Martians are a squid-looking race that populates Mars. They appear in Go! Go! Ackman by Akira Toriyama, and make a cameo in the Dragon Ball manga and Jaco the Galactic Patrolman.
Overview
Go! Go! Ackman
In Go! Go! Ackman, two Martians come to Earth in order to annihilate the Earthlings. Ackman tries to join them, but one Martian attacks him with his Martian Punch. Mad, Ackman rush towards one of them and cuts him in half with his sword. The other Martian fires his Martian Flash at Ackman, but Ackman dodges the attack and kills the alien with a kick to the face.
Dragon Ball Z
In the Dragon Ball manga, a Martian is shown in the Other World when Goku telepathically comunicates with his family thanks to King Kai.
Jaco the Galactic Patrolman
A Martian is shown in the third chapter of Jaco the Galactic Patrolman, when Jaco has a flashback showing the Galactic Police.