(Figs 11, 25, 43, 54, 93, 127)

Description. Female. Fore wing 9.8 mm. Head: Antenna with 30–31 flagellomeres. Clypeus entirely punctate, smooth towards apex, markedly convex, most prominent ventrally, CWH 1.64; MWC 0.67, MLW 1.77, MWW 0.55; malar space moderately long, MSM 1.20; supra-antennal area with almost indistinct, median, longitudinal carina; minimum distance from eye margin to occipital carina laterally approximately same width of mandible base.

Mesosoma (Fig. 93). Pronotum lateral portion distinctly strigate to rugose, epomia moderately marked; notaulus moderately impressed, inconspicuously, minutely corrugated, especially anteriorly, reaching about middle of mesoscutum (Fig. 43); mesopleuron dorsal half medially strigulate, ventral half posteriorly strigate with ridges taking mesopleural groove, epicnemial carina restricted to ventral 0.8 of mesopleuron, posteriorly inconspicuously, densely corrugated; mesopleural groove markedly, sparsely corrugated; sternaulus entirely markedly corrugated; postpectal carina medially distinctly bent; metapleuron, subapical fovea shallow, subcircular; pleural carina stout; propodeum anterior area short, PLL 0.48, anterior transverse carina distinct, complete, medially distinctly arched forwards (Fig. 11), posterior area markedly strigate-rugose, with ridges medially slightly arched backwards, spiracle very elongate, SWL 2.88 (Fig. 54), propodeal apophyses short, conical, AHD 1.43. Legs: Hind t4 posterior lobe about 0.75 × as long as anterior lobe. Wings (Fig. 25): Fore wing vein (Rs+M)b slightly but uniformly curved, limit with crossvein 1m-cu indistinct, ramellus absent; vein Rs&1M posteriorly slightly curved; crossvein 1cu-a uniformly slightly convex, arising opposite vein Rs&1M, angle with vein M+Cu about 90 degrees; vein 2Cua moderately shorter than crossvein 2cu-a, FWC 0.72; areolet small, APH 0.84; vein 2Ma distinctly longer than vein 2Mb; vein 2Mb tubular; crossvein 2m-cu with bulla short, about 0.2 × as long as vein length or shorter; vein 2Rsb sinuous. Hind wing vein 2-1A long, reaching about 0.8 × the distance to wing margin, HWC 1.72.

Metasoma (Fig. 93). T1 petiole basal half smooth towards base, apical half, postpetiole coriarious-punctulate, except pospetiole apical parts centrally smooth, sparsely punctulate, spiracle at about basal 0.6, inconspicuously prominent, T1LW 3.17, T1WW 2.61, T1GL 0.32; T2 moderately short, apically robust, T2T1L 0.74, thyridium subcircular, T2LW 1.09, T2WW 1.93. Ovipositor slightly but uniformly downcurved, OST 0.69, dorsal valve with nodus faint, notch present; ventral valve tip with inconspicuous serrations restricted to very tip.

Color. Head, mesosoma, legs and metasoma black. Head: Dorsal portion of flagellomeres 5–9 and mouth parts, except mandible, white. Mesosoma: Propodeal apophyses white. Legs: Trochanters apical margin white; fore femur anteriorly whitish towards apex; fore and mid tibiae anteriorly and posteriorly pale yellow (222, 194, 099); fore and mid tarsomeres brownish (180, 104, 061). Wings: With uniform yellowish tint (Fig. 25). Metasoma: T1 apical margin with central semicircular mark light brown; apical margin of T2 and 3 often whitish; sternites medially white; ovipositor sheath dark brown, except basal 0.6 ventrally whitish; ovipositor brown (144, 088, 056).

Male. Unknown.

Variability. Paratype fore wing crossvein 1cu-a slightly convex and arising almost indistinctly apicad vein Rs& 1M.

Comments. Included in the D. soror species group (see item Species Delimitation). Individuals of D. palaior are conspicuous among other species of the group by having the wings with uniform yellowish tint (vs. entirely hyaline) and general body sculpturation more marked, such as the pronotum lateral portion distinctly strigate to rugose (vs. next to collar inconspicuously strigate-rugose, and next to mesopleuron inconspicuously corrugated), epomia moderately stout (vs. delicate), notaulus moderately impressed (vs. inconspicuously impressed), and mesopleuron dorsal half medially strigulate, ventral half posteriorly strigate with ridges taking mesopleural groove (vs. dorsal half medially faintly strigulate-rugulose, ventral half without distinct ridges or rugae).

Etymology. From the Greek word palaion, meaning “aged, ancient,” in reference to the wings with yellowish tint, giving this species an aged appearance.

Distribution. Recorded from Peru, on the locality of Ucayali, Tingo María (09°08.2’S 75°47.3’W); and Ecuador, on Cordillera Cutucú, at Morona-Santiago (around 02°19’S 78°07’W) (Fig. 127).

Material Examined. 2 ♀. Holotype ♀ from PERU, Ucayali, Tingo María, Pacalpard, km 205, 1300 m, flight interception trap, 09°08.2’S 75°47.3’W, 11–14.X.1999, RBrooks leg. (CNCI). In good shape, mounted on triangle point. Paratype: ECUADOR: 1 ♀ from Morona-Santiago, Cord. De Cutucu, 6 km east of Macas, 1,100 m, 28.III.1981, MCooper, Debilos sp. AMTedesco det. 2009 (BMNH).