Colobostruma unicorna

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

The only known nest was found in open sclerophyll under rocks in soil on slope of ridge, and in nests of Polyrhachis ammon and Pseudoneoponera mayri.

Identification

Shattuck (2000) - The raised frontal lobes and extreme lateral margins of the clypeus combined with a projection on the centre of the clypeus will readily separate this species from all others in the genus, including the similar Colobostruma bicorna.

Keys including this Species

Key to Australian Colobostruma Species

Distribution

Mid to southern coastal Queensland

Latitudinal Distribution Pattern

Latitudinal Range: -21.96667° to -29.25°.


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 unicorna. 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.

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Castes

Nomenclature

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

unicorna. Colobostruma unicorna Shattuck, in Bolton, 2000: 46, figs. 37, 48 (w.q.) AUSTRALIA.

Type Material

Paratype Specimen Labels

Holotype, worker, Mt. Coot-tha, Brisbane, Queensland, 300-800 ft, Australia, 29 October 1964, B.B. Lowery, Australian National Insect Collection; open scerophyll, under rocks in soil on slope of ridge, found in nests of Polyrhachis ammon and Pseudoneoponera mayri.
Paratype, 16 workers, 1 queen, Mt. Coot-tha, Brisbane, Queensland, 300-800 ft, Australia, 29 October 1964, B.B. Lowery, Australian National Insect Collection, The Natural History Museum, Museum of Comparative Zoology; open scerophyll, under rocks in soil on slope of ridge, found in nests of Polyrhachis ammon and Pseudoneoponera mayri.

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

Description

Worker

HOLOTYPE WORKER. TL 3.0, HL 0.70, HW 0.60, CI 86, ML 0.14, MI 20, SL 0.32, SI 53, PW 0.39, AL 0.80. Anterior region of head raised slightly above the posterior region and separated from it by a rounded angle, thus the head weakly but not obviously phragmotic. In full-face view ridge immediately in front of eye weakly concave. Frontal lobes immediately above the antennal insertions and the lateral margins of clypeus immediately above the mandibular insertions raised above the surrounding surface of the head; the centre of the clypeus with a distinct, raised pointed projection. Mandibles broadly triangular. Hairs absent from dorsum of head. Posterior margin of head deeply concave. Antenna with 5 or 6 segments, when 6-segmented the fourth funicular segment from the base is much shorter than the third segment. Scape weakly elbowed and without a subbasal lobe. In dorsal view the widest point of the pronotum is at the humeral angles. Propodeum high, its declivity approximately the same height as the petiolar node and with broad, thin lamellae; in profile the dorsum of the alitrunk flat with a weak convexity at the metanotal groove. Petiole with a broad, irregular ventral lamella. Lateral postpetiole drawn outwards into thin 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 smaller than the posterior windows. First gastral tergite with delicate reticulate sculpture which is stronger anteriorly and weaker posteriorly, the anterior one-third superimposed with low, closely spaced carinae. Body colour honey yellow, dorsum of head slightly darker.

References

Jansen, G., Savolainen, R. 2010. Molecular phylogeny of the ant tribe Myrmicini (Hymenoptera: Formicidae). Zoological Journal of the Linnean Society 160(3), 482–495 (doi:10.1111/j.1096-3642.2009.00604.x).
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 46, figs. 37, 48 worker, queen described)

References based on Global Ant Biodiversity Informatics

Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65