Taxonomic Notes
The status of the name Garetta azureus remains extremely confused following two conflicting taxonomic revisions (Moretto and Génier 2015, Pokorný and Zídek 2018).
Moretto and Génier (2015) re-examined the type series of Ateuchtus azureus and concluded that the entire series represents the smaller-bodied Garetta nitens, while larger-bodied individuals that have been referred to by the name G. azureus belong to a distinct species, for which the oldest available name is Garetta laetus. They consequently synonymised A. azureus within G. nitens and revalidated G. laetus with two allopatric subspecies: G. l. laetus and G. l. olivaceus.
Pokorný and Zídek (2018) disagreed with this arrangement and accepted a valid Garetta azureus as a distinct species from G. laetus (which they regarded as monotypic) and G. nitens, following Janssens (1940).
Moretto and Génier (2015) also revalidated Garreta wahlbergi from synonymy with G. nitens on the basis of differing exoskeleton microsculpture. Pokorný and Zídek (2018) resyonymised G. wahlbergi, arguing that the difference in microsculpture merely represented intraspecific variation within G. nitens.
Davis et al. (2020) recommended a molecular analysis to support or overturn these arrangements, and accepted the arrangement of Moretto and Génier (2015) pending resolution of the taxonomy of this group. This approach is accepted by Schoolmeesters (2022) and is followed here.
Justification
Garreta nitens occupies a large distributional range and has been recorded on a wide range of dung types. It favours areas of open or dense woodland on finer-grained soils. However, this species is unlikely to be threatened at present as wide expanses of relatively untransformed woodland exist within its range, some of it within game reserves. Therefore, it is classed as being of Least Concern.
Geographic Range Information
As presently understood this species occurs in three widely disjunct distribution centres across tropical Africa. One occurs in northern Namibia and Angola, which may be genuinely isolated to the southwest of the megaKalahari sands reflecting the distribution of suitable moist habitats on fine-grained soils (Davis et al. 2020). Another ranges across the moister savanna zone through West, south Central, and East Africa. The third lies in Ethiopia and Eritrea (Davis et al. 2020). The countries of occurrence list follows Moretto and Genier (2015), with the addition of South Sudan (mapped but not listed by these authors), as well as Somalia (not mapped here) and Gambia (listed in Schoolmeesters 2022, and unaffected by taxonomic changes to southern populations). Reports from South Africa, Eswatini, Zimbabwe, and Botswana (listed in Schoolmeesters 2022) refer to Garetta wahlbergi (A. Davis pers. comm. 2023).
In northern Namibia, Zambia and Malawi the species has been recorded between 683 and 2,196 m. Elevations as low as 34 m asl (Davis 2013) include data for the former synonym Garetta wahlbergi (A. Davis pers. comm. 2023).
Population Information
There is no information on the population status of this species following taxonomic changes, although it is not uncommon in suitable habitat in northern Namibia (A. Davis pers. comm. 2023).
Habitat and Ecology Information
In Namibia, the qualitative collection records of this species exhibit a bias towards finer-grained soils (sandy loam and sandy clay loam) within savanna woodland, and occasionally shrubland (Davis et al. 2020). This suggests ecological preferences similar to those supported by stronger data for Garetta wahlbergi (A. Davis pers. comm. 2023). Dung records in this area are primarily from cattle, with smaller numbers from elephant and zebra (Davis et al. 2020). Across 26 localities in northern Namibia, Zambia, and Malawi mean annual rainfall ranges from 356 to 2,097 mm, but it exhibits an apparent preference throughout its range for moist areas (Davis et al. 2020). Based on the same data mean annual temperature is between 13.8 and 23.2 °C (Davis et al. 2020). It is flight-active by day during the summer rainy season (November to April) (Davis et al. 2020).
Threats Information
As this species may be a specialist in woody vegetation on finer-grained soils, as is the close relative G. wahlbergi (Davis 1996), the clearance of woodland that has occurred in wide areas of Africa is likely to be a localised threat, but may be partly offset by the widespread distribution of the species (Schoolmeesters 2011).
Use and Trade Information
There is no use or trade information available for this species.
Conservation Actions Information
There are no species-specific conservation measures in place, and none are required at present. This species has an extremely widespread distribution, which overlaps with a number of reserves (Davis et al. 2020). However, it is recommended that there should be a taxonomic review of the species and its varieties in relation to surveys of their ranges and habitat associations.