Key to Tetramorium naganum-group species

This worker key is based on: [[Media:Hita Garcia, F. & Fisher, B.L. 2014. The hyper-diverse ant genus Tetramorium in the Malagasy region ‑ taxonomic revision of the T. naganum, T. plesiarum, T. schaufussii, and T. severini species.pdf|Hita Garcia, F. & Fisher, B.L. 2014. The hyper-diverse ant genus Tetramorium Mayr (Hymenoptera, Formicidae) in the Malagasy region ‑ taxonomic revision of the T. naganum, T. plesiarum, T. schaufussii, and T. severini species groups. ZooKeys 413, 1–170 (doi: 10.3897/zookeys.413.7172).]]

You may also be interested in:
 * Tetramorium naganum species group (species list, diagnosis, distribution, etc.)
 * Key to Malagasy Tetramorium species groups
 * Tetramorium

1

 * Propodeal spines relatively shorter (PSLI 25–27); waist segments without long standing hairs, instead with short, appressed to subdecumbent pubescence only, sometimes with one or two short erect to suberect hairs (Fig. 1A) [Madagascar] . . . . . Tetramorium dalek


 * Propodeal spines relatively longer (PSLI 27–37); waist segments always with long standing hairs and short appressed to subdecumbent pubescence (Fig. 1B) . . . . . 2

2
return to couplet #1
 * In profile petiolar node relatively thicker, around 1.5 to 1.6 times higher than long (LPeI 60–68) (Fig. 2A, B) . . . . . 3


 * In profile petiolar node relatively thinner, around 1.7 to 2.0 times higher than long (LPeI 50– 59) (Fig. 2C, D) . . . . . 4

3
return to couplet #2
 * First gastral tergite with moderately long, relatively scattered, appressed to decumbent pubescence in combination with several much longer, fine, and erect hairs (Fig. 3A) [Madagascar] . . . . . Tetramorium alperti


 * First gastral tergite with moderately short, abundant, subdecumbent to suberect pilosity, and without short, dense, appressed to decumbent pubescence or long, fine erect hairs (Fig. 3B) [Madagascar] . . . . . Tetramorium enkidu

4
return to couplet #2 [Madagascar]. . . . . Tetramorium gilgamesh
 * Eyes larger (OI 25–27); first gastral tergite covered by a mix of short to moderately long, abundant, decumbent to suberect pilosity, pilosity appearing disorganized due to varying degrees of inclination and hair length (Fig. 4A)

[Madagascar]. . . . . Tetramorium naganum
 * Eyes smaller (OI 21–23); first gastral tergite with short, dense, appressed to decumbent pubescence only, without any long, standing pilosity (Fig. 4B)