Context : The morphology and stellar populations of low-luminosity early-type galaxies in clusters have until now been limited to a few relatively nearby clusters such as Virgo or Fornax .
Scenarii for the formation and evolution of dwarf galaxies in clusters are therefore not well constrained .

Aims : We investigate here the morphology and stellar populations of low-luminosity galaxies in the relaxed richness class 1 cluster Abell 496 ( z = 0.0330 ) .

Methods : Deep multiband imaging obtained with the CFHT Megacam allowed us to select a sample of faint galaxies , defined here as objects with magnitudes 18 < r ^ { \prime } < 22 mag within a 1.2 arcsec fibre ( -18.8 < M _ { B } < -15.1 mag ) .
We observed 118 galaxies spectroscopically with the ESO VLT FLAMES/Giraffe spectrograph with a resolving power R = 6300 .
We present structural analysis and colour maps for the 48 galaxies belonging to the cluster .
We fit the spectra of 46 objects with PEGASE.HR synthetic spectra to estimate the ages , metallicities , and velocity dispersions .
We estimated possible biases by similarly analysing spectra of \sim 1200 early-type galaxies from the Sloan Digital Sky Survey Data Release 6 ( SDSS DR6 ) .
We computed values of \alpha /Fe abundance ratios from the measurements of Lick indices .
We briefly discuss effects of the fixed aperture size on the measurements .

Results : For the first time , high-precision estimates of stellar population properties have been obtained for a large sample of faint galaxies in a cluster , allowing for the extension of relations between stellar populations and internal kinematics to the low-velocity dispersion regime .
We have revealed a peculiar population of elliptical galaxies in the core of the cluster , resembling massive early-type galaxies by their stellar population properties and velocity dispersions , but having luminosities of about 2 magnitudes fainter .

Conclusions : External mechanisms of gas removal ( ram pressure stripping and gravitational harassment ) are more likely to have occurred than internal mechanisms such as supernova-driven winds .
The violent tidal stripping of intermediate-luminosity , early-type galaxies in the cluster core can explain the properties of the peculiar elliptical galaxies surrounding the cD galaxy .