Camponotus sponsorum

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  sponsorum. Camponotus sponsorum Forel, 1910b: 76 (s.w.m.) AUSTRALIA. Combination in C. (Myrmophyma): Forel, 1912i: 91.

Description
Workers. 2.4 to 7 mm. Worker major. Mandibles short, glossy, strongly and abundantly punctate, finely shagreen towards the base, armed with 6 teeth. Anterior margin of clypeus profoundly bidented with a third median indentation less deep between the two teeth. Median portion of the clypeus scarcely sub keeled, wider than long, sub hexagonally rounded,its sides being a little stretched out into an angle. Frontal area rhombiform; frontal ridges long, sinuous, diverging a little. The sides of the clypeus are very short and partly hidden under the cheeks. Head is convex at the top, rectangular, elongated 1.8 mm long and 1.5 mm wide, scarcely wider behind than at the front, sides scarcely convex. Viewed exactly from the front, the posterior border is distinctly convex, particularly in the middle, where the occiput has a distinct swelling. Viewed from behind it is excavated. The eyes are quite flat slightly in front of the posterior third. The 3 occelli pits are empty. The scape passes the posterior border by less than its thickness in the major worker. The occipital border has a distinct convex scollop in the middle corresponding with the swelling. Scape a little wider towards the extremity. Head not at all subtruncated at the front. Thorax very humped from head to basal face of the epinotum, and moreover very convex transversely. Pro-mesonotum suture profound, a little surpassed by the mesonotum. The basal face of the epinotum is rather wide, very slightly concave in the shape of a saddle in longitudinal profile it descends a little longer than the declivity, which is obliquely truncate and slightly concave as well (also more distinctly). Node moderately thick, convex in front,flat behind, superior edge scarcely sharp and sub accuminate. Gaster quite large and long. Tibias cylindrical with a range of small barbs on the internal face. Glossy, feebly shagreen (thorax a little more strongly than the head), on the gaster strictly transverse. Punctation sparse very fine, piligerous,indistinct, a little more distinct on the head. A few erect sparse yellowish hairs on the body; none on the limbs. Pubescence adpressed and very fine and very sparse, arising from these points. Head and thorax, with antennae, tarses and mandibles of a red more or less brownish with a few brown spots on the thorax. The gaster black with the edge of the segments yellow; the limbs yellow a little reddish towards the base (tibias). Worker minor. Mandibles similar to the major worker. Clypeus with keel, advanced at the front into a rounded lobe, without indentations or teeth, strongly convex, trapezoidal, wider at the front. Head absolutely like the major worker, not narrower behind, but without a swelling; the posterior border seen from the front is precisely convex (without scallop more convex in the middle). Eyes quite convex, on the posterior quarter. Scapes scarcely not wider at their extremity, exceed the posterior head by almost half. Node quite thick and low, as thick at the summit which is transverse as at the base. Basal face of the epinotum is twice as long as the declivity, strongly concave like a saddle in profile (more than the declivity). Otherwise like the worker major but sub opaque with a sculpture more dense more reticulate and a pubescence  which is yellowish and much more abundant forming a light gray duvet, especially on the gaster. Front of the vertex and pronotum entirely brown; the limbs are the same color as the head and thorax. Tennants Creek, Central Australia. (Field). This species is very curious by the form of the head, and by the great dimorphism within the workers, without noticeable difference in the form of the head. The teeth of the clypeus of the major worker make it more like claripes and especially like isabella Forel of Ceylon. Its occipital hump makes it resemble capito Mayr and fieldellus Forel but it is weaker so it is placed elsewhere.

References based on Global Ant Biodiversity Informatics

 * Heterick B. E. 2009. A guide to the ants of south-western Australia. Records of the Western Australian Museum Supplement 76: 1-206.
 * Heterick B. E., B. Durrant, and N. R. Gunawardene. 2010. The ant fauna of the Pilbara Bioregion, Western Australia. Records of the Western Australian Museum, Supplement 78: 157-167.
 * McArthur A. 2010. A guide to Camponotus ants of South Australia. Adelaide: South Australian Museum, IV + 121 pp.
 * Taylor R. W. 1987. A checklist of the ants of Australia, New Caledonia and New Zealand (Hymenoptera: Formicidae). CSIRO (Commonwealth Scientific and Industrial Research Organization) Division of Entomology Report 41: 1-92.