Chelaner longiceps

In Australian mainland states Monomorium longiceps is a relatively common and widespread red or red-and-brown ant that has been collected from both ground and vegetation. Some populations can still be found in relictual bushland in the Perth metropolitan area and on Rottnest Island (Heterick 2009).

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  longiceps. Monomorium (Notomyrmex) longiceps Wheeler, W.M. 1934d: 146 (w.) AUSTRALIA. Heterick, 2001: 432 (q.). Combination in Chelaner: Ettershank, 1966: 97; in Monomorium: Taylor, 1987b: 3.

Worker
Length 2.3-2.8 mm.

Averaging slightly smaller than Monomorium insolescens and differing in the following characters: Head trapezoidal, longer, narrower and more distinctly broader in front than behind, with straight sides; eyes smaller and nearer the middle of the sides; mandibles narrower, 4-toothed; antennal scapes shorter as are also joints 2-8 of the funiculus. Epinotum in profile rectangular, the declivity perpendicular, with the denticles larger and continued as crenulated ridges to the metasternal angles, which are small and poorly developed. Peduncle of petiole longer, more sharply marked off from the node. This and the postpetiole are of the same width but much more rounded and less cuboidal than in insolescens; petiolar node from above as long as broad, rather narrowly rounded in front, contracted behind; postpetiole subtrapezoidal one and one-third times as broad as long, broader in front than behind, with rounded corners and short, straight, posteriorly converging sides.

Sculpture of the head similar to that of insolescens, but the longitudinal rugules are continued back beyond its middle and the sparse punctures on its posterior portion are coarser. Mandibles rather coarsely striate-punctate. Thorax longitudinally rugulose throughout, except the declivity of the epinotum which is transversely striate; dorsal portion of pronotum more loosely rugose and therefore more shining than the remainder of the thorax. Petiolar node above arcuately rugulose; postpetiole with a few short, longitudinal sulci. Gaster smooth and shining, with very sparsely, piligerous punctures.

Pilosity somewhat more abundant than in insolescens.

Colour of the head and thorax the same, but the gaster is also red and not yellow and the antennae and legs are brownish red, darker than the head and thorax, the tarsi paler.

Type Material
Described from a single specimen which I found running on the ground near Lady Edeline Beach (X.23.'31), and two workers from Ludlow, Western Australia, received from Mr. John Clark.