Royidris longiseta 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 : 55-57

Royidris longiseta Bolton & Fisher sp. n.

(Figs 57-59, Map 141)

WORKER (holotype in parentheses). TL 2.7-3.0 (2.7), HL 0.64-0.67 (0.66), HW 0.54-0.56 (0.54), CI 82-84 (82), SL 0.54-0.59 (0.59), SI 100-109 (109), PW 0.36-0.38 (0.36), WL 0.80 - 0.82 (0.80) (3 measured).

Antennal club 4-segmented. Mandible longitudinally costulate. Scapes of moderate relative length (SI 100-109); when laid straight back in full-face view the apex of the scape slightly 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 0.16-0.18 (EL/HW 0.30-0.33). Dorsum of head from level of eyes to posterior margin finely reticulate-punctate, the sculpture uniform, effaced in places, or fading out posteriorly. Promesonotum in profile convex and swollen, the mesonotum posteriorly descends abruptly to a small, weakly incised metanotal groove. In absolute profile the propodeal dorsum is horizontal and flat, or very nearly flat; posteriorly dorsum meets the declivity in a rounded right-angle and the declivity is straight and almost vertical. The whole propodeal dorsum is strongly depressed with respect to the highest point of the promesonotum, which is on a considerably higher level. Pronotum with 4-5 pairs of setae; mesonotum with 3-4 pairs; on both pronotum and mesonotum the longest setae are longer than the maximum vertical diameter of the eye. Dorsum of propodeum with 2-3 pairs of short, standing setae that are less then half the length of those on the mesonotum. Petiole node with 3-4 pairs of setae that arise from the apex and posterior face of the node; postpetiole with numerous long setae that arise from the anterior, dorsal and posterior surfaces of the node; first gastral tergite with numerous long, suberect setae that are at least subequal to the maximum vertical diameter of the eye. Entire dorsum of mesosoma finely and densely reticulate-punctate in typematerial, the sculpture of about equal density and intensity everywhere, or weaker on the pronotum (superficial on pronotum in the non-paratypic specimens). Pronotum also with weak transverse striolae in the type-series, but not in the non-paratypic workers. Entire side of mesosoma finely and densely reticulate-punctate, the sculpture of approximately equal density and intensity everywhere in the paratype, but weaker on the pronotum than the mesopleuron in the holotype and partially effaced in the non-paratypic workers. Metafemur with MfL 0.55-0.58 (MfL/HW 1.02-1.07, MfL/MfH 3.63-3.73). Postpetiole relatively narrow in dorsal view, maximum width 0.20-0.21 (0.36-0.39 x HW). First gastral tergite glassy smooth, without trace of superficial microreticulate sculpture. Colour of mesosoma, petiole and postpetiole brown to orange-brown, the head somewhat darker than the mesosoma; the gaster glossy dark brown to black.

QUEEN and MALE: unknown.

Holotype worker, Madagascar: Prov. Toliara, Mahafaly Plateau, 6.2 km. 74° ENE Itampolo, 24°39'S, 43°69'E, 80 m., 21-25.ii.2002, BLF 5763, CASENT0078298, pitfall trap, spiny forest/thicket (Fisher et al.) (CASC).

Paratype. 1 worker, Prov. Toliara, Tsivory, 24°04.24'S, 46°04.52'E, 400 m., 9.xii.2006, BLF 15869, CASENT0120216, urban/garden (Fisher et al.) (CASC).

The holotype of this species was included as part of shuckardi by Heterick (2006). R. longiseta is closest related to gravipuncta , but has distinctly longer promesontal and gastral setae, and also has short erect setae present on the propodeal dorsum.

Only four specimens are referable to this species, one collected from a pitfall trap in spiny forest, two from urban gardens, and one in shrubland. In the paratype and the non-paratypic workers some suberect pubescence is present on the side of the head below the eye, which may be visible in full-face, projecting from below the eye. This feature is absent from the holotype, and its significance is not understood at present.

Non-paratypic material examined. Madagascar: Prov. Fianarantsoa, Ihosy (Fisher et al.); Ranohira, Ampandravelo (A. Ravelomanana).