Tetramorium malagasy

Widely distributed in Madagascar, and seems to prefer deciduous forest habitats, such as tropical dry forest, gallery forest, spiny forest or thicket, whereas it is much rarer in humid forests. It occurs in many localities at the western coast from the Mahafaly Plateau north to Namoroka, and several more in the southwest from Beza-Mahafaly through Sakaraha and Zombitse to Vohibasia, Analalava, and Isalo. Tetramorium malagasy is also present in the southeast around Mahavelo and Berenty, and several forests in the east north to Moramanga. However, it seems to be comparatively rare north of Moramanga in the east and Namoroka in the west since it was only sampled from three localities in the northwest (Anabohazo, Ambilanivy, Ambato). (Hita Garcia and Fisher 2012)

Identification
A member of the Tetramorium bessonii-species group

The following combination of characters distinguishes T. malagasy from the other species group members: short antennal scapes (SI 71 - 74); PSLI 33 - 37; absence of promesonotal suture; petiolar node in profile high nodiform, anterior and posterior faces approximately parallel, anterodorsal and posterodorsal angles at about same height, dorsum well-developed and not tapering backwards posteriorly; standing hairs absent from waist segments and first gastral tergite; and pubescence on first gastral tergite very short and appressed. (Hita Garcia and Fisher 2012)

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  malagasy. Tetramorium malagasy Hita Garcia & Fisher, 2012: 18, figs. 2, 8, 9, 17-19 (w.) MADAGASCAR.

Worker
HL 0.76 - 0.85 (0.82); HW 0.76 - 0.87 (0.82); SL 0.56 - 0.62 (0.60); EL 0.16 - 0.20 (0.18); PH 0.43 - 0.49 (0.46); PW 0.56 - 0.63 (0.60); WL 1.01 - 1.13 (1.07); PSL 0.25 - 0.31 (0.28); PTL 0.17 - 0.20 (0.19); PTH 0.31 - 0.34 (0.33); PTW 0.27 - 0.32 (0.29); PPL 0.22 - 0.25 (0.24); PPH 0.30 - 0.36 (0.33); PPW 0.32 - 0.37 (0.35); CI 100 - 102 (101); SI 71 - 74 (73); OI 20 - 24 (22); DMI 54 - 58 (56); LMI 42 - 45 (43); PSLI 33 - 37 (34); PeNI 45 - 51 (48); LPeI 51 - 63 (57); DPeI 147 - 165 (155); PpNI 52 - 61 (57); LPpI 68 - 75 (72); DPpI 138 - 152 (145); PPI 112 - 129 (120) (15 measured).

Head generally wider than long (CI 100 - 102). Anterior clypeal margin with distinct median impression. Frontal carinae well-developed, becoming weaker shortly after level of posterior eye margin and fading out shortly before posterior head margin. Antennal scrobes faint to absent, posterior and ventral margins never differentiated. Antennal scapes short, not reaching posterior head margin (SI 71 - 74). Eyes small to moderate (OI 20 - 24). Mesosomal outline in profile convex, dorsally transversely rounded, weakly to moderately marginate from lateral to dorsal mesosoma; promesonotal suture absent, metanotal groove weak but present; mesosoma comparatively stout (LMI 42 - 45). Propodeal spines long, spinose, and acute (PSLI 33 - 37). Propodeal lobes very small and broadly triangular. Petiolar node high nodiform, anterior and posterior faces approximately parallel, anterodorsal and posterodorsal angles at about same height, dorsum not tapering backwards posteriorly; node in dorsal view not strongly transverse, between 1.4 to 1.7 times wider than long (DPeI 147 - 165), in lateral view between 1.6 to 2 times higher than long (LPeI 51 - 63). Postpetiole in profile rounded and weakly anteroposteriorly compressed, approximately 1.3 to 1.5 times higher than long (LPpI 68 - 75), in dorsal view between 1.3 to 1.6 wider than long (DPpI 138 - 152). Postpetiole in profile less voluminous than petiolar node, in dorsal view approximately 1.1 to 1.3 times wider than petiolar node (PPI 112 - 129). Mandibles distinctly longitudinally striate; clypeus always with strong median longitudinal ruga and one or two weaker rugulae at each side; cephalic dorsum between frontal carinae only with one well-developed longitudinal median ruga, median ruga diverging approximately at eye level into two rugae running to posterior clypeal margin, area between median ruga and frontal carinae often unsculptured or with traces of weak rugulae, median ruga of same length as frontal carinae; scrobal area, lateral and ventral head with irregular longitudinal rugulae, anteriorly more reticulate-rugose and posteriorly more weakly developed. Ground sculpture generally weak, but present. Mesosoma, waist segments, and gaster unsculptured and smooth. Ground sculpture on whole body generally faint. Head with several long, standing hairs, mesosoma often without any pilosity, mesonotum sometimes with one pair of hairs, waist segments and first gastral tergite always without any standing hairs; whole body with widely spaced short, appressed pubescence. Whole body of uniform brownish colour.

Type Material
Holotype worker, MADAGASCAR, Toliara, Forêt de Mite, 20.7 km 29° WNW Tongobory, 23.52417 S, 44.12133 E, 75 m, gallery forest, ex rotten log, BLF5905, 27.II.-3.III.2002 (B.L. Fisher et al.) (: CASENT0449550). Paratypes, eight workers with same data as holotype (: CASENT0449549; CASC: CASENT0449540; CASENT0449541; CASENT0449542; CASENT0449543; CASENT0449544; CASENT0449545; CASENT0449547; CASENT0449548); 27 workers with same data as holotype but collection code BLF5850 (CASC: CASENT0018397; CASENT0018732; CASENT0018738; CASENT0018740; CASENT0018748; CASENT0019010; CASENT0019013; CASENT0019016; CASENT0019018; CASENT0019024;CASENT0019027; CASENT0019028; CASENT0019031; CASENT0019036; CASENT0019038; CASENT0019051;CASENT0019040; CASENT0019044; CASENT0019053; CASENT0019056; CASENT0019057; CASENT0019061; CASENT0019064; CASENT0019066; CASENT0019076; MCZ: CASENT0018734; NHMB: CASENT0018736); and four workers with same data as holotype but collection code BLF5961 (CASC: CASENT0004095; CASENT0004098; CASENT0004104; : CASENT0004141).

Etymology
The new species is dedicated to Madagascar, its people and language. The species epithet is a noun in apposition and thus invariant.

References based on Global Ant Biodiversity Informatics

 * Garcia H. F. and B. L. Fisher. 2012. The ant genus Tetramorium Mayr (Hymenoptera: Formicidae) in the Malagasy regiontaxonomy of the T. bessonii, T. bonibony, T. dysalum, T. marginatum, T. tsingy, and T. weitzeckeri species groups. Zootaxa 3365: 1-123
 * Ravelomanana A., and B. L. Fisher. 2013. Diversity of ants in burned and unburned grassland, and dry deciduous forest in the Beanka Reserve, Melaky Region, western Madagascar. Malagasy Nature 7: 171-183.