Polyrhachis dubia Rigato, 2016, n. sp

<i>Polyrhachis dubia</i> n. sp. (Figures 3 a–c) <b>Diagnosis.</b> A medium-sized species in the <i>revoili</i> -group, with convex anterior clypeal margin, immarginate mesosoma, minute pronotal teeth, very weak propodeal ridges and relatively abundant fine standing hairs on body and appendages. <i>Holotype worker</i>. HL 1.47, HW 1.21, CI 82, SL 1.66, SI 137, FW 0.44, FI 36, PW 0.95, WL 1.88, HTL 1.56. Clypeus ecarinate and with evenly convex anterior margin. Head in full face view oval, with anteriorly converging sides and convex posterior border. Eyes moderately developed and convex. Mesosoma stout, immarginate, in profile more convex anteriorly than posteriorly. Pronotal teeth minute, their anterior edge perpendicular to the longitudinal axis of the body. Propodeal dorsum posterolaterally bearing a pair of weak ridges. Promesonotal suture visible, metanotal suture hardly so. Petiole with a median pair of moderately long, slightly diverging spines and a lateral pair of small teeth. In frontal (or posterior) view the space between the spines evenly shallowly concave. First gastral tergite anteriorly weakly concave. Mandibles weakly striolate and with sparse piligerous pits. Head, mesosoma and petiole mostly reticulatepunctate. A superimposed irregular rugosity occurs on the head (except clypeus), and a finer, mostly longitudinal irregular rugulosity on the mesosoma. Appendages finely reticulate-punctate and subopaque. Head and mesosoma feebly shining; gaster superficially sculptured and shining. Standing, pale, thin and flexuous hairs of uneven length are fairly abundant on body and appendages; on average they are slightly shorter on gaster and even shorter on legs and funiculi. Longest hairs on scapes easily surpass maximum scape width, on the tibiae always shorter than maximum tibial width. Pubescence whitish, relatively dense, especially on mesosoma, petiole and gaster; shorter and more regularly arranged on the latter. Body and coxae black, antennae, mandibles and remaining leg segments mostly ferrugineous. [...]