ACTION COMICS 296 (January 1963)--"The Invasion of the Super-Ants" by Edmond Hamilton and Al Plastino:
Our story opens at the Municipal Zoo in a new wing devoted to insects, as Clark Kent tells Lois Lane a wealth of information about ants (for one and a half pages).
Not long after, a menace of giant ants creates a panic. As they have green Kryptonite, Superman is unable to get near them. When they kidnap Lois Lane, Superman flies through a cloud of red Kryptonite which bestows upon him temporary immunity to green K. and also an ant head.
His antennae enable him to telepathically communicate with the giant ant colony and they relate their strange story. They come from a world where human beings destroyed themselves in an atomic war and the ant population of that world were mutated by the radioactive fallout into advanced, giant ants.
They then embarked throughout the cosmos to take their message to every human civilization to stop atomic proliferation, so they won't end up like the humans of their world. As they came to Earth, their rocketship broke down and they had to make repairs. It happens that their ship uses green K. as its fuel.
Having heard their message of peace, Superman speaks before the United Nations, giving the ants' warning to all governments: "Avoid atomic war or the ant-head I grew will symbolize our Earth's future! If we can't live in peace, Man will vanish and the insects will inherit the Earth!"
In the 30th century, the Legion meet the ant-race of Canopus, which could be the same race of ants a thousands years in the future. It's another story from Edmond Hamilton (with John Forte art)--"The Return of Lightning Lad" in ADVENTURE COMICS 308 (May 1963). There's also the already mentioned tale "The Menace of Insect Island" in SUPERMAN'S PAL, JIMMY OLSEN 79 (September 1964).
And in SUPERBOY 124 (October 1965)--"The Insect Queen of Smallville" by Otto Binder and George Papp--Lana Lang comes to the assistance of an arthropoidal space traveller (from an unidentified world) who got trapped under a fallen tree near Smallville. When she frees the extraterrestrial, she's rewarded with a ring that has biogenetic powers to transform her into a new invertebrate each time she wills it. Thus begins her career as "Insect Queen" (which will one day win her honourary membership in the Legion of Super-Heroes).
As I'm sure Clark Kent would tell you (such a well-informed fellow), "Insect Queen" is a misnomer as Lana transforms into many other invertebrates that are not classified as insects.