Formica trigona

Radchenko et al. (2021) question the placement of this taxon within the genus Formica. They note that F. trigona is too small for Formica (ca. 2.5 mm) with a triangular head (“Caput trigonium”) and long antennae (“antennae longitudine capitis et thoracis”). These features raise doubts that this species should even be included to the family Formicidae.

Distribution
This taxon was described from.

Nomenclature

 * † trigona. †Formica trigona Presl, 1822: 198 (no caste given) BALTIC AMBER (Eocene).