Stout bodied, easily recognized by their characteristic antennae: three-segmented, the third segment very long; males of some species have the last antennal segment U-shaped or Y-shaped. Most argids are black or dark colored.
NA argid larvae may be separated from other sawfly larvae by the following combination of characters: (1) Presence of a divergent lobe next to the tarsal claw of each thoracic leg (lobe reduced in Atomacera
); (2) one-segmented antenna which may be flat, rounded, or peglike; (3) abdominal segments 1 to 9 each with 3, sometimes 2, annulets; (4) presence of a tarsal claw on each thoracic leg, or only prothoracic leg lacking a tarsal claw.(3)