Rüppell's Parrot Poicephalus rueppellii was until recently considered to be a monotypic species. Birds from parts of north-western and west-central Angola, however, differ significantly in colour and size from the better-known populations across the rest of their range, which fact was overlooked until very recently. Because the name rueppellii was originally applied to the less-known Angolan population, it was the commoner southern population that lacked a taxonomic identity. The latter was described as Poicephalus rueppellii mariettae Hubers & Schnitker, 2022.
Rüppell's Parrot Poicephalus rueppellii (G. R. Gray, 1849) is a medium-sized dusky-brown parrot with the carpal joint, leading edge of the wing and underwing-coverts bright yellow. Remarkably, adult females are more colourful than adult males (see Appendix) as they also have a blue rump and lower belly. The species occurs in southwest Angola, north as far as Luanda (e.g., Bannerman 1912, eBird 2021) to north and central Namibia as far south as Sesriem (eBird 2021). Within this range the species is widely distributed in Namibia, extending into south-west Angola in Namibe, but there are only a few isolated populations elsewhere in Angola, mainly around the towns of Benguela and Luanda (Fig. 1). In southern Angola and Namibia the species is well known, whereas knowledge of the northwest and west-central Angolan populations is scarce and there are very few specimens in collections (see below).
The species has long been considered monotypic. Many sources (e.g., Collar 1997, Dickinson & Remsen 2013) do not clearly mention the populations in northwestern and west-central Angola. Based on specimens in the Natural History Museum, Tring (NHMUK) we have found that there are two distinctive morphotypes that differ significantly in colour and size. Fry et al. (1988) already noted that birds in Angola are smaller but did not mention the difference in colour.
Figure 1.
Distribution map of Rüppell's Parrot Poicephalus rueppellii based on e-Bird ( https://ebird.org/species/ruepar1?siteLanguage=de). P. r. rueppellii (red dots) occurs only in north-west and west-central Angola around Luanda and Benguela, whereas P. r. mariettae (green dots) is widespread in Namibia and south-west Angola (© Thomas Arndt)
Figure 2.
Differences in the blue coloration of females of the two subspecies of Rüppell's Parrot Poicephalus rueppellii. Left-hand bird in both A and B, P. r. rueppellii from northern Angola (NHMUK 1890.4.1.21, died 7 June 1882 at London Zoo, see also Fig. 7) and right P. r. mariettae from Namibia (NHMUK 1852.5.1.16, collected by C. J. Andersson in 1850 in Namibia, see Fig. 6) (Jonathan Jackson, © Natural History Museum, London)
We found that specimens from Angola (except the south-west) are generally smaller (wing length in adults, n = 5: 132–140 mm) with on average darker overall plumage, and the blue rump and lower belly in females is significantly paler (turquoise-blue) compared to birds from Namibia and south-west Angola (Fig. 2). These latter are generally larger (wing length in adults, n = 9: 142–155 mm) with on average paler-coloured plumage, but the blue in females is significantly darker, more ultramarine. Photographs of birds in the wild confirm the differences in colour (Figs. 3–4). We also found five other specimens from north-west and west-central Angola with the same characteristics—smaller, generally darker and more turquoise-blue—in other institutions: three in the Naturalis Biodiversity Center, Leiden (RMNH.AVES.209654, see Fig. 5, and ZMA.AVES.944 and ZMA.AVES.945, the last two formerly held at the Zoölogisch Museum Amsterdam), one in the Senckenberg Museum Frankfurt (SMF 26.604) and one in the Instituto de Investigação Científica de Angola, Luanda (IICA 4301).
In the original description, Gray (1849) noted that the holotype came from the ‘river Nunez'. Although this wording does not appear on the specimen’s label, it has been taken by many authors to be the type locality for P. rueppellii. This river, however, is in present-day Republic of Guinea and therefore is well north of the species' range in Angola and Namibia. Peters (1937) realised the problem and altered the type locality to ‘Damaraland’. Later, MacDonald (1957) restricted it to the ‘Swakop River, Damaraland, Namibia’, thereby linking (inadvertently) the name rueppellii to southern populations of larger and paler birds. However, Gray’s holotype of P. rueppellii, a male held at NHMUK, clearly belongs to the northern morphotype. It is relatively small (wing length 135 mm) and dark in overall colour. Furthermore, its label is inscribed ‘West-Africa’, which term was then applied to an even wider area than today including present-day Angola, and therefore, unlike the original description, does not mention’river Nunez’ as its provenance. Consequently, the epithet rueppellii must be assigned to the smaller, darker northern taxon, which as far as is known occurs only around the towns of Benguela and Luanda in Angola. As a result, we propose to restrict the type locality to ‘Luanda’, after the shared locality of the only two specimens at NHMUK with precise data in this respect (NHMUK 1911.12.18.146, St. Paul de Loanda, and NHMUK 1911.12.18.147; Bemfica, Morro de Cruz, near Luanda; see also Bannerman 1912: 250).
Figure 3.
Rüppell's Parrot Poicephalus r. rueppellii from north-west and west-central Angola; note the turquoise-blue plumage in females. (A) adult female, near Luanda, 16 September 2019 (© David & Sara Elizalde); (B) adult female, Mirador la Lua, Luanda province, 24 August 2012 (© Tommy P. Pedersen)
Figure 4.
Female of the recently described Poicephalus rueppellii mariettae, Namibia, 4 March 2018; this taxon, with dark ultramarine-blue plumage in females, is better known and more widespread than the nominate subspecies (© Charles James Sharp)
Figure 5.
