Pison morosum is a solitary wasp of the family Crabronidae.

It is the only endemic species of Pison wasp to New Zealand.

Female specimens vary in length between 7.5 and 11.5 mm, and male specimens between 5.5 and 8.0 mm.

[2] It can be distinguished from Pison spinolae due to the lack of long erect hairs.

[2] Pison morosum is found throughout the mainland of New Zealand, as well as the Chatham Islands to the east.