[1] The typical size for a worker is around 10–15.5 millimetres long.

The species is black mostly, with the exceptions where the mandibles, antennae and legs are dark brown.

They have similarities to some Myrmecia species as they do not have teeth, which most of its kind contain.

[2][3][4] Myrmecia piliventris has a genome similar to that of the jack jumper ant.

However its chromosome complement is n=2, higher than the jack jumper ant, but most of its relatives of the genus Myrmecia have a much higher chromosome count.