and on the same webpage, I think we have our winner, since Yellow Peri seems more like a Bat-mite/Mxy/Bizarro type pest.
Yggadris
First Appearance: Mystery In Space #60 (June 1960)
Yggardis is a sentient, tentacled planet that scours other worlds for life forms to populate it -- which die within 24 hours of the transplantation. Originally thwarted by Adam Strange, Yggardis later joined (on a long-distance-basis) the Enchantress' team of Forgotten Villains, who battled the Forgotten Heroes and Superman.
I finally picked up the Forgotten Heroes/Forgotten Villains issues of DC COMICS PRESENTS and am shocked to find no entry on this list for Yggadris, The Living Planet. Somebody who knows the DCU better than me can maybe do an entry on this, er, being -- I'm assuming if he was a Forgotten Villain this wasn't his first appearance.
I checked my trusty WHOS WHO, but the only mention of Yggardis is in the Forgotten Villains entry. He is listed as a sorcerer who, along with Krakow, an 18th century Polish mystic, and the Enchantress, were the focus of the Forgotten Villains plans in their appearance in DC COMICS PRESENTS #77-78.