Aenictus peguensis

Every Ant Tells a Story - And Scientists Explain Their Stories Here
Jump to navigation Jump to search
Aenictus peguensis
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Dorylinae
Genus: Aenictus
Species group: minutulus
Species: A. peguensis
Binomial name
Aenictus peguensis
Emery, 1895

Aenictus peguensis casent0281968 p 1 high.jpg

Aenictus peguensis casent0281968 d 1 high.jpg

Specimen Labels

No biological information is available for A. peguensis. However, judging from the type locality and the locality of non-type material examined this species inhabits lowlands.

Identification

A member of the minutulus species group. Jaitrong and Yamane (2011) - Aenictus peguensis is most similar in general appearance to Aenictus subterraneus but is distinguished from the latter as follows: distinctly larger than the latter (total length 2.95–3.25mm, head width 0.52–0.60mm in A. peguensis; total length 2.10–2.15mm, head width 0.48–0.50mm in the latter); propodeal junction angulated, right-angled (roundly angulated in the latter); with head in full-face view posterior margin convex (feebly concave in the latter).

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Oriental Region: India, Myanmar (type locality), Vietnam.


Distribution based on AntMaps

AntMapLegend.png

Distribution based on AntWeb specimens

Check data from AntWeb

Biology

Little is known about the biology of Aenictus peguensis. 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.

Nomenclature

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

  • peguensis. Aenictus peguensis Emery, 1895k: 452 (w.) MYANMAR. Subspecies of ceylonicus: Forel, 1901a: 477. Revived status as species: Bingham, 1903: 22. See also: Wilson, 1964a: 472; Jaitrong & Hashimoto, 2012: 38.

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

Wilson 1964 Army Ant fig 31-36

Description

Worker

Jaitrong and Hashimoto (2012) - Measurements. Lectotype: TL 3.25 mm; HL 0.73 mm; HW 0.60 mm; SL 0.48 mm; ML 1.00 mm; PL 0.23 mm; CI 83; SI 79. Paralectotypes (n = 5): TL 2.95–3.15 mm; HL 0.60–0.70 mm; HW 0.52–0.58 mm; SL 0.40–0.45 mm; ML 0.88–0.95 mm; PL 0.20–0.23 mm; CI 82–96; SI 74–79.

Lectotype and paralectotypes - Head in full-face view slightly longer than broad, with convex sides and feebly convex posterior margin; occipital margin bearing a carina. Antennal scape reaching midlength of head; antennal segments II–X each longer than broad; II and III slenderer than IV–VI; terminal segment almost as long as VII+VIII+IX and 2.4 times as long as broad. Frontal carina short, posteriorly fused to form a single carina, slightly extending beyond the level of posterior margin of torulus. Masticatory margin of mandible with a large apical tooth followed by a medium–sized subapical tooth, 5–6 denticles, and a medium-sized basal tooth; basal margin with 4–5 small denticles. Promesonotum in profile strongly convex dorsally and sloping gradually to metanotal groove; metapleural gland bulla relatively small and transparent; distance between propodeal spiracle and metapleural gland bulla clearly longer than spiracular diameter (Fig. 5E). Propodeum in profile with convex dorsal outline; propodeal junction right-angled; declivity of propodeum seen from back convergent above. Petiole excluding subpetiolar process shorter than high, with its dorsal outline convex; subpetiolar process rather developed, with a sharply pointed lamellate appendage directed downward. Postpetiole clearly shorter than petiole, its dorsal outline convex.

Head including mandible and antennal scape smooth and shiny; basal portion of scape finely sculptured. Entire pronotum smooth and shiny except for its anteriormost portion punctate; mesothorax, petiole, and postpetiole entirely punctate but metapleuron at least partly impunctate. Legs entirely smooth and shiny. Head and mesosoma dorsally with relatively sparse standing hairs mixed with sparse short hairs over the surface; longest pronotal hair 0.18–0.23 mm long. Head, pronotum and gaster yelwish-brown; methothrax, propodeum, waist darker and often slightly reddish.

Type Material

References

  • Bingham, C. T. 1903. The fauna of British India, including Ceylon and Burma. Hymenoptera, Vol. II. Ants and Cuckoo-wasps. London: Taylor and Francis, 506 pp. (page 22, revived status as species)
  • Emery, C. 1895m. Viaggio di Leonardo Fea in Birmania e regioni vicine. LXIII. Formiche di Birmania del Tenasserim e dei Monti Carin raccolte da L. Fea. Parte II. Ann. Mus. Civ. Stor. Nat. 34[=(2(14): 450-483 (page 452, worker described)
  • Forel, A. 1901a. Les Formicides de l'Empire des Indes et de Ceylan. Part VIII. J. Bombay Nat. Hist. Soc. 13: 462-477 (page 477, subspecies of ceylonicus)
  • Jaitrong, W. & Hashimoto, Y. 2012. Revision of the Aenictus minutulus species group (Hymenoptera Formicidae Aenictinae) from Southeast Asia. Zootaxa 3426, 29-44.
  • Wilson, E. O. 1964a. The true army ants of the Indo-Australian area (Hymenoptera: Formicidae: Dorylinae). Pac. Insects 6: 427-483 (page 472, see also)