Aenictus montivagus

Aenictus montivagus
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Dorylinae
Genus:	Aenictus
Species:	A. montivagus
Binomial name
Aenictus montivagus Jaitrong & Yamane, 2011 Specimen Labels

Judging from the type series and non-type material examined this species inhabits highland forests (1000–1600 m alt.). Most colonies were encountered in the daytime.

Identification

A member of the laeviceps species group. This species is most similar to Aenictus hodgsoni in body shape but can be distinguished from it as follows: mesopleuron, metapleuron and propodeum entirely sculptured, with about 20 fine longitudinal rugulae, except for a small smooth area above the propodeal spiracle (dorsal face of propodeum more extensively smooth and shiny in the latter); subpetiolar process weakly developed and low (well developed and triangular in the latter); declivity of propodeum encircled with a very thin rim (declivity without a rim and seen from back tapering above in the latter); legs entirely smooth and shiny (femora extensively superficially reticulate and shiny, and tibiae very finely reticulate in the latter). (Jaitrong and Yamane 2011)

Keys including this Species

• Key to Aenictus laeviceps group species

Distribution

Distribution based on Regional Taxon Lists

Indo-Australian Region: Borneo, Indonesia, Malaysia (type locality).

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Explore Overview of Aenictus biology  Little is known about the biology of Aenictus montivagus. 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 Online Catalogue of the Ants of the World.

• montivagus. Aenictus montivagus Jaitrong & Yamane, 2011: 41, figs. 54-56 (w.) BORNEO (East Malaysia: Sabah).
  • Type-material: holotype worker, 20 paratype workers.
  • Type-locality: holotype Malaysia: Borneo, Sabah, Taman Kinabalu, 1500 m., 7.i.1998, SB98-SKY-05 (Sk. Yamane); paratypes: 8 workers with same data, 12 workers Sabah, Kinabalu Park, 1600 m., 6.ii.2001, SB01-SKY-03 (Sk. Yamane).
  • Type-depositories: MBSM (holotype); BMNH, SKYC, TNHM (paratypes).
  • Distribution: Malaysia (Sabah).

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

Description

Worker

Measurements. Worker holotype and paratypes (n = 9): TL 3.70–4.00 mm; HL 0.73–0.78 mm; HW 0.63–0.68 mm; SL 0.60–0.68 mm; ML 1.13–1.20 mm; PL 0.28–0.30 mm; CI 87–90; SI 92–100.

Holotype and paratypes - Head in full-face view longer than broad, with sides and posterior margin slightly convex; occipital carina complete. Antennal scape relatively short, extending only slightly beyond 2/3 of head length; antennal segments II–X each longer than broad; II almost as long as each of III–VI. Frontal carina very short, not extending beyond the level of posterior margin of torulus. Anterior margin of clypeus bearing 6–7 denticles. Masticatory margin of mandible with a large apical tooth followed by a medium-sized subapical tooth, 4 denticles and a medium-sized basal tooth; basal margin bearing 3–4 smaller teeth. Promesonotum in profile convex dosally; propodeum slightly lower than promesonotum, and its dorsal outline almost straight; propodeal junction roundly angulate; declivity of propodeum shallowly concave, encircled with a very thin rim. Petiole distinctly longer than high, dorsally weakly convex; subpetiolar process weakly developed and low, its apex directed downward; postpetiole distinctly shorter than petiole.

Head including mandible and antennal scape entirely smooth and shiny. Pronotum smooth and shiny, with its anteriormost portion punctate; mesothorax, metapleuron and propodeum entirely sculptured, the sculpture comprising ca. 20 fine longitudinal rugulae, but often with dense punctures; a small smooth area present near spiracle. Petiole and postpetiole entirely smooth. Legs entirely smooth and shiny.

Hairs on dorsa of head and pronotum more abundant than in other species; mesonotum and propodeum dorsally with several standing hairs; longest pronotal hair 0.23–0.25 mm long. Entire body dark reddish-brown. Typhlatta spot smaller than in other species, located anterior to occipital corner.

Type Material

Holotype worker from Borneo, Sabah, Taman Kinabalu, 1,500 m alt., 7 I 1998, Sk. Yamane leg., SB98- SKY-05 (UMS). Eight paratype workers, same data as holotype (The Natural History Museum, SKY Collection, Natural History Museum of the National Science Museum) and 12 paratype workers from Borneo, Sabah, Kinabalu Park, 1,600 m alt., 6 II 2001, Sk. Yamane leg., SB01-SKY-03 (SKYC, THNHM).

Etymology

The specific name is an adjective pertaining wondering in the mountain.

References

• 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.

References based on Global Ant Biodiversity Informatics

• Borowiec M. L. 2016. Generic revision of the ant subfamily Dorylinae (Hymenoptera, Formicidae). ZooKeys 608: 1–280.
• 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.