The Corvan gilvos were a stick-like animal indigenous to the rainforests of Corvan II. Gilvos were uniquely suited to live in trees, as they closely resembled a tree branch. Their eating habits were similar to Earth's extinct Draco lizards. Their habitat was threatened by industrial pollutants on Corvan II, and by 2368, there were only fourteen gilvos in the wild.
That year, the USS Enterprise-D transported two gilvos to the protected planet of Brentalia. The gilvos were momentarily threatened by a fire that broke out aboard the ship during their transport in the biolab, but Commander William T. Riker was able to save the animals (at Alexander Rozhenko's insistence). (TNG: "New Ground")