What was the serpent of Gen 3:1?

A critic might first insist on exploring the plausibility of a talking snake, but in fact before confronting the critic we must clarify what exactly is going on here. The real issue here is: considering that this apparent snake could speak and indeed tempt Eve so as to precipitate the disastrous Fall, how was that possible, considering that snakes cannot speak? Was it a real, then-ordinary snake, albeit one with legs or wings, since it was later cursed to go on its belly? Or was it, as a popular theory has it, Satan in the form of a snake? Josephus even suggests (groundlessly) that all animals before the Fall could talk, so that this was a then-ordinary snake. Now, we already know from much else in the Bible that God permits Satan to test us, as he tested Job and Jesus, and surely we would expect none less than Satan to be the cause of our downfall. Moreover, John identifies “that old serpent, called the Devil, and Satan, which deceiveth the whole world” (Rev. 12:9); so we had better say the same, i.e., that the serpent in the Garden was Satan appearing in the body, or perhaps only the apparent form, of a snake.