Capricious subspeciation in the plains zebra, part 2: introducing the endangered Gorongosa zebra, Equus quagga foai

(writing in progress) 

...continued from https://www.inaturalist.org/journal/milewski/56214-capricious-subspeciation-in-the-plains-zebra-part-1#

The plains zebra (Equus quagga) was first discovered by Science in the eighteenth century. From the start, the conservation of the many and various subspecies of this widespread species has been hindered by a labelling failure.

This problem has continued until today - despite the sophisticated methods of modern taxonomy.

Equus quagga quagga was originally abundant and fairly widespread in South Africa. However, it was unwittingly hunted to extinction, because of an assurance that there remained plenty of 'kwaggas' farther north, across the Vaal River (https://en.wikipedia.org/wiki/Vaal_River). Unbeknownst to landowners, the 'kwagga' north of what is now Free State province (https://en.wikipedia.org/wiki/Free_State_(province)) was a different subspecies - so different, indeed, that it might as well be a different species.

Had the extinct quagga (https://en.wikipedia.org/wiki/Quagga) been given a more precise name, this nomenclatural confusion - and the biological tragedy caused by it - might have been avoided.

This is, indeed, why the quagga (E. q. quagga) was allowed to slip into extinction when other sympatric ungulates (e.g. black wildebeest) were saved. Because ‘kwaggas’ were still known to be abundant farther north in South Africa, nobody saw E. q. quagga for the distinctive form that it was, until it was too late. Actually, much too late (it was decades after extinction that anyone woke up to the loss).

One particular form has posed a taxonomic puzzle for many years.

I have, for the last half-century, recognised the intensely-striped zebra of Gorongosa National Park (https://hfmoconservationandscience.weebly.com/education-ecology-and-conservation/the-history-and-biodiversity-of-the-gorongosa-national-park and https://en.wikipedia.org/wiki/Gorongosa_National_Park) as something distinct.

Although Equus quagga crawshayi, of eastern Zambia, Malawi, and northern Mozambique has narrow stripes, the Gorongosa zebra has stripes that are even narrower, while retaining bold definition (https://www.flickr.com/photos/zimbart/38718489444).

Although fairly frequently photographed in Gorongosa National Park in the 'sixties and 'seventies, the Gorongosa zebra was virtually exterminated in that Park during the Mozambican Civil War. (https://en.wikipedia.org/wiki/Mozambican_Civil_War).

However, until now I have assumed that the Gorongosa zebra has never been given a scientific name that we can use to designate it as a particular subspecies of the plains zebra (Equus quagga).
 
As you can understand, it’s hard to push for the conservation of a critically endangered taxon that has no name. People tend not to take it seriously if it’s not labelled clearly.
 
Prazak and Trouessart in 1899 (Bull.Mus.Paris, 5:350, 1899) described an extremely intensely striped form from Mozambique as ‘foai’, so I think there’s a good chance that the Mozambique zebra can validly be called Equus quagga foai.

The type locality of what they described as a distinct species, Equus foai, is "the mountainous district of Angoniland, on the north bank of the Zambezi opposite Teti". See the location in https://en.wikipedia.org/wiki/Tete,_Mozambique.

Lydekker (1916, Catalogue of Ungulate Mammals in the British Museum) says that it is distinguished by "the larger number of main stripes on the body and hindquarters, and the absence of any backward bending (except in the last of the series) of the body stripes as they approach the dorsal stripe, to which they run approximately at right angles. In this respect Foa's zebra approximates to the true zebra and Grévy's zebra, from both of which it differs by the stripes on the hindquarters adjacent to the dorsal stripe running parallel with the latter in the direction of the tail…" 
 
The hide specimen shown below certainly belongs to the Mozambique zebra, and it’s the first such picture I’ve ever seen. It would make