|Alliance:||Formicoxenus genus group|
(Species Checklist, Species by Country)
|Based on Ward et al. (2014) and Blaimer et al. (2018).|
These rare ants nest and forage arboreally and little is known about their biology. The few nests which have been found were in twigs.
- 1 Photo Gallery
- 2 Identification
- 3 Distribution
- 4 Biology
- 5 Castes
- 6 Morphology
- 7 Nomenclature
- 8 References
Mandible short-triangular, the masticatory margin with 5 teeth, uniquely arranged. The large apical tooth is followed by two smaller teeth (third smaller than second), then a long diastema and two small basal teeth. Length of diastema is at least equal to length of margin occupied by the apical group of three teeth. This dentition is autapomorphic and unique in the Myrmicinae. This character alone will instantly diagnose Vombisidris and separate it from all other genera in the subfamily.
The sides of the head behind the eyes have an elongate ridge or groove on each side which starts at the mandibles, runs the length of the head and ends near the upper corners, and touches the lower surface of the eye. In side view, the petiole has a distinct, arched node on its upper surface. This distinctive ridge/groove on the sides of the head behind the eyes combined with the high, arching petiolar node is also diagnostic and will separate these ants from all other ant genera.
Keys including this Genus
Keys to Species in this Genus
Eastern India to Queensland, Australia.
Distribution and Richness based on AntMaps
Hosoishi et al. (2015) collected colonies of Vombisidris sp. by nest sampling in a regrowth forest in Kampong Thom Province, Cambodia. In his revision of the genus, Bolton (1991) listed 12 species and provided a key to the species with descriptions. His collections did not include any Indochinese specimens. The specimens collected in this study were assigned to the Vombisidris philax group based on the following features: subocular groove complete; legs and antennae relatively long; propodeal spines long and downcurved; metanotal groove absent. Our specimens are similar to V. nahet (head width 0.66–0.68 mm, n = 2), but the body is relatively smaller (head width 0.50–0.55 mm, n = 4).
Life History Traits
- Mean colony size: 20-30 (Greer et al., 2021)
- Compound colony type: not parasitic (Greer et al., 2021)
- Nest site: arboreal (Greer et al., 2021)
- Diet class: herbivore (Greer et al., 2021)
- Foraging stratum: subterranean/leaf litter; arboreal (Greer et al., 2021)
Males have yet to be collected.
Worker of V. renateae from Queensland.
• Antennal segment count: 12 • Antennal club: 3 • Palp formula: 5,3 • Spur formula: 0, 0 • Eyes: >100 ommatidia • Pronotal Spines: absent • Mesonotal Spines: absent • Propodeal Spines: present • Petiolar Spines: absent • Caste: none or weak • Sting: present • Metaplural Gland: present • Cocoon: absent
• Caste unknown
The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.
- VOMBISIDRIS [Myrmicinae: Formicoxenini]
- Vombisidris Bolton, 1991: 1. Type-species: Vombisidris philax, by original designation.
Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.
Diagnosis of worker. Monomorphic terrestrial to arboreal myrmicine ants with the following combination of characters.
1. Palp formula 5, 3.
2. Mandible short-triangular, the masticatory margin with 5 teeth, uniquely arranged. The large apical tooth is followed by two smaller teeth (third smaller than second), then a long diastema and two small basal teeth. Length of diastema is at least equal to length of margin occupied by the apical group of three teeth.
3. Anterior clypeal margin lacking an isolated median seta; instead with a pair of setae that straddle the midpoint.
4. Median portion of clypeus broad posteriorly, broadly inserted between the frontal lobes.
5. Frontal lobes narrow, each lobe distinctly narrower than the portion of the clypeus which is inserted between them.
6. Torulus concealed by frontal lobes in full-face view, not freely projecting.
7. Frontal carinae and antennal scrobes absent.
8. Eyes of moderate size, at or slightly in front of the midlength of the sides of the head.
9. Antennae 12-segmented, with a strongly defined 3-segmented apical club.
10. Sides of head usually with a strong sinuate subocular groove; groove incomplete in two species (see second lug of key couplet 1).
11. Alitrunk elongate and low in profile; promesonotum not domed-convex; propodeum bispinose.
12. Propodeal spiracle high on side, at about midlength of sclerite. distinctly separated from the small metapleural gland bulla.
13. Metapleural lobes present, small and rounded.
14. Metasternal process absent.
15. Tibial spurs absent from middle and hind legs.
16. Petiole pedunculate. the spiracle located from very close to the ali trunk articulation to just behind the midlength of the peduncle.
17. Postpetiolar sternite reduced, small in profile.
18. First gastral tergite strongly overlapping the sternite; sternite with a laterobasal angular junction with the tergite or strongly overlapped throughout.
19. Sting functional, strong and simple.
20. Cuticle thick and armoured, sculpture variable. Pilosity present, moderately dense, the individual hairs usually short and often blunted. Scapes with long outstanding (erect to suberect) hairs at least on the leading edge.
Female - As worker but with ocelli and full complement of flight sclerites; winged when virgin. Females known only in Vombisidris bilongrudi, Vombisidris renateae, and Vombisidris australis, see Taylor (1989).
-  Bolton, B. 1991. New myrmicine genera from the Oriental Region (Hymenoptera: Formicidae). Syst. Entomol. 16: 1-13 (page 1, 2, Vombisidris in Myrmicinae, Leptothoracini; Key to species.)
- Blaimer, B.B., Ward, P.S., Schultz, T.R., Fisher, B.L., Brady, S.G. 2018. Paleotropical diversification dominates the evolution of the hyperdiverse ant tribe Crematogastrini (Hymenoptera: Formicidae). Insect Systematics and Diversity 2(5): 3; 1-14 (doi:10.1093/isd/ixy013).
- Bolton, B. 1994. Identification guide to the ant genera of the world. Cambridge, Mass.: Harvard University Press, 222 pp. (page 105, Vombisidris in Myrmicinae, Formicoxenini)
- Bolton, B. 2003. Synopsis and Classification of Formicidae. Mem. Am. Entomol. Inst. 71: 370pp (page 253, Vombisidris in Myrmicinae, Formicoxenini)
- Cantone S. 2018. Winged Ants, The queen. Dichotomous key to genera of winged female ants in the World. The Wings of Ants: morphological and systematic relationships (self-published).
- Kreider, J.J., Chen, T.W., Hartke, T.R., Buchori, D., Hidayat, P., Nazarreta, R., Scheu, S., Drescher, J. 2021. Rainforest conversion to monocultures favors generalist ants with large colonies. Ecosphere 12 (doi:10.1002/ecs2.3717).
- Shattuck, S. O. 1999. Australian ants. Their biology and identification. Collingwood, Victoria: CSIRO Publishing, xi + 226 pp. (page 172, Australia synopsis)
- Taylor, R.W. 1989. Australian ants of the genus Leptothorax Mayr (Hymenoptera: Formicidae: Myrmicinae). Memoirs of the Queensland Museum, 27: 605-610.