Is there a Greek equivalent of the Roman God Janus?
Apparently not. Some Di Indigetes (native Roman gods), such as Janus and Terminus, had no Greek equivalent and so retained an independent tradition; a few, like Bona Dea, did the same despite sharing attributes with a Greek figure (in this case Artemis). Others, like the twelve assistants of Ceres, became mere adjuncts to imported Greek deities (here Demeter).