1) Greek god 
[genus] Zelus is a genus of assassin bug family (Reduviidae), in the subfamily Harpactorinae. There are currently 60 described species, most of which are found in Central and South America. Five species are present in North America. Some species have been investigated for their potential as biocontrol agents in integrated pest management. Z...
In Greek mythology, Zelus was son of the Titan Pallas and Styx. He was a constant companion of Zeus and personified zeal.