This is one of the strangest colony types of all the ants that we have here. These ants use plant matter as compost for growing fungus to eat. The large bulbs seen in the cast are essentially underground farms for the ants. I don’t know that there actually is a common name for these locally, and before learning about them I would have thought their small colonies were just new fire ant colonies. Now that I have learned more about them, they’re easily identifiable by the crescent shaped mound of dirt they leave a few inches from the colony entrance.

The first attempt I made at casting one of these (several years ago), turned out great (Cast #036). I didn’t make a video of that casting so I tried a few more times while recording and realized it’s actually very difficult to get a full cast of these colonies due to the small tunnels (1/8 to 1/4 inch in diameter) and the large volume of the chambers. I’m trying to get a lot of aluminum into the large chambers through very small tunnels which are shrinking quickly from the hardening aluminum. The solution was to use an alloy of aluminum which stays molten longer and has lower viscosity.

From the ground surface, there were two colony openings. One of the tunnels splits into two just below the ground surface, leading three tunnels into the first small chamber. A single tunnel then leads down to the largest chamber. From this chamber, it appears there were two tunnels running to the lowest chamber; however, one appears to not have been fully cast.