Key to Tetramorium tortuosum-group species

Based on Hita Garcia and Fisher (2012. The ant genus Tetramorium Mayr (Hymenoptera: Formicidae) in the Malagasy region - taxonomic revision of the T. kelleri and T. tortuosum species groups. Zootaxa. 3592:1-85. [[Media:Hita Garcia & Fisher 2012b.pdf|PDF ]])

1

 * In profile forecoxae completely covered with very distinct, strong, longitudinal rugae (T. smaug species complex) (Fig. 11) . . . . . 2


 * In profile forecoxae without very distinct, strong, longitudinal rugae; usually unsculptured, smooth and shining, but often with traces of rugulae or punctate sculpture (Figs. 12, 13) . . . . . 9

2
return to couplet #1


 * Propodeal spines long to extremely long (PSLI 34 - 50, generally below 45); comparatively hairy species with numerous long standing hairs on the first gastral tergite (Fig. 14) . . . . . 3


 * Propodeal spines always extremely long (PSLI 48 - 72; generally above 50); less hairy species with no or few scattered, long standing hairs (Figs. 15, 16) . . . . . 7

3
return to couplet #2


 * Petiolar node with posterodorsal margin situated higher than anterodorsal, dorsum convex (Fig. 17) . . . . . Tetramorium adamsi


 * Petiolar node with anterodorsal and posterodorsal margins at about the same height, dorsum flat to weakly convex (Fig. 18) . . . . . 4

4
return to couplet #3


 * Antennal scapes comparatively long (SI 89 - 92); petiolar node higher (LPeI 81 - 88); body colour dark brown to black (Figs. 19, 20) . . . . . Tetramorium nazgul


 * Antennal scapes shorter than above (SI 79 - 85); petiolar node lower (LPeI 89 - 97); body colour orange to light brown (Figs. 21, 22) . . . . . Tetramorium marojejy

7
return to couplet #2


 * First gastral tergite without any standing hairs, only with moderately dense appressed pubescence (Fig. 23) . . . . . Tetramorium latreillei


 * First gastral tergite with several standing hairs and scarce pubescence (Fig. 24) . . . . . 8

8
return to couplet #7


 * Leading edges of antennal scapes with appressed hairs; mesosoma with just one to two pairs of standing hairs on the pronotal dorsum (Figs. 25, 26) . . . . . Tetramorium sabatra


 * Leading edges of antennal scapes with subdecumbent to suberect hairs; mesosoma with 7 to 14 pairs of standing hairs throughout the whole mesosomal dorsum (Figs. 27, 28) . . . . . Tetramorium smaug

9
return to couplet #1


 * First gastral tergite with either reticulate-punctate or costulate sculpture (Figs. 29, 30) . . . . . 10


 * First gastral tergite unsculptured, smooth, and shining (T. andrei species complex) (Fig. 31) . . . . . 16

10
return to couplet #9


 * First gastral tergite with basigastral costulae (T. noeli species complex) (Fig. 32) . . . . . 11


 * First gastral tergite differently sculptured (T. jedi species complex) (Fig. 33) . . . . . 14

11
return to couplet #10


 * In profile view, petiolar node with anterodorsal and posterodorsal margins at about the same height, and the dorsum flat to weakly convex (Fig. 34) . . . . . 12


 * In profile view, petiolar node with the posterodorsal margin situated higher than the anterodorsal margin, and the dorsum convex (Fig. 35) . . . . . 13

12
return to couplet #11


 * Eyes comparatively moderate to large (OI 22 - 24); propodeal spines comparatively long (PSLI 41 - 45) (Figs. 36, 37) . . . . . Tetramorium aherni


 * Eyes comparatively small (OI 16 - 17); propodeal spines comparatively short (PSLI 27 - 29) (Figs. 38, 39) . . . . . Tetramorium singletonae

13
return to couplet #11


 * Head distinctly longer than wide (CI 92 - 95); propodeal spines extremely long but comparatively shorter than below (PSLI 38 - 48); postpetiole relatively higher (LPpI 68 - 72) and broader (DPpI 119 - 129) (Figs. 40, 41) . . . . . Tetramorium noeli


 * Head weakly longer than wide (CI 97 - 98); propodeal spines extremely long but comparatively longer than above (PSLI 60 - 65); postpetiole relatively lower (LPpI 77 - 81) and narrower (DPpI 104 - 112) (Figs. 42, 43) . . . . . Tetramorium ambanizana

14
return to couplet #10


 * Petiolar node in dorsal view distinctly longer than wide (DPeI 79 - 85), in profile anterodorsal and posterodorsal margins at about same height; first gastral tergite completely covered with distinct reticulate-punctate sculpture (Figs. 44, 45) . . . . . Tetramorium jedi


 * Petiolar node in dorsal view distinctly wider than long (DPeI 111 - 137); in profile anterodorsal margin situated higher than posterodorsal margin and dorsum tapering backwards; first gastral tergite never completely covered with distinct reticulate-punctate sculpture, generally with superficial reticulate-punctate sculpture restricted to the basal first half of the tergite (Figs. 46, 47) . . . . . 15

15
return to couplet #14


 * Propodeal spines very long (PSLI 37 - 44); petiolar node relatively lower (LPeI 63 - 73) and narrower (DPeI 111 - 118); petiolar dorsum strongly rugose (Fig. 48) . . . . . Tetramorium pleganon


 * Propodeal spines long, but shorter than above (PSLI 27 - 37, usually below 34); petiolar node relatively higher (LPeI 54 - 66) and broader (DPeI 126 - 137); petiolar dorsum weakly rugose (Fig. 49) . . . . . Tetramorium avaratra

16
return to couplet #9


 * Posterodorsal corner of petiolar node strongly protruding posteriorly (Fig. 50) . . . . . Tetramorium andohahela


 * Posterodorsal corner of petiolar node not protruding posteriorly (Fig. 51) . . . . . 17

17
return to couplet #16


 * Eyes very small (OI 15 - 16); propodeal spines long (PSLI 28 - 33); anterodorsal margin of petiolar node situated slightly higher than posterodorsal margin; body orange to light reddish brown in colour (Fig. 52) . . . . . Tetramorium isectum


 * Character combination never as above; if eyes small, then propodeal spines very long to extremely long (Figs. 53, 54) . . . . . 18

18
return to couplet #17


 * Petiolar node in profile comparatively high, between 1.3 to 1.6 times higher than long (LPeI 64 - 74); propodeal lobes strongly reduced and inconspicuous (Fig. 55) . . . . . Tetramorium electrum


 * Petiolar node in profile less high than above, between 1.1 times longer than high to 1.3 times higher than long (LPeI 76 - 105); propodeal lobes variably developed, usually conspicuous (Figs. 56, 57) . . . . . 19

19
return to couplet #18


 * Propodeal spines extremely long (PSLI 58 - 64) (Figs. 58, 59) . . . . . 20


 * Propodeal spines long to very long, but always significantly much shorter than above (PSLI 29 - 45) (Figs. 60, 61) . . . . . 21

20
return to couplet #19


 * Mandibles unsculptured, smooth, and shining; body colour yellow (Figs. 62, 63) . . . . . Tetramorium elf


 * Mandibles noticeably longitudinally sculptured; body colour very dark brown to black (Fig. 64, 65) . . . . . Tetramorium isoelectrum

21
return to couplet #19


 * Petiolar node in dorsal view relatively long, always more than 1.3 times longer than wide (DPeI 72 - 76) (Fig. 66) . . . . . Tetramorium ala


 * Petiolar node in dorsal view relatively wider, always between 1.0 to approximately 1.2 times longer than wide (DPeI 82 - 98) (Figs. 67, 68) . . . . . 22

22
return to couplet #21


 * Eyes relatively small (OI 16 - 17); propodeal spines relatively short (PSLI 29 - 30) (Fig. 69) . . . . . Tetramorium nify


 * Eyes always much larger (OI 19 - 25); propodeal spines relatively longer (PSLI 32 - 45) (Figs. 70, 71) . . . . . 23

23
return to couplet #22


 * Petiolar node with weakly defined and fairly rounded anterodorsal and posterodorsal margins; postpetiole relatively longer, longer than wide to slightly wider than long (DPpI 95 - 101) (Fig. 72) . . . . . Tetramorium voasary


 * Petiolar node with moderately to sharply defined anterodorsal and posterodorsal margins; postpetiole relatively wider, between 1.0 to 1.4 times wider than long (DPpI 103 - 136) (Fig. 73, 74) . . . . . Tetramorium andrei