Shiva panchayatan is when five dieties are all worshipped together. Commonly a puja is done for one diety at one time. This is an exceptional case where five dieties are all worshipped together. In this case Shiva, Parvati, Ganesha, Nandi and Kartik. But in this particular poster Kartik seems to be missing. While there are two identical persons on both sides blowing a conch. They seem attendants or ganas. Maybe the lion is the one representing Kartik. Kartik is fiery, so lion does fit the bill.
A digital reprint of this century old poster can be ordered on paper, canvas and framed canvas. I promise a very good quality print on A4 and a decent one on A3.