Aenictus camposi

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Aenictus camposi
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Dorylinae
Genus: Aenictus
Species: A. camposi
Binomial name
Aenictus camposi
Wheeler, W.M. & Chapman, 1925

Aenictus-camposiHolotypeL4x.jpg

Aenictus-camposiHolotypeD4x.jpg

Type Specimen Label

This species is found from lowland to highland and in natural and disturbed forests. Rosciszewski and Maschwitz (1994) reported that A.camposi fed on other small ant species such as five species of Paratrechina and Prenolepis naoroji in Pasoh Forest Reserve. Malay Peninsula. (Jaitrong et al. 2010)

The type series was collected from a bivouac beneath the bark of a fallen tree.

Identification

Jaitrong et al. (2010) - A member of the wroughtonii group. Aenictus camposi is most similar to Aenictus biroi (see under A. biroi) and Aenictus vieti. It is easily distinguished from A. vieti as follows: the declivity of propodeum is broader with more rounded apex in A. vieti (narrower and distinctly tapering above in A. camposi); subpetiolar process with anteroventral corner acutely angulate in A. vieti (unarmed in A. camposi).

Keys including this Species

Distribution

Aenictus camposi ranges from the Philippines through Sundaland to southern part of continental Southeast Asia.

Distribution based on Regional Taxon Lists

Indo-Australian Region: Borneo, Indonesia, Malaysia, Philippines (type locality).
Oriental Region: Thailand.
Palaearctic Region: China.

Check distribution from AntMaps.

Distribution based on specimens

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The above specimen data are provided by AntWeb. Please see Aenictus camposi for further details

Biology

Wheeler and Chapman (1930) report a number of workers were taken at Dumaguete from a small colony that was foraging in the open on the ground.

Little is known about the biology of Aenictus camposi. The genus is comprised of species that live an army ant lifestyle. Aenictus typically prey on other ants, from other genera, or other insects such as wasps or termites. There are reports of Aenictus preying on other insects as well and even have been observed collecting honeydew from homopterans (Santschi, 1933; Gotwald, 1995) but this appears, at least from available evidence, to be uncommon. Foraging raids can occur day or night across the ground surface. Occasionally raids are arboreal. During a raid numerous workers attack a single nest or small area, with several workers coordinating their efforts to carry large prey items back to the nest or bivouac. Aenictus have a nomadic life style, alternating between a migratory phase in which nests are temporary bivouacs in sheltered places above the ground and a stationary phase where semi-permanent underground nests are formed. During the nomadic phase bivouacs move regularly, sometimes more than once a day when larvae require large amounts of food. Individual nests usually contain up to several thousand workers, although nest fragments containing only a few hundred workers are often encountered. Queens are highly specialised and look less like workers than in most ant species. They have greatly enlarged gasters (dichthadiform) and remain flightless throughout their life. New colonies are formed by the division of existing colonies (fission) rather than by individual queens starting colonies on their own.

Castes

Male

Wilson 1964 Army Ant fig 58-63

Nomenclature

The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • camposi. Aenictus camposi Wheeler, W.M. & Chapman, 1925: 48, pl. 1, figs. 3, 4 (w.) PHILIPPINES. See also: Wilson, 1964a: 452; Jaitrong, et al. 2010: 38.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Description

Worker

Wilson (1964) - Syntype: HW 0.43 mm, HL 0.58 mm, SL 0.59 mm. Antenna 10-segmented. Mandible typical in form. Clypeus feebly convex, entire, dentate. Parafrontal ridge distinct but only 0.1 mm long. Propodeal junction acutely angulate. Subpetiolar process a low, right-angular lobe projecting anteriorly. Pilosity overall sparse, longest pronotal hairs only about 0.10 mm long.

Head smooth and shining. Mesosoma smooth and shining except for mesopleuron and propodeum, which are microreticulate and feebly shining. Also, there are short longitudinal rugae distributed along the propodeal junction. Concolorous clear yellow.

Jaitrong et al. (2010) - (10 non-type workers): TL 2.6-2.7 mm; HL 0.55-0.58 mm; HW 0.43-0.45 mm; SL 0.55-0.58 mm; ML 0.85-0.88 mm; MTL 0.55-0.58 mm; PL 0.25-0.28 mm; CI 74-82: SI 122-135.

Head in full-face view clearly longer than broad, with its sides and posterior margin slightly convex. Antennal scape long, extending beyond posterior corner of head; antennal segment II slightly shorter than III, but longer than each of IV-VI; the last (X) almost as long as VIII and IX combined and as long as II and III combined. Frontal carina short, thin and not extending beyond the level of posterior margin of torulus. Clypeus short, with its anterior margin bearing 5-7 denticles. Mandible with the apical tooth large and curved followed by 10-12 minute teeth on masticatory margin. Mesosoma in profile with pronotum convex dorsally and sloping gradually to metanotal groove. Propodeum in profile lower than promesonotum, with nearly straight dorsal outline; propodeal junction angulate; declivity of propodeum seen from back distinctly tapering above shallowly concave and encircled with a thin rim. Petiole in profile slightly longer than high, with the dorsal outline rather flat, seen from above relatively narrow, almost parallel-sided: subpetiolar process present with its ventral outline convex, without angle or tooth: postpetiole slightly smaller than petiole: its node short, almost as long as broad, in profile elevated posteriorly.

Head, antennal scape, pronotum, petiole, postpetiole, gaster, femora and tibiae of legs entirely or extensively smooth and shiny. Antennal flagellum densely punctate. The anteriormost portion of pronotum punctate: mesothorax and propodeum with dense punctures; metapleuron partly or extensively smooth: propodeal dorsum with short longitudinal rugae along the angle.

Body with relatively sparse standing hairs mixed with sparse short hairs over the surface; length of the longest pronotal hair 0.10-0.13 mm. Head, waist, gaster, antenna and legs yellow, mesosoma pale brown.

Type Material

Jaitrong et al. (2010) - Six syntypes on three pins (one on a pin, two on another, three on the other) from Horns of Negros, 1,200 m alt., Dumaguete, Oriental Negros Province, Philippines (Museum of Comparative Zoology, examined). The single specimen mounted on one pin is selected as the lectotype, the others as paralectotypes.

Determination Clarifications

Jaitrong et al. (2010) - Zhou (2001) recorded this species from Guangxi and some other provinces in China. However, according to his figs. 82 and 83 it is most probably Aenictus vieti.

References

  • Chapman, J. W.; Capco, S. R. 1951. Check list of the ants (Hymenoptera: Formicidae) of Asia. Monogr. Inst. Sci. Technol. Manila 1: 1-327 (page 11, checklist)
  • Jaitrong, W., Yamane, S. & Wiwatwitaya, D. 2010. The Army Ant Aenictus wroughtonii and related species in the Oriental region, with descriptions of two new species. Japanese Journal of Systematic Entomology 16: 33-36. PDF
  • Jaitrong, W. & Yamane, S. 2011. Synopsis of Aenictus species groups and revision of the A. currax and A. laeviceps groups in the eastern Oriental, Indo-Australian, and Australasian regions (Hymenoptera: Formicidae: Aenictinae). Zootaxa, 3128, 1–46. PDF
  • Wheeler, W. M. (1930) Philippine ants of the genus Aenictus with descriptions of the females of two species. Journal of the New York Entomological Society, 38, 193–212.
  • Wheeler, W. M.; Chapman, J. W. 1925. The ants of the Philippine Islands. Part I, Dorylinae and Ponerinae. Philipp. J. Sci. 28: 47-73 (page 48, pl. 1, figs. 3, 4 worker described)
  • Wilson, E. O. 1964a. The true army ants of the Indo-Australian area (Hymenoptera: Formicidae: Dorylinae). Pac. Insects 6: 427-483 (page 452, see also)