Specimen of nominate Rüppell's Parrot Poicephalus rueppellii from north Angola, in the Naturalis Biodiversity Center, RMNH.AVES.209654, which is smaller and overall darker but has the blue rump and belly paler than birds from south-west Angola and Namibia (© Naturalis Biodiversity Center, Leiden)
Figure 6.
Type material of Poicephalus rueppelliimariettae, from left to right (in both A and B): holotype, adult female, NHMUK 1889.1.20.647; paratypes, adult male, NHMUK 1878.12.31.502, and juvenile, NHMUK 1878.12.31.431, all from Otjimbingwe, Damaraland, Namibia (Jonathan Jackson, © Natural History Museum, London)
Because the larger paler form common across the rest of the species' range lacked an available name, Hubers & Schnitker (2022) described the Namibian and south-west Angolan populations as Poicephalus rueppellii mariettae. They designated an adult female, NHMUK 1889.1.20.647, from Otjimbingwe, Damaraland, Namibia, as its holotype, with two paratypes, NHMUK 1878.12.31.502 (adult male) and NHMUK 1878.12.31.431 (juvenile, see Fig. 6) from the same locality. The name mariettae honours Jos Hubers' wife, Mariëtte.
The original description was published in German (Hubers & Schnitker 2022) with photos of specimens of both subspecies held in Tring, of females of both subspecies in the wild as well as of mariettae in captivity, and a map showing the two subspecies' known distributions including data from eBird (2021).
Figure 7.
Illustration (pl. V) in Gray's (1848) original description of Rüppell's Parrot Poicephalus rueppellii, based on the holotype (NHMUK 1855.12.19.362) from northern Angola (© Jonathan Jackson, Natural History Museum, London)
Figure 8.
Bird specimens collected by C. J. Andersson in 1850 in Damaraland (Namibia) were sold by the dealer A. D Bartlett of London and some were acquired by the British Museum, including this male (NHMUK 1852.5.1.15), on left in A and B, and female (NHMUK 1852.5.1.16) Rüppell's Parrot Poicephalus rueppellii mariettae. These specimens were seen by Strickland & Sclater (1852) and, because Andersson had not sexed the birds during preparation, due to the differences in colour it was assumed that the more colourful individual was the male (Jonathan Jackson, © Natural History Museum, London)
Figure 9.
Three of the four specimens received alive at London Zoo in April 1882 and which died in June 1882, from left to right: male, NHMUK 1890.4.1.19; male, NHMUK 1890.4.1.20; female, NHMUK 1890.4.1.21 (Jonathan Jackson, © Natural History Museum, London)
Figure 10.
Pl. XLII in Sclater (1882): the bird illustrated was one of two females received by London Zoo in April 1882 from northern Angola, and has the blue rump characteristic of female Rüppell's Parrot Poicephalus rueppellii but which is paler in colour than that of Namibian parrots, a fact Sclater failed to notice (Jonathan Jackson, © Natural History Museum, London)
Acknowledgements
We thank our reviewers, Lincoln Fishpool, R. J. Dowsett and an anonymous referee, for their constructive comments on the submitted manuscript. We also thank the following: Jonathan Jackson (Natural History Museum, London), Dr Gerald Mayr (Senckenberg Museum, Frankfurt am Main), Pepijn Kamminga (Naturalis, Leiden), Dr Fernanda Lages (Instituto de Investigação Científica de Angola, Luanda), David & Sara Elizalde, Tommy P. Pedersen and Charles James Sharp for information and / or photographs used herein.
References:
Appendices
Appendix: male or female?
In addition to having been, until recently, considered monotypic, colour differences between the sexes of Rüppell's Parrot Poicephalus rueppellii were a source of confusion for some time after the species' description. Until 1882 the bird described and pictured by Gray (1849, see Fig. 7) was assumed to be female (Sclater 1882). Strickland & Sclater (1853) had seen specimens from ‘Damaraland’ (Namibia) collected by Andersson (Fig. 8) and it was assumed that the more colourful bird, with a blue rump and belly, was male and the uniform individuals were female. Some authors (e.g., Hartlaub 1857) agreed but others (e.g., Schlegel 1864, Finsch 1868, du Bocage 1881) thought both sexes had blue feathers. Andersson himself (1872) had noted that only some females had blue feathers.
In April 1882 the Zoological Society of London received four live Rüppell's Parrots from ‘West Africa’, two with and two without blue feathering (Salvin 1882). These died c.2 months later and during dissection it was noticed that the blue-feathered birds were, in fact, female and the others were male (Sclater 1882). At least three of the specimens were initially retained in the Society’s collection but transferred to the then British Museum (Natural History) in 1891 (Fig. 9). Sclater (1882), the Society’s secretary at the time, noted that ‘exactly contrary to the usual state of the case, it is the female in Poicephalus rueppellii (Pl. XLII [Fig. 10]) that acquires this additional ornamental colour, and not the male.’
So, it was Sclater (1882) who was first to notice that female Rüppell's Parrot was more colourful than the male. What Sclater did not see was the difference in size and colour between the parrots received in 1882 and those collected by Andersson in Namibia that he had examined years earlier. The blue in the latter was much darker than that of the birds that died in the Society's Menagerie (= London Zoo) and were collected in ‘West Africa’ (= Angola, see Figs. 3 and 9). These were of the same morphotype as Gray’s (1849) holotype of rueppellii but the differences from the commoner and more widespread Namibian population went unnoticed for 137 years.
