Aenictus fergusoni

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Aenictus fergusoni
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Dorylinae
Genus: Aenictus
Species: A. fergusoni
Binomial name
Aenictus fergusoni
Forel, 1901

Aenictus fergusoni casent0281962 p 1 high.jpg

Aenictus fergusoni casent0281962 d 1 high.jpg

Specimen Labels

Synonyms

Nothing is known about the biology of Aenictus fergusoni.

Identification

A member of the laeviceps species group.

Keys including this Species

Distribution

India, from the extreme south north to Darjeeling and Assam, thence SE to Burma and Java. This species is also most unusual in that it has been recorded from Great Nicobar Island, which is over 160 km from the nearest large land mass (Sumatra).

Distribution based on Regional Taxon Lists

Oriental Region: Bangladesh, India (type locality), Myanmar, Nicobar Island, Thailand, Vietnam.
Palaearctic Region: China.

Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

Biology

Little is known about the biology of Aenictus fergusoni. 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

Known only from the worker caste.

Wilson 1964 Army Ant fig 21-30

Nomenclature

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

  • fergusoni. Aenictus fergusoni Forel, 1901a: 473 (w.) INDIA. Senior synonym of karawaiewi, montanus, piltzi: Wilson, 1964a: 462.
  • hodgsoni. Aenictus fergusoni var. hodgsoni Forel, 1901a: 474 (w.) MYANMAR. Junior synonym of fergusoni: Wilson, 1964a: 462.
  • montanus. Aenictus fergusoni var. montanus Forel, 1901a: 474 (w.) INDIA. Junior synonym of fergusoni: Wilson, 1964a: 462.
  • piltzi. Aenictus fergusoni var. piltzi Forel, 1901a: 474 (w.) INDIA. Junior synonym of fergusoni: Wilson, 1964a: 462.
  • karawaiewi. Aenictus fergusoni var. karawaiewi Wheeler, W.M. & Chapman, in Wheeler, W.M. 1930g: 199 (diagnosis in key) (w.) no locality given. Junior synonym of fergusoni: Wilson, 1964a: 462.

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) - Syntypes: HW 0.67 mm, HL 0.76 mm, SL 0.72 mm; other HW's in this series 0.63-0.72 mm. Antenna 10-segmented. Mandibles typical. Clypeus feebly convex, entire, armed with about 12 teeth. Parafrontal ridge very short, only 0.08 mm. Occiput convex, lacking distinct collar. Propodeal junction approximately right-angulate. Subpetiolar process a rounded lobe surmounted by a thin, downward-projecting flange. Pilosity moderately abundant, long; length of longest pronotal hairs 0.25 mm.

Head shining. Pronotum shining; remainder of mesosoma microreticulate and opaque, with traces of a few longitudinal rugae. Pedicel wholly shining except for the shagreened and subopaque peduncles. Head bearing yellow "Typhlatta spots"; otherwise head and mesosoma dark reddish brown. Pedicel and gaster somewhat lighter, medium reddish brown.

Type Material

Type locality: Tranvancore, India

References

  • Forel, A. 1901a. Les Formicides de l'Empire des Indes et de Ceylan. Part VIII. J. Bombay Nat. Hist. Soc. 13: 462-477 (page 473, worker described)
  • 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
  • Wilson, E. O. 1964a. The true army ants of the Indo-Australian area (Hymenoptera: Formicidae: Dorylinae). Pac. Insects 6: 427-483 (page 462, senior synonym of hodgsoni, karawaiewi, montanus and piltzi)