Maximum Spread of Invasive Fire Ants

After thinking about silly Mark Trail comic strips much more than I should, I thought I'd ask this forum about red imported fire ants (Solenopsis invicta). Fire ants originally came from South America, and they became a common pest in the United States. However, in our history, it took until the 1930s for the ants to begin their invasion of the southern U.S., and they spread to other countries such as Australia in later decades.

Could fire ant queens terrorize the world in an age of slow sea travel? If so, how far could they expand beyond their native habitats in the Amazon? Remember that fire ants can float on water in a sort of "raft" during floods.
 
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They've probably expanded to their maximum range in the US as of now (although climate change will gradually push them further north). They are (relatively) rare in places like much of Tennessee and Arkansas, and north of that even rarer, due to the fact winter is too cold for them. Before modern climate change when cold winters were more common, they'd be lucky to get that far. They would be a major headache in the Deep South if they were there earlier. They would have more time to solidify their infestations, though

The biggest potential for expansion is definitely outside the US (although IIRC all non-US occurences of invasive fire ants originated in the US). Most all of Australia but the driest parts and the mountainous parts make for good fire ant climate.

The worst place for them to expand to would be East Asia. That could impede development in China, India, the Philippines, etc.
 
Could fire ant queens terrorize the world in an age of slow sea travel? If so, how far could they expand beyond their native habitats in the Amazon? Remember that fire ants can float on water in a sort of "raft" during floods.
As someone who was stung by fireants frequently as a child, I wish there was a dislike button.
 
As someone who ended up getting stung so many times as a little kid that I ended up becoming dangerously close to allergic, they've already come too far.
 
For those who wonder about the inspiration for the topic, there was a storyline for Mark Trail where the characters were investigating an island near Hawaii infested with fire ants. After a series of misadventures, a volcano erupts and Mark & co. have to escape the island before it explodes, taking the ant colonies with it.
 
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