Bolton, B., 1979:
( Fig. 56)
Holotype worker. TL 3.9, HL 0.92, HW 0.84, CI 91, SL 0.78, SI 93, PW 067, AL 1.14.
Antennae with 11 segments. Mandibles finely longitudinally striate. Clypeus without a median notch but the anterior apron with a feeble impression. Frontal carinae long and strong, sinuate, almost reaching occiput before becoming indistinguishable from remaining rugose sculpture. Propodeal spines long and narrow, slightly upcurved apically in profile. Metapleural lobes elongate-triangular. Node of petiole in profile long and low, with a short anterior face, a long, gently convex dorsum and a long posterior face, the posterodorsal angle rounded; postpetiole in profile low and evenly shallowly convex dorsally. Petiole in dorsal view longer than broad. Entire dorsum of head coarsely reticulate-rugose, the clypeus similarly sculptured and without a median longitudinal carina. Dorsal alitrunk coarsely reticulate-rugose as the head, the reticular spaces on both head and alitrunk mostly smooth, with only very feeble superficial ground-sculpture. Sides of petiole and postpetiole rugulose, the latter more feebly so than the former. Dorsum of petiole with an unsculptured shining median longitudinal strip, dorsum of postpetiole unsculptured. First gastral tergite unsculptured, smooth and shining. All dorsal surfaces of head and body with numerous elongate hairs, the largest of those on the alitrunk longer than those on the first gastral tergite. Dorsal (outer) surfaces of hind tibiae with scattered short, erect to suberect hairs, the scapes with short fine hairs. Colour blackish brown.
Paratype workers. As holotype, the colour varying from dark brown to almost black and with a range of dimensions TL 3.7 - 4.0, HL 0.86 - 0.94, HW 0.78 - 0.86, CI 90 - 93, SL 0.72 - 0.80, SI 90 - 95, PW 0.62 - 0.70, AL 1.06 - 1.18 (34 measured).
Holotype worker, Borneo: Sarawak, 4 th Division, Gunong Mulu Nat. Pk, R. G. S. Expd., Long Pala, 19. ix. 1977, lowl. rainfor., soil pocket on rock (B. Bolton) (BMNH).
Paratypes. 27 workers with same data as holotype and 24 workers with same data but 20. ix. 1977 (BMNH; MCZ, Cambridge; NM, Basle; USNM, Washington; MHN, Geneva).
Very closely related to vertigum Bolton of Sulawesi and running to that species in the key (Bolton, 1977: 73); palaense is best separated as follows.
Frontal carinae strong, almost reaching to occiput.
Antennal scrobes developed.
Posterior face of petiole not convex in profile, not overhanging petiole-postpetiole junction.
Side of postpetiole rugulose.
Antennal scapes shorter, SI 90 - 95.
Anterior clypeal apron slightly indented medially.
Frontal carinae weak, quickly fading out behind level of eyes.
Antennal scrobes vestigial.
Posterior face of petiole convex in profile, overhanging petiole-postpetiole junction.
Sides of postpetiole smooth.
Antennal scapes longer, SI 97 - 105.
Anterior clypeal apron evenly convex.