Camponotus intrepidus

Camponotus intrepidus is common within its range and constructs large soil mound nests with a thatch covering of charcoal, leaves and twigs. The covering appears to protect the mound from rainsplash erosion. Activity is nocturnal (unless disturbed) (Cowan et al., 1985).

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Cowan et al. (1985) report that nests are partly shaded by overhanging shrubs and trees and the above-ground part of each nest is an earthen mound, constructed around two or three clumps of grass or sedges and crudely thatched with leaves, twigs and charcoal fragments worked into the mineral soil on the mound surface. The sides of the mound are sometimes fluted, and in such cases the debris cover is incomplete. During their study period (August to January) there were no visible entrance holes on any mound and, in order to make the nest casts, it was necessary to lift off a 1 cm thick surface crust from the mound to gain access to the galleries. The mounds varied in ground-surface area from 0.05 to 1.19 m2, were commonly elliptical, and rather peaked, with a mean height of 20.4 cm.

Nest excavation revealed that most ant galleries were located in the mound and in the A horizon of the soil. A few galleries extended to the C horizon of grey plastic clay at a maximum depth of 90 cm. While the sectioning technique did not give a clear view of the entire nest structure, it did indicate that the galleries interconnected only within the mound. Below this there were several independent open spirals, each serving 8-12 chambers. Galleries within the mound had 'glazed' walls 2-3 mm thick of a colour darker than the mound itself. Macerated fine organic matter (leaves, rootlets) were incorporated in this glaze and were visually estimated to comprise 20% of the wall material. Termite galleries and the nest of a small black undetermined ant species shared the mound, but neither of these nests connected with ‘’Camponotus’’ galleries. With increased depth, the gallery wall glaze thinned to between 0.5 and 2 mm, and the colour became similar to the enclosing soil. Fine leaf material was used in the lining even at the base of the nest, and occasional large quartz grains and root tips extended through the lining into the galleries. The wall lining of chambers averaged 5 mm thick.

During excavation the mounds and upper parts of the nests were always seen to be drier than the adjacent soils. Soil moisture was measured on three occasions approximately 24 h after rain, and the results confirmed this observation.

Despite the impressive size of the nests and the selective use of materials, neither species is very significant in terms of soil mixing when compared with the smaller, more common ant Aphaenogaster longiceps.

Nomenclature

 * . Formica intrepida Kirby, W. 1819: 477 (w.) AUSTRALIA (New South Wales).
 * Lowne, 1865a: 277 (s.); Mayr, 1862: 659 (q.); Wheeler, G.C. & Wheeler, J. 1968: 218 (l.).
 * Combination in Camponotus: Mayr, 1862: 659;
 * combination in C. (Myrmosphincta): Forel, 1912i: 92;
 * combination in C. (Myrmosaulus): Emery, 1925b: 114.
 * Status as species: Smith, F. 1858b: 37; Mayr, 1862: 659 (redescription); Mayr, 1863: 399; Roger, 1863b: 4, 44; Mayr, 1865: 38; Lowne, 1865a: 277; Mayr, 1876: 58 (in key); Forel, 1879a: 91; Emery, 1887a: 210; Dalla Torre, 1893: 236; Emery, 1896d: 373 (in list); Forel, 1902h: 493; Emery, 1914b: 181; Forel, 1915b: 105; Emery, 1925b: 114; Clark, 1934c: 71; Taylor & Brown, 1985: 115; Taylor, 1987a: 13; Bolton, 1995b: 105; McArthur, 2007a: 320; McArthur, 2010: 88; McArthur, 2014: 106.
 * Senior synonym of agilis: Roger, 1863b: 4; Mayr, 1865: 38; Lowne, 1865a: 277; Mayr, 1876: 62; Dalla Torre, 1893: 236; Emery, 1896d: 373; Forel, 1902h: 493; Emery, 1925b: 114; Clark, 1934c: 71; Taylor & Brown, 1985: 115; Taylor, 1987a: 13; Bolton, 1995b: 105; McArthur, 2007a: 295; McArthur, 2010: 88.
 * Senior synonym of magnus: Roger, 1863b: 4; Mayr, 1865: 38; Mayr, 1876: 62; Dalla Torre, 1893: 236; Emery, 1896d: 373; Emery, 1925b: 114; Clark, 1934c: 71; Taylor & Brown, 1985: 115; Taylor, 1987a: 13; Bolton, 1995b: 105; McArthur, 2007a: 295; McArthur, 2010: 88.
 * Current subspecies: nominal plus bellicosus.
 * agilis. Formica agilis Smith, F. 1858b: 37 (w.) AUSTRALIA (no state data).
 * Combination in Camponotus: Roger, 1863b: 4.
 * Status as species: Mayr, 1863: 411.
 * Junior synonym of intrepidus: Roger, 1863b: 4; Mayr, 1865: 38; Lowne, 1865a: 277; Mayr, 1876: 62; Dalla Torre, 1893: 236; Emery, 1896d: 373; Forel, 1902h: 493; Emery, 1925b: 114; Clark, 1934c: 71; Taylor & Brown, 1985: 115; Taylor, 1987a: 13; Bolton, 1995b: 84; McArthur, 2007a: 295; McArthur, 2010: 88.
 * magnus. Camponotus magnus Mayr, 1862: 673 (w.q.) AUSTRALIA (New South Wales).
 * Status as species: Mayr, 1863: 400.
 * Junior synonym of intrepidus: Roger, 1863b: 4; Mayr, 1865: 38; Mayr, 1876: 62; Dalla Torre, 1893: 236; Emery, 1896d: 373; Emery, 1925b: 114; Clark, 1934c: 71; Taylor & Brown, 1985: 115; Taylor, 1987a: 13; Bolton, 1995b: 110; McArthur, 2007a: 295; McArthur, 2010: 88.

Description
Female

Black, red trunk and legs, with head larger than abdomen.

Length of the body 7 lines (= 14 mm).

Habitat in Australia near Port Jackson it is the most audacious and vigorous of all the Formica.

Close to F. rufae L. Body is a little shiny and black. The head is triangular, posteriorly sub emarginate and above is sparsely punctate and above is reticulate: very small openings. Stemmata inserted in pits in a triangle but the two posterior stemmata are hardly visible. Frons between the antennae is bi-carinate with very small carinae which are winding; the space between is grooved. Mandibles are very strong, punctate above,with 6 teeth. Antennae becoming reddish: scape is black. Clypeus keeled obtusely, emarginate. Thorax is compressed, with red legs; fumurs paler. Node is red, entire, hair tending to be coarse. Gaster sub ovate, black, almost hairy.

Formica agilis

Worker

Length 5 lines (= 10 mm) Head and abdomen black; antennae, thorax and legs ferruginous. Head oblong rounded behind; eyes ovate and prominent, placed backwards on the sides of the head; the clypeus with a central carina, its anterior margin,as well as that of the mandibles,ferruginous; the mandibles large, stout, triangular, and furnished with seven acute teeth within; antennae long and slender. Thorax long and narrow, and forming anteriorly a short neck; the posterior portion compressed, the metathorax rounded behind; legs elongate and slender. Abdomen ovate; the scale incrassate and nodose; the abdomen thinly sprinkled with long pale pubescence; the head and thorax, legs and antennae thinly covered with short pale pubescence. Hab. New Holland Smith, F. (1858), Formica intrepida Kirby. This species is probably the large form of F. basilis being the smaller form; this can only be decided upon by an examination of a community. F. intrepida has the head, the basal joint of the antennae, and the abdomen black; the thorax, scale and legs red; the scale is ovate and entire above; the extreme base of the scape is red; the inner margin of the mandibles is slightly rufo-piceous, and armed with six teeth; the length of the insect from the tip of the mandibles to the apex of the abdomen is 7 lines (= 14 mm). Hab. Australia. Forel (1902), Camponotus intrepidus Kirby (= agilis Smith): I have for a long time considered this race intrepidus. But it was an error. Kirby says that the head is black, submarginate behind and sparsely punctate, which is exactly the case of the form with the black head (agilis Smith). The true intrepidus is for the most part sub opaque with a glossy gaster.

References based on Global Ant Biodiversity Informatics

 * Andersen A.N., and M.E. McKaige. 1987. Ant communities at Rotamah Island, Victoria, with particular references to disturbance and Rhytidoponera tasmaniensis. Proc. R. Soc. Vict 99(4):141-146.
 * Emery C. 1914. Formiche d'Australia e di Samoa raccolte dal Prof. Silvestri nel 1913. Bollettino del Laboratorio di Zoologia Generale e Agraria della Reale Scuola Superiore d'Agricoltura. Portici 8: 179-186.
 * Emery, C.. "Catalogo delle formiche esistenti nelle collezioni del Museo Civico di Genova. Parte terza. Formiche della regione Indo-Malese e dell'Australia." Annali del Museo Civico di Storia Naturale Giacomo Doria (Genova) (2) 4, no. 24 (1887): 209-258.
 * Mohamed M. 1995. A preliminary list of ants (Hymenoptera: Formicidae) of the Tawau Hills Park, Sabah. In: Ghazally Ismail  et al.  (eds.),  Tawau  Hills Park,  Sabah,  Pelanduk Pub.  Pp.  205-213.