Colobostruma biconvexa

Colobostruma biconvexa
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Attini
Genus:	Colobostruma
Species:	C. biconvexa
Binomial name
Colobostruma biconvexa Shattuck, 2000 Specimen Label

This rare species is limited to coastal Queensland. It is limited to rainforest (or occasionally wet sclerophyll) and has so far only been found in leaf litter samples.

Identification

Shattuck (2000) - Colobostruma biconvexa is most similar to Colobostruma biconcava. C. biconcava differs in having the posterior faces of the petiole and postpetiole weakly concave, whereas these faces are convex in biconvexa. Additionally, biconcava is known from the Australian Capital Territory and South Australia while biconvexa is known only from Queensland.

Keys including this Species

• Key to Australian Colobostruma Species

Distribution

Known only from Queensland.

Latitudinal Distribution Pattern

Latitudinal Range: -15.48333333° to -27.5°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Australasian Region: Australia (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 Colobostruma biology  Beyond what is stated in the introduction at the top of this page, little is know about the biology of Colobostruma biconvexa. Until further studies reveal more about this species we can infer that its natural history and biology should be similar to other species in this genus. In general Colobostruma can be locally common although they are often overlooked. Most species have small colonies with less than 100 workers, and workers will lie motionless when disturbed. Nests can occur in soil usually under rocks, in cracks in rocks or in rotten logs. Only a single rainforest species is known to nest arboreally. Foraging is usually on the ground at night but occasionally they are found foraging on mallee. They are also commonly found in leaf litter. ‎

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

• biconvexa. Colobostruma biconvexa Shattuck, in Bolton, 2000: 35 (w.q.) AUSTRALIA (Queensland).
  • Type-material: holotype worker, 11 paratype workers, 1 paratype queen.
  • Type-locality: holotype Australia: Queensland, Mt Cook Nat. Park, 15°29’S, 145°16’E, 10-12.v.1981, rainforest, litter (berlesate) (A. Calder & J.E. Feehan); paratypes with same data.
  • Type-depositories: ANIC (holotype); ANIC, BMNH, MCZC (paratypes).
  • Distribution : Australia.

Type Material

• Holotype, worker, Mt Cook National Park, Queensland, Australia, 15°29′N 145°16′E, 10-12.v.1981, Calder,A. & Feehan,J., ANIC32-015701, Australian National Insect Collection; rainforest, litter (berlesate).
• Paratype, 11 workers, 1 queen, Mt Cook National Park, Queensland, Australia, 15°29′N 145°16′E, Australian National Insect Collection, The Natural History Museum or Museum of Comparative Zoology.

Description

Worker

HOLOTYPE WORKER. TL 2.1, HL 0.52, HW 0.48, CI 92, ML 0.13, MI 25, SL 0.28, SI 58, PW 0.29, AL 0.55. Anterior region of head rounding gradually from the dorsal to lateral surfaces, not phragmotic. In full-face view ridge immediately in front of eye weakly concave. Frontal lobes and lateral margins of the clypeus smooth and relative to the surrounding surface of the head. Mandibles broadly triangular. Hairs absent from dorsum of head. Posterior margin of head shallowly concave, the medial region nearly flat. Antenna generally 4-segmented, when 5-segmented the third funicular segment from the base much shorter than the second segment; the second segment approximately one-third longer than the first segment. Scape elbowed and without a subbasal lobe. In dorsal view the widest point of the pronotum is at the humeral angles. Propodeum high, its posterior face greater in height than the petiolar node and with broad, thin lamellae; in profile the dorsum of the alitrunk nearly flat to gently and weakly arched. Lateral postpetiole drawn outwards into the flange-like wings, the wings with translucent windows along both their anterior and posterior margins, the windows separated by a narrow band of thickened integument, the anterior windows reduced to narrow bands along the leading edge. Posterior faces of the petiole and postpetiole convex. First gastral tergite superimposed with weakly defined reticulate sculpturing, its anterior one-quarter with a series of low longitudinal carinae. Body colour uniform honey yellow, the gaster sometimes with a complete or incomplete, weakly infuscated medial band.

References

• Shattuck, S. O. 2000. Genus Colobostruma. Genus Mesostruma. Genus Epopostruma. Pp. 31-67 in: Bolton, B. The ant tribe Dacetini. Mem. Am. Entomol. Inst. 65: 1-1028 (page 35, worker, queen described)

References based on Global Ant Biodiversity Informatics

• Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
• Osunkoya O. O., C. Polo, and A. N. Andersen. 2011. Invasion impacts on biodiversity: response of ant communities to infestation by cat's claw creeper vine, Macfadyena unguis-cati (Bignoniaceae) in subtropical Australia. Biol. Invasions 13: 2289-2302.