Eoformica pinguis

Introduction

Eoformica pinguis is an extinct ant species from the Eocene epoch, living approximately 50 million years ago. It is known from exceptional fossil impressions in the Green River Formation of the western United States (Colorado, Montana, Utah, and Wyoming) as well as the Kishenehn Formation . This species is one of the most abundant ant fossils ever discovered, comprising about 40% of all ant impressions in the Green River deposit . Males measured 6.00–6.85 mm in body length (average 6.35 mm), and females were slightly larger at 7.3–7.5 mm . The genus Eoformica cannot be reliably placed in any modern subfamily – it likely belongs to either Dolichoderinae or Formicinae, but intact wing fossils needed for definitive classification have never been found .