Key to Tetramorium tortuosum-group species of the New World
This worker key is modified from Vásquez-Bolaños et al. 2011. It does not include Tetramorium azcatltontlium.
You may also be interested in:
- The Tetramorium tortuosum species group
- Key to Tetramorium species of the United States
- Checklist of Tetramorium species of United States
- Checklist of Tetramorium species of Mexico
- Tetramorium
1
- Hairs length of antennal scape and external surface of metatibia distinctly longer than maximal diameter of corresponding appendage. Scape Index (SI) 94-99 (Mexico: Jalisco and Nayarit) . . . . . Tetramorium mexicanum
- Hairs length of antennal scape and external surface of metatibia distinctly shorter than maximal diameter of corresponding appendage. Scape Index (SI) 79-90 . . . . . 2
2
return to couplet #1
- Petiolar dorsal surface without sculpture. Small ants, range of head width (HW range 0.66-0.72 mm; Mexico: Jalisco and Nayarit) . . . . . Tetramorium placidum
- Petiolar dorsal surface with sculpture. Large ants, head width (HW) between 0.77 mm and 1.0 mm . . . . . 3
3
return to couplet #2
- Large eyes, maximal diameter greater than a quarter of the head width. Hairs length on pronotal dorsal surface and frontal carinae, shorter than maximal eye diameter; small and erected hairs (USA: Arizona and Texas) . . . . . Tetramorium hispidum
- Small eyes, maximal diameter less than a quarter of the head width. Hairs length on pronotal dorsal surface and frontal carinae equal or greater than maximal eye diameter; longer hairs, fine and curved . . . . . 4
4
return to couplet #3
- Dorsum of body with longitudinal ridges (Mexico: Baja California, Coahuila, Durango, Hidalgo, Jalisco, Michoacán, Nayarit, Nuevo Leon, Puebla, San Luis Potosí, Sonora, Tamaulipas and Zacatecas) . . . . . Tetramorium spinosum
- Dorsum of body reticulated . . . . . 5
5
return to couplet #4
- Postpetiole dorsum without ridges. Total length from 3.4 mm to 3.8 mm (Mexico: Jalisco) . . . . . Tetramorium bicolorum
- Postpetiole dorsum with ridges. Total length from 3.8 mm to 4.0 mm (Mexico: Puebla) . . . . . Tetramorium notomelanum