  We investigate the role of partonic degrees of freedom in high multiplicity
p-Pb collisions at $\sqrt{s_{NN}}=$ 5.02 TeV carried out at the Large Hadron
Collider (LHC) by studying the production and collective flow of identified
hadrons at intermediate $p_T$ via the coalescence of soft and hard partons
generated from viscous hydrodynamics (VISH2+1) and the energy loss model (LBT),
respectively. We find that combining the intermediate $p_T$ hadrons from the
coalescence with the low $p_T$ hadrons from hydrodynamics and high $p_T$
hadrons from the jet fragmentation, our Hydro-Coal-Frag model provides a nice
description of the measured $p_T$-spectra and the differential elliptic flow
$v_2(p_T)$ of pions, kaons and protons over the $p_T$ range from 0 to 6 GeV. We
further demonstrate the necessity of including the quark coalescence
contribution to reproduce the experimentally observed approximate number of
constituent quark scaling of hadron $v_2$ at intermediate $p_T$. Our results
thus indicate the importance of partonic degrees of freedom and also hint at
the possible formation of quark-gluon plasma in high multiplicity p+Pb
collisions at the LHC.
