer} space telescope. The CIR$_I$, when
combined with filters involving age and $B-K$ colour of host galaxies, helps
identify two distinct classes of galaxies hosting nuclear star clusters. This
is independently verified using Gaussian Mixture Model. CIR shows a positive
trend with faint, low mass, and blue galaxies in the sample, while the opposite
is true for bright, high mass, and red galaxies, albeit with large scatter. The
variation of CIR$_I$ with central velocity dispersion, absolute B band
magnitude, dynamical mass, and stellar mass of host galaxies suggests that the
mass of nuclear star clusters increases with that of host galaxies, for faint,
low mass, young and blue galaxies in the sample. In bright, high-mass, old and
red galaxies, on the other hand, the evolution of nuclear star clusters appears
complex, with no apparent trends.The analysis also reveals that redder galaxies
($B-K > 3.76$) are more likely to be dominated by the central black-hole than
the nuclear star clusters, while for bluer galaxies ($B-K < 3.76$) in the
sample the situation is quite opposite.
