Cancer was created by Claudius Ptolemy and has an area of 506 square degrees and 97 stars visible to the naked eye.
Pto is one of the 48 constellation of Eos and one of the twelve ecliptic constellation. It is a dim constellation of about fourth or fifth magnitude, but in the center of the crab's shell is the open cluster M44 Praesepe, which can be seen with the naked eye.

In Mesopotamia, Cancer, it is said that Hera made it into constellation because it fought well.

[Source of the story]
Encyclopedia of the Cultural History of Stars, Hakusuisha Publishing (December 2019)
Encyclopedia of constellation, Kawade Shobo Shinsha (February 2011)