history of - First non humanoid intelligent alien depiction in literature?

In an unrelated question, I was thinking of the Horta (ST:TOS, Devil in the Dark), which to paraphrase McCoy in one of the books looks like "an ambulatory pepperoni pizza, extra cheese".

Given that human looking intelligent aliens are so common as to be a trope, what is the earliest depiction in Literature of an intelligent alien life form as being non humanoid in appearance? (i.e. radically different such as the Horta)

Edit: For non humanoid, I would intend it to be readily distinguishable from the typical two armed/two legged alien depiction. For example, all the members of the Max Rebo band would qualify (two arms, two legs, odd heads but still humanoid). Jabba the Hutt would not qualify as humanoid.

Answer

True History by Lucian of Samosata is officially known as the oldest depiction of alien creatures in literature, dating from second century AD.

In True Stories, Lucian and a company of adventuring heroes sail westward through the Pillars of Hercules (the Strait of Gibraltar) in order to explore lands and inhabitants beyond the Ocean, are blown off course by a strong wind, and after 79 days come to an island. This island is home to a river of wine filled with fish and bears, a marker indicating that Heracles and Dionysus have traveled to this point, along with normal footprints and giant footprints.

Shortly after leaving the island, they are lifted up by a whirlwind and after seven days deposited on the Moon. There they find themselves embroiled in a full-scale war between the king of the Moon and the king of the Sun over colonisation of the Morning Star, involving armies including such exotica as stalk-and-mushroom men, acorn-dogs ("dog-faced men fighting on winged acorns"), and cloud-centaurs. Unusually, the Sun, Moon, stars and planets are portrayed as locales, each with its unique geographic details and inhabitants. The war is finally won by the Sun's armies clouding the Moon over. Details of the Moon follow; there are no women, and children grow inside the calves of men.

I'd say "cloud centaurs" qualify as one of the weirdest alien creatures in history... and it was the first!