Royidris pallida Bolton & Fisher

Bolton, Barry & Fisher, Brian, 2014, The Madagascan endemic myrmicine ants related to Eutetramorium (Hymenoptera: Formicidae): taxonomy of the genera Eutetramorium Emery, Malagidris nom. n., Myrmisaraka gen. n., Royidris gen. n., and Vitsika gen. n .., Zootaxa 3791 (1), pp. 1-99 : 59-60

Royidris pallida Bolton & Fisher sp. n.

(Figs 63-65, Map 143)

HOLOTYPE WORKER. TL 2.5, HL 0.59, HW 0.50, CI 85, SL 0.50, SI 100, PW 0.34, WL 0.72.

Antennal club 3-segmented. Mandible with superficial longitudinal costulae and scattered pits. Scapes relatively short (SI 100); when laid straight back in full-face view the apex of the scape just exceeds the posterior margin of the head. With head in full-face view the eyes very close to the midlength of the side of the head capsule. EL 0.14 (EL/HW 0.28). Dorsum of head from level of eyes to posterior margin smooth and polished; at high magnification some vestiges of superficial reticular patterning are visible, which appear to be the last traces of an almost entirely effaced microreticular pattern. Promesonotum in profile convex and swollen, domed, the mesonotum posteriorly descends abruptly to the commencement of the propodeum, the metanotal groove is absent. In absolute profile the propodeal dorsum is very slightly concave in its anterior one-third, slightly convex in its posterior two-thirds, and ends posteriorly in a bluntly reinforced angle that slightly overhangs the shallowly concave declivity. The whole propodeal dorsum is strongly depressed with respect to the highest point of the promesonotum, which is on a considerably higher level. Dorsa of pronotum and mesonotum each with 2 pairs of setae; dorsum of propodeum lacks setae. Promesonotal dorsum smooth and shining, with vestigial traces of microreticular patterning. Propodeal dorsum very feebly sculptured, but distinctly more strongly than the pronotum. Mesopleuron and metapleuron weakly shagreenate to very feebly, superficially reticulate-punctulate. Metafemur relatively slender, MfL 0.56 (MfL/HW 1.12, MfL/MfH 5.60). Petiole with a pair of setae on the posterior face of the node; postpetiole with a pair dorsally and a transverse row of 4 posteriorly; first gastral tergite with short setae that are quite densely scattered over the entire dorsum. Postpetiole relatively narrow in dorsal view, maximum width 0.22 (0.36 x HW). Dorsum of postpetiole and first gastral tergite unsculptured. Colour of head, mesosoma, petiole and postpetiole yellow, the legs and gaster conspicuously lighter, extremely pale yellow to almost white.

QUEEN and MALE: unknown.

Holotype worker, Madagasacar: Prov. Toliara, Foret Tsinjoriaky, 6.2 km. 84° E Tsifota, 22°48'S, 43°25'E, 70 m., 6-10.iii.2002, BLF 5967, CASENT0085017, at light, spiny forest/thicket (Fisher et al.) (CASC).

Within the robertsoni group, pallida is recognised by its pale colour, smooth head, lack of a metanotal groove, relatively short scapes, and relatively slender metafemora.

Known only from the holotype, this beautiful little species was included by Heterick (2006) under clarinodis . The single specimen was foraging nocturnally, at a light trap.