Ibala arcus

Ibala arcus
female
female
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Araneomorphae
Family: Gnaphosidae
Genus: Ibala
Species:
I. arcus
Binomial name
Ibala arcus
(Tucker, 1923)
Synonyms
  • Setaphis calviniensis Tucker, 1923

Ibala arcus is a species of spider in the family Gnaphosidae. It is a southern African endemic species.

Distribution

Ibala arcus is distributed across Zimbabwe, Namibia, and South Africa. In South Africa, it is recorded from all provinces at altitudes ranging from 47 to 1,645 m above sea level.

Habitat and ecology

The species is a free-living ground dweller, sampled from the Grassland, Nama Karoo, Savanna, and Succulent Karoo biomes. It has also been sampled from maize fields.

The species mimics velvet ants (Hymenoptera: Mutillidae) with whom they are often caught in pitfall traps.

Description

female

Ibala arcus is known from both sexes. It is a small spider with average total length of 4-6 mm. The carapace and legs are reddish brown, while the abdomen is black with four white spots dorsally joined to form two longitudinal white strips.

Conservation

Ibala arcus is listed as Least Concern by the South African National Biodiversity Institute due to its wide distribution range. The species is found in more than 10 protected areas.

Taxonomy

The species was originally described by Tucker in 1923 from Warmbaths in Limpopo as Setaphis arcus. It was revised by Fitzpatrick (2009).

References

  1. 1 2 Tucker, R.W.E. (1923). "The Drassidae of South Africa". Annals of the South African Museum. 19 (2): 321.
  2. ↑ "Ibala arcus (Tucker, 1923)". World Spider Catalog. doi:10.24436/2. Retrieved 25 September 2025.
  3. 1 2 3 4 5 6 7 8 9 10 Dippenaar-Schoeman, A.S.; Haddad, C.R.; Foord, S.H.; Lotz, L.N. (2021). The Gnaphosidae of South Africa. Part 2 (E-S). South African National Survey of Arachnida Photo Identification Guide. p. 15. doi:10.5281/zenodo.7197672. This article incorporates text available under the CC BY 4.0 license.