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Florida Rosemary Big-headed Ants
Pheidole adrianoi
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Florida Rosemary Big-headed Ants·Section 1 of 8

Pheidole adrianoi Species Introduction

Founding strategy

Claustral. Single queen, sealed founding chamber, no outside food needed for the first generation. The main nuptial flights occur in July and August.

Natural history

Native to central and northern Florida, west to the panhandle, with records extending into Georgia and Alabama. A specialist of white-sand gaps in pine-oak forest and Florida scrub, where the nest entrance sits in a small crater of excavated sand and drops through a tunnel only 1 to 2mm wide to a main chamber 30 to 40cm down. Mature colonies stay small, around 60 majors and a few hundred minors. Both castes forage strictly by day, and unusually for the genus, the majors leave the nest and help carry food back. Most remarkable is the nest itself: colonies line their chambers with the black sclerotia of an ectomycorrhizal fungus associated with longleaf pine, and the sprouting mycelia bind the loose sand into stable walls.

What to expect as a keeper

Genuinely tiny and genuinely charming. Minor workers barely exceed 1mm and look like moving specks, while the majors reach about 2.5mm and are reddish brown against the much darker minors. Colonies stay small by Pheidole standards, so they will not outgrow a modest setup the way most of the genus does. Feed seeds first and insects second, and keep the barrier honest, because ants this small find any gap.