Arcantiodelphys marchandi improves our knowledge of the earliest stages of the marsupial history, so far known mostly from North American fossils. Its main significance is that the beginning of the marsupial history also involved Europe. Furthermore, it confirms faunal links between North America and Europe during the mid-Cretaceous.
It is from these primitive marsupials from the “Euramerican“ Cretaceous that the modern marsupials colonized the southern landmasses, South America and mainly Australia where they are nowadays well diversified. Opossums and kangaroos are extant representatives of this very old northern origin of the marsupials.