Brief history lesson incoming. (Don't worry, the characters have great names and there's a crazy twist at the end!)
The Maserati Tipo 151/3 was designed by the same man as the famous Ferrari Breadvan, Pierre Drogo, according to the Kamm aerodynamic theory for Le Mans in 1964. The Kamm theory, named after Wunibald Kamm (I told you there would be great names. I mean, Wunibald. How cool is that?) basically says that the best way to make a vehicle aerodynamic is to make the lines of the body flow smoothly straight back and then cut off abruptly at the tail. Hence the "Kammback" bodystyle seen on other cars since then including, of all things, the Toyota Prius.
See the resemblance?