Where is the kakliosaur specimen/fossil?

A salarian in the Presidium Commons of the Citadel asked me to hunt down a kakliosaur specimen for him. Where do I need to go and what am I looking for in order get him what he wants?

2 Answers

The specimen is on the planet Intai'sei in the Phoenix system in the Argos Rho cluster. Just scan that planet and you'll get the specimen. After scanning return to the salarian on the Citadel and talk to him to finish the mission.

This system is only accessible after a certain mission:

Priority: Geth Dreadnaught

See also the entry for this mission on the ME3 Wikia

You need to scan the planet Intai'sei. It's in Argos Rho, in the Phoenix system. You should obtain it as soon as you scan the planet.