petiolar node
Petiolar node relatively quadrate

Petiolar node relatively quadrate and subpetiolar process broad in profile with a blunt anterior angle
Petiolar node tall and narrow

Petiolar node tall and narrow and the subpetiolar process narrow with a blunt posterior angle and lacking a distinct anterior angle
petiole evenly rounded

The petiolar node is evenly rounded, with the anterior and posterior faces both approximating similar curves. Used in Antkey to separate Tetramorium tonganum and Tetramorium lanuginosum from all other Tetramorium.
petiole square shaped

The petiolar node is square shaped, with discrete and nearly flat anterior, dorsal and posterior faces. Used in Antkey to separate Tetramorium bicarinatum, Tetramorium caldarium, Tetramorium caespitum_cf, Tetramorium simillimum and Tetramorium tsushimae from all other Tetramorium.
petiole wave shaped

The petiolar node consists of an anterior and dorsal face that are nearly fused into a single curve that reaches it highest point just before sharply cornering into the nearly flat posterior face. Used in Antkey to separate Tetramorium insolens and Tetramorium pacificum from all other Tetramorium species.
petiolar node and peduncle

petiolar node and peduncle (Tetramorium bicarinatum)
petiolar node wave-shaped

petiolar node wave-shaped (Tetramorium)
petiolar node square-shaped

petiolar node square-shaped (Tetramorium)
petiolar node evenly rounded

petiolar node evenly rounded (Tetramorium)