Camponotus fieldeae

Identification
McArthur and Leys (2006), discussing C. spenceri: Camponotus maculatus group species share the following distinguishing characters: 1. The most striking character is the distinct occipital carina in minor workers (see the dorsal head view of the minor worker in the caste images of Camponotus crozieri). This forms a ridge externally and probably serves to strengthen the anterior parts of the head (Snodgrass 1935), it is absent in major workers. 2. Strong dimorphism, i.e., workers encountered are mostly either major or minor, medium workers are non existent or very scarce. 3. The sides of the heads of major workers taper strongly to the front (Fig. 2) while in minor workers, the sides are mostly parallel and taper to the rear. 4. The vertex in major workers is concave or flat, in minor workers it is convex. 5. The scape and tibiae have plentiful short setae, raised up, more so in Australian than in African species. 6. Biology: (a) mostly nocturnal, (b) nests are at honey bait, (e) quickly scatter when disturbed by torch light.

McArthur (2009), discussing C. xuthus: The integument of the gaster in C. xuthus in not hidden by pubescence and the ant is brown whereas Camponotus nigroaeneus has distinct short whitish decumbent setae (pubescence) which hide the gaster and is mostly black.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 * . Camponotus fieldeae Forel, 1902h: 495 (s.w.) AUSTRALIA (Queensland).
 * Combination in C. (Myrmoturba): Forel, 1914a: 267;
 * combination in C. (Tanaemyrmex): Emery, 1925b: 90.
 * Status as species: Emery, 1925b: 90; Taylor & Brown, 1985: 114; Taylor, 1987a: 12; Bolton, 1995b: 99; McArthur, 2007a: 329; McArthur, 2014: 86.
 * reticulatus. Camponotus reticulatus Kirby, W.F. 1896: 204 (s.w.) AUSTRALIA (Northern Territory).
 * [Junior primary homonym of Camponotus reticulatus Roger, 1863a: 139.]
 * Replacement name: Camponotus (Tanaemyrmex) spenceri Clark, 1930c: 18.
 * spenceri. Camponotus (Tanaemyrmex) spenceri Clark, 1930c: 18.
 * [Misspelled as spenseri by McArthur, 2007a: 296.]
 * Replacement name for Camponotus reticulatus Kirby, W.F. 1896: 204. [Junior primary homonym of Camponotus reticulatus Roger, 1863a: 139.]
 * Status as species: Taylor & Brown, 1985: 119; Taylor, 1987a: 15; Bolton, 1995b: 124; McArthur, 2007a: 329; McArthur, 2010: 100; Pfeiffer, et al. 2011: 38 (error); Guénard & Dunn, 2012: 30 (error); McArthur, 2014: 94.
 * Junior synonym of fieldeae: Heterick, 2021: 18.
 * [Note: Pfeiffer, et al. 2011: 38, and Guénard & Dunn, 2012: 30, include spenceri Clark in error as a species of Borneo and China, respectively; spenceri is the replacement name for reticulatus Kirby, W.F. 1896 (Australia), not for reticulatus Roger, 1863a (Oriental region).]
 * xuthus. Camponotus (Myrmophyma) nigroaeneus subsp. xuthus Emery, 1925b: 111.
 * [First available use of Camponotus (Myrmoturba) nigroaeneus r. divus var. xuthus Forel, 1915b: 97 (s.w.) AUSTRALIA (Western Australia); unavailable (infrasubspecific) name (Taylor, 1986: 34).]
 * Status as species: McArthur, 2009: 285 (redescription).
 * Subspecies of nigroaeneus: Taylor, 1987a: 14; Bolton, 1995b: 130; McArthur, 2014: 90.
 * Junior synonym of fieldeae: Heterick, 2021: 18.

Taxonomic Notes
Heterick (2021): Based on Automontage photographs of type material for Camponotus spenceri and C. nigroaeneus xuthus, there is a strong argument that these two names should become junior synonyms under C. fieldeae. Note: the relegation of C. nigroaeneus xuthus to a subspecies again by McArthur (2014) after he had raised it to species (McArthur 2009) is puzzling and not explained in his later work.

Description
Workers. Length 4.7-8 mm. Very similar to C. extensus while being smaller. Worker major. Mandibles strongly curved on the outer edge, smooth and glossy towards the extremities, weakly shagreen towards the base, with scattered or sparse points and probably 7 teeth. The head is trapezoidal, the sides convex, strongly widened and indented behind, more widened behind and shorter than extensus. Clypeus keeled, the lobe like extensus is a little indented in the middle of its anterior edge. Thorax much shorter than extensus; pronotum much wider than long; the declivity of the metanotum (= propodeum) only a little shorter than the basal face; metanotum (= propodeum) not so low. The node is a little less thick. Limbs and antennae shorter. The head is entirely dull, densely reticulate punctate; thorax a little more sub opaque; gaster moderately glossy. The tibias and scapes have short hairs, semi erect, abundant. The rest of the sculpture as with extensus. Pubescence is very dilute. The color is dark brown, the limbs, mandibles and the funicles a light brown. Worker minor. The head has a distinct posterior border (not like extensus), only 1/4 to 1/3 longer than wide (with extensus the length is almost twice the width) and as wide at the back as it is at the front (very narrow behind in the case of extensus). Pronotum with width equal to its length (with extensus length is longer than width). In other respects the thorax is like the major worker. Node half as thin as extensus. Sculpture, pilosity and color like the major worker. Clypeus with an anterior lobe which is very rectangular, with a straight border, and sharply keeled. Charters Towers, Queensland (Wiederhehr) A variety with a little weaker sculpture (head sub opaque), with thorax a little more convex and the declivity shorter, in other respects identical with the specimen from Townsville, Queensland from M Gilbert Turner A species closely related to extensus but with the stature of the group maculatus from which it differs by its pilosity.

References based on Global Ant Biodiversity Informatics

 * Andersen A. N., B. D. Hoffmann, W. J. Muller, and A. D. Griffiths. 2002. Using ants as bioindicators in land management: simplifying assesment of ant community responses. Journal of Applied Ecology 39: 8-17.
 * Andersen A. N., B. D. Hoffmann, and S. Oberprieler. 2016. Diversity and biogeography of a species-rich ant fauna of the Australian seasonal tropics. Insect Science DOI 10.1111/1744-7917.12402
 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * 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.
 * Majer J. D., S. K. Callan, K. Edwards, N. R. Gunawardene, and C. K. Taylor. 2013. Baseline survey of the terrestrial invertebrate fauna of Barrow Island. Records of the Western Australian Museum Supplement 83: 13-112.
 * McArthur A. 2010. A guide to Camponotus ants of South Australia. Adelaide: South Australian Museum, IV + 121 pp.
 * Pfeiffer M.; Mezger, D.; Hosoishi, S.; Bakhtiar, E. Y.; Kohout, R. J. 2011. The Formicidae of Borneo (Insecta: Hymenoptera): a preliminary species list. Asian Myrmecology 4:9-58
 * Yusah K. M., T. M. Fayle, G. Harris, and W. A. Foster. 2012. Optimizing diversity assesment protocols for high canopy ants in tropical rain forest. Biotropica 44(1): 73-81.