Opistophthalmus ater

Assessor: Ian Engelbrecht

Other assessors
Sarah Schumann
Sensitive in 2010
Reason for the sensitivity status
Species of this genus are known to be targeted, collected and traded in international and local exotic pet trade. They are easily bred in captivity and usually of wild origin. As this species has a vulnerable population size and produces low numbers of offspring, were over-harvesting to occur, recovery may be poor. Releasing data on this species can exacerbate threat and vulnerability.
This species is either similar to another sensitive species or belongs to a group containing sensitive species, and is extremely rare in the wild. The localities of wild populations need to be protected to avoid loss to exploitation, which, due to its rarity, could drive the species to extinction within a very short time.
Exploitation extent
Uncertain - No data exists yet showing that this species is exploited in the wild, however it has one or more relatives or look-alike species (found in South Africa or globally) that are known to be utilised. This species has a similar life form or other relevant traits to its exploited relative(s), making it highly likely that it would be exploited for the same purposes.
Justification and references

The burrowing scorpions of the genus Opistophthalmus are known to be harvested from the wild for trade and appear in the international and local exotic pet trade with some regularity (see websites listed below for examples) (Prendini, 2003). The primary species traded are O. glabrifrons and O. wahlbergii, which are desired for their large size, impressive appearance, relatively placid demeanor, and ease of care. These scorpions are easily bred in captivity and animals sold in the trade are almost always of wild origin. While the species discussed here is not reported from the pet trade, it may be targeted by hobbyist collectors with a special interest in the genus. However, it would appear that interest in the 'thin-tailed' scorpions (scorpionids and hormurids) has decreased since around a decade ago in favor of keeping thick-tailed scorpions of the family Buthidae (pers. obs.) as they are easier to care for and breed in general.

Prendini, L., Crowe, T.M. and Wheeler, W.C., 2003. Systematics and biogeography of the family Scorpionidae (Chelicerata: Scorpiones), with a discussion on phylogenetic methods. Invertebrate Systematics17(2), pp.185-259.

Population vulnerability
Population is vulnerable: size is <= 2500 mature individuals OR the number of known subpopulations is <= 5 OR range is <= 100km2 OR species at risk of localised extinctions
Justification and references

This species is known to occur only on a specific geology with a small aerial extent in the Northern Cape. The number of known localities is very small and limited to the outskirts of a nearby settlement, but recent sampling I undertook located the species further away on the same geology, suggesting it occupies the entire extent of the geological outcrop. Based on this the estimated Extent of Occurrence of approximately 100km2. 

The known distributions of scorpions are based on records published in Lamoral and Reynders (1975) and Prendini (1995), on ScorpionMap project on the ADU Virtual Museum, and on my own experience sampling scorpions across southern Africa for atlasing and taxonomic purposes. The estimate of the extent of occurrence for this species was prepared using Google Maps satellite imagery for identifying the extent of the geological formation it occupies, using an online area calculation tool available at https://www.daftlogic.com/projects-google-maps-area-calculator-tool.htm.

Lamoral, B.H. and Reynders S.C. 1975. A catalogue of the scorpions described from the Ethiopian faunal region up to December 1973. Annals of the Natal Museum 33: 489-576.

Prendini, L. 1995. Patterns of scorpion distribution in southern Africa: a GIS approach. Unpublished BSc (Hons.) Thesis. University of Cape Town, South Africa.

Targeted demographics
Regeneration potential
This species has a slow population growth rate, or the growth rate varies depending on habitat, and there is a poor chance the wild populations will recover from exploitation OR a collector might feasibly harvest the entire extant population removing the chance of subsequent recruitment.
Justification and references

This species is not specifically targeted for the pet trade and there is limited demand for specialized species like this. However, given the small geographic range, targeted sampling under the right conditions could impact individual subpopulations severely. While the population growth rate is unknown, there is evidence that small Opistophthalmus species such as this only produce small numbers of offspring (pers. obs.), which would mean population recovery rates would be low following extensive harvesting events.