Probolomyrmex salomonis

This species is restricted to the Solomon Islands where it is known from a handful of collections made in forested situations. The holotype was collected in a Berlese funnel sample of leaf mould from the floor of undisturbed rainforest, at an elevation of about 1000 feet.

Identification
Petiolar node relatively long and narrow (best viewed dorsally), the dorsal face (in side view) uniformly convex and without a separation of the anterior and dorsal faces; anterior projection of the subpetiolar process broadly rounded, the posterior projection in the form of a blunt tooth.

Probolomyrmex salomonis is most similar to Probolomyrmex simplex from Papua New Guinea. It differs in having the anteroventral tooth of the subpetiolar process broadly rounded rather than narrow and tooth-like, the lateral flanges on the posterior face of the propodeum more weakly developed and in having the foveae on the mesosoma and gaster more strongly developed.

Key to Australian and Melanesian Probolomyrmex species

Distribution based on Regional Taxon Lists
Indo-Australian Region: Solomon Islands.

Nomenclature

 *  salomonis. Probolomyrmex salomonis Taylor, 1965d: 358, figs. 20, 21 (w.) SOLOMON IS. See also: Shattuck, Gunawardene & Heterick, 2012: 47.

Worker
HL, 0.59 mm.; HW, 0.38 mm.; SL, 0.37 mm.; Cl, 64; SI, 97; WL, 0.79 mm.; PW, 0.30 mm.; dorsal petiole width, 0.17 mm,; petiolar node index, 57; petiolar height, 0.28 mm.; petiolar node length, 0•26 mm.; lateral petiolar index, 93. Habitus similar to that of Probolomyrmex dammermani and Probolomyrmex greavesi. Head narrower than in these species, with occipital border moderately concave. Scapes relatively as long as in dammermani, somewhat longer than in greavesi. Eyeless. Mandible with a large acute apical tooth followed by a series of six denticles, distal one of which slightly enlarged. Visible terminal maxillary and labial palpomeres proportioned as in Probolomyrmex angusticeps. General form of mesosoma as in P. dammermani. Declivitous face of propodeum, viewed from above, moderately concave, depth of concavity about one-third distance between dorsal corners of posterolateral propodeal lamellae. Posterior face moderately concave in side view, its surrounding flange feebly emarginate at dorsal mid-line. Subpetiolar process well developed, similar to that of P. greavesi, but shallower and with ventral edge distinctly concave in side view.

Pilosity reduced, as is normal for the genus; pubescence extremely fine and very sparse, most abundant on second segment of gaster, virtually lacking on head, mesosoma and node. Sculpturation almost exactly as described above for P. dammermani. Colour rich golden-brown, as in the type of P. dammermani.

Type Material
Holotype worker. SOLOMON ISLANDS: Guadalcanal, Mt. Austen, Honiara, 25.ii.1963 (P. J. M. Greenslade). The unique holotype is deposited in the Museum of Comparative Zoology, Harvard University.