Well, I have found this much previously. It refers to the aftermath of Achilles being found in King Lycomedes' court disguised as a woman.
"Once discovered, Achilles eagerly joined the army, because he preferred a short but glorious life than a long but oblivious life of a farmer. Achilles returned to his father's kingdom, Phthia (southern Thessaly), where he received warriors and fifty ships, from his father. The warriors were the legendary Myrmidons, originally from the island of Aegina."
And about Aegina...
"Aegina was the island located in the Saronic Gulf, east of the coast of Argolis. Aegina was originally called Oenone or Oenopia... Aeacus became king of the island Aegina..."
And of the Myrmidon origins...
"Hera sent a pestilence that killed entire population. Aeacus prayed to his father (Zeus) to repopulate the island. Zeus answered his son's prayer, by transforming the boundless ants into humans. These people became known as the Myrmidons..."
An alternate origin tale...
"A different tradition says that the Myrmidons had no such remarkable beginning, but were descendants of Myrmidon, a Thessalian nobleman. Myrmidon married Peisidice, the daughter of Aeolus, king of Thessaly. Myrmidon was the father of Actor and Antiphus."
Actor (or his decendant) became the king of Phthia, the same kingdom later ruled by Achilles' father. If this second origin story is true, then the Myrmidons existed for several generations before the Trojan war began, and Achilles did not lead elite mercenaries in the war (as often claimed), but actually commanded a group of his kinsmen.
Those quotes come from...
http://www.timelessmyths.com/classical/trojanwar.html
An excellent site with some very well-thought analysis. It also has one of the more complete lists of gods and dynasties, including family trees (divine and mortal).
It also appears that the Myrmidons were armored in black panoply, probably a transitional type somewhere betwen the Dendra style and the more mobile Bell style. Such armor stained black would certainly give a strongly carpace-like apperance, lending to the ant-men myth.
Hope that helps.