Make ants one day in advance. For each treat, knead 1/2 teaspoon Gum-Tex into 6 oz. fondant. Tint black.
Roll three fondant balls, each 1/2 in. dia. Flatten slightly and shape to form body sections. Use brush and piping gel to attach sections.
For legs, roll three logs, each 1/16 in. dia. x 1 in. long. Use brush and piping get to attach legs to body. Let dry overnight on cornstarch-dusted cake board.