From Star Wars - Episode II: Attack of the Clones, the Acklay was one of the three creatures used by the geonosians, to attack Anakin, Padme and Obi-Wan. The Acklay was the largest and most deadly of the three monsters. After the Jedi arrived, the Acklay went awol and started to attack and dismembered battle droids, geonosian's and Jedi alike. It managed to sneak up Upon Obi-Wan and two battle droids before having its legs wounded by Obi-Wan's light saber and being put out of its misery with a final and fatal blow to the head.
It resembles a giant mantis with sharp stake teeth.