Tetramorium scutum Hita Garcia & Fisher

Head longer than wide (CI 90–92); in full-face view posterior head margin weakly concave. Anterior clypeal margin with distinct median impression. Frontal carinae moderately to well developed, slightly diverging posteriorly, ending at or shortly before posterior head margin. Antennal scrobes weak to absent, shallow and without clear and distinct posterior and ventral margins. Antennal scapes short, not reaching posterior head margin (SI 71–74). Eyes moderate to relatively large (OI 24–25). Mesosomal outline in profile flat to weakly convex, comparatively low and long (LMI 38–39), moderately marginate from lateral to dorsal mesosoma; promesonotal suture absent; metanotal groove weak or absent. Propodeal spines moderate to long, elongate-triangular to spinose, and acute (PSLI 22–24); propodeal lobes elongate-triangular, always weakly shorter than propodeal spines, in profile spines and lobes strongly inclined towards each other. Petiolar node in profile high rounded nodiform to weakly squamiform, around 2.0 to 2.1 times higher than long (LPeI 48–50), anterior and posterior faces approximately parallel, anterodorsal and posterodorsal margins situated at about same height, petiolar dorsum relatively flat; node in dorsal view between 1.4 to 1.6 times wider than long (DPeI 144–154), in dorsal view pronotum between 2.2 to 2.5 times wider than petiolar node (PeNI 41–44). Postpetiole in profile subglobular, around 1.3 to 1.4 times higher than long (LPpI 70–74); in dorsal view around 1.3 to 1.4 times wider than long (DPpI 134–140), pronotum between 1.6 to 1.8 times wider than postpetiole (PpNI 57–62). Postpetiole in profile appearing slightly more voluminous than petiolar node, postpetiole in dorsal view around 1.3 to 1.4 times wider than petiolar node (PPI 133–142). Mandibles completely unsculptured, smooth, and shiny; clypeus weakly, irregularly, longitudinally rugulose with median area mostly unsculptured, smooth, and shiny, sometimes median rugula present, but then weakly developed and/or interrupted, one or two weak, irregular and broken rugulae present on each side; cephalic dorsum between frontal carinae longitudinally rugulose with six to nine rugae/rugulae, rugae/rugulae usually running from posterior clypeal margin to posterior head margin, often irregularly shaped, interrupted or with cross-meshes; scrobal area partly unsculptured and merging with surrounding sculpture; lateral head anteriorly reticulate-rugose to longitudinally rugose and posteriorly mostly unsculptured. Ground sculpture on head weakly to moderately reticulate-punctate, especially laterally. Dorsum of mesosoma irregularly longitudinally rugose; lateral mesosoma mostly irregularly longitudinally rugose with some reticulate-rugose elements. Ground sculpture on mesosoma weak to absent. Forecoxae unsculptured, smooth, and shining. Both waist segments and gaster fully unsculptured, smooth, and shining. Dorsum of head with several pairs of long, fine, standing hairs; mesosoma with six or more pairs from anterior pronotum to posterior mesonotum, propodeum without standing pilosity; petiole with one and postpetiole with one or two pairs of long, standing hairs; first gastral tergite with short, moderately dense, appressed pubescence in combination with several scattered, long, standing hairs. Anterior edges of antennal scapes and dorsal (outer) surfaces of hind tibiae with appressed hairs. Head, mesosoma, waist segments and gaster uniformly brown to dark brown contrasting with yellowish to light brown mandibles, antennae, and legs.

This new species is only known from the area around Ivohibe (Fig. 66) where it was collected from a few montane rainforest localities situated at elevations of 1200 to 1575 m. All specimens were sampled from leaf litter.