These things in packs can take down rexs, and carnos. Reason being because of there small hit box and high damage. And in packs they can melt many dinos.

Get one of each gender and breed a whole army

These little creatures are amazing for clearing caves just get about 20 of them drag them into a cave and watch them work you need to pay attention to there hp though there strength is in numbers so individuals can die

Best tame for the time and narcotics. I have about 20 of these above lvl 200 defend my base.. They shred people along with my turrets. I also raid with 10+ of them. They make shooting at me impossible as they swarm people not their mounts. Use the spyglass to scope dinos or people and whistle attack target. It is an invaluable sniper tool.
P.S. Keep them close to your fabricator and smithy to level faster.