Nesomyrmex hafahafa

This species is widely distributed along the western forests of Madagascar between the 23rd and 20th southern latitudes.

Identification
A member of the hafahafa species-group. The three pairs of dorsal spines (pronotal spines, propodeal spines and antero-dorsal spines on petiolar node) makes the appearance of this group extremely unique; no similar species group has been found either in the Malagasy region or on the African continent.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  hafahafa. Nesomyrmex hafahafa Csösz & Fisher, 2015: 49, figs. 22-24 (w.q.m.) MADAGASCAR.

Worker
Body color: yellow; brown. Body color pattern: body concolorous, only clava darker. Absolute cephalic size: 1062 [974, 1142] μm (n = 48). Cephalic length vs. maximum width of head capsule (CL/CWb): 1.224 [1.193- 1.254]. Postocular distance vs. cephalic length (PoOc/CL): 0.388 [0.361, 0.406]. Postocular sides of cranium contour frontal view orientation: converging posteriorly. Postocular sides of cranium contour frontal view shape: broadly convex. Vertex contour line in frontal view shape: straight; slightly concave. Vertex sculpture: main sculpture rugose, ground sculpture areolate. Gena contour line in frontal view shape: feebly convex. Genae contour from anterior view orientation: converging. Gena sculpture: rugo-reticulate with areolate ground sculpture. Concentric carinae laterally surrounding antennal foramen count: present. Eye length vs. absolute cephalic size (EL/CS): 0.230 [0.212, 0.248]. Frontal carina distance vs. absolute cephalic size (FRS/CS): 0.316 [0.289, 0.333]. Longitudinal carinae on median region of frons count: present. Longitudinal carinae on medial region of frons shape: forked. Smooth median region on frons count: absent. Antennomere count: 12. Scape length vs. absolute cephalic size (SL/CS): 0.895 [0.861, 0.927]. Facial area of the scape absolute setal angle: setae absent, pubescence only. Median clypeal notch count: present. Median clypeal notch depth vs. absolute cephalic size (Cdep/CS): 0.022 [0.015, 0.029]. Ground sculpture of submedian area of clypeus: smooth. Median carina of clypeus count: present. Lateral carinae of clypeus count: present. Median anatomical line of propodeal spine angle value to Weber length in lateral view: 55–60°. Spine length vs. absolute cephalic size (SPST/CS): 0.398 [0.355, 0.427]. Minimum spine distance vs. absolute cephalic size (SPBA/CS): 0.287 [0.257, 0.311]. Apical spine distance vs. absolute cephalic size (SPTI/CS): 0.543 [0.463, 0.607]. Propodeal spine shape: strongly bent. Apical distance of pronotal spines vs. absolute cephalic size (PSTI/CS): 0.724 [0.631, 0.776]. Metanotal depression count: absent. Dorsal region of mesosoma sculpture: areolate ground sculpture, superimposed by dispersed rugae. Lateral region of pronotum sculpture: areolate ground sculpture, superimposed by dispersed rugae. Mesopleuron sculpture: areolate ground sculpture superimposed by dispersed rugulae; areolate ground sculpture, superimposed by dispersed rugae. Metapleuron sculpture: areolate ground sculpture, superimposed by dispersed rugae. Petiole width vs. absolute cephalic size (PEW/CS): 0.307 [0.275, 0.357]. Anterodorsal spines on petiolar node angle of deviation from each other: 80°. Apical distance of anterodorsal spines on petiolar node vs. absolute cephalic size (NSTI/CS): 0.514 [0.473, 0.563]. Frontal profile of petiolar node contour line in lateral view shape: convex. Dorso-caudal petiolar profile contour line in lateral view shape: convex. Dorsal region of petiole sculpture: ground sculpture areolate, main sculpture dispersed rugose. Postpetiole width vs. absolute cephalic size (PPW/CS): 0.538 [0.494, 0.576]. Dorsal region of postpetiole sculpture: ground sculpture areolate, main sculpture dispersed rugose.

Type Material
Holotype worker. CASENT0460666, collection code: BLF06010; MADG’R: Prov. Toliara, Forêt de Tsinjoriaky, 6.2 km 84° E Tsifota, 22°48'S, 43°25'E [-22.80222N, 43.42067E], 70 m, 6–10.iii.2002 Fisher et al. Paratypes. Ten workers, a single gyne and two males with the same label data as the holotype (CAS).

Etymology
This Malagasy word “hafahafa” means weird, and refers to the unusual morphology of this species.