  We present the brightest cluster galaxies (BCGs) catalog for SPectroscoic
IDentification of eROSITA Sources (SPIDERS) DR14 cluster program value-added
catalog. We list the 416 BCGs identified as part of this process, along with
their stellar mass, star formation rates, and morphological properties. We
identified the BCGs based on the available spectroscopic data from SPIDERS and
photometric data from SDSS. We computed stellar masses and SFRs of the BCGs on
the basis of SDSS, WISE, and GALEX photometry using spectral energy
distribution fitting. Morphological properties for all BCGs were derived by
Sersic profile fitting using the software package SIGMA in different optical
bands (g,r,i). We combined this catalog with the BCGs of galaxy groups and
clusters extracted from the deeper AEGIS, CDFS, COSMOS, XMM-CFHTLS, and XMM-XXL
surveys to study the stellar mass - halo mass relation using the largest sample
of X-ray groups and clusters known to date. This result suggests that the mass
growth of the central galaxy is controlled by the hierarchical mass growth of
the host halo. We find a strong correlation between the stellar mass of BCGs
and the mass of their host halos. This relation shows no evolution since z
$\sim$ 0.65. We measure a mean scatter of 0.21 and 0.25 for the stellar mass of
BCGs in a given halo mass at low ( $0.1<z < 0.3$ ) and high ( $0.3<z<0.65$ )
redshifts, respectively. We further demonstrate that the BCG mass is covariant
with the richness of the host halos in the very X-ray luminous systems. We also
find evidence that part of the scatter between X-ray luminosity and richness
can be reduced by considering stellar mass as an additional variable.
