Heptapod

Heptapods are an intelligent, space-faring extraterrestrial species in Story of Your Life and the 2016 film Arrival. In both works, their first contact with humans and Dr. Louise Bank's struggle to communicate with them serve as the plot and are used to explore themes about determinism, language and the Sapir-Whorf hypothesis.

Biology
As the name suggests, a heptapod has seven limbs, whose arrangement makes the creature heptaradially-symmetrical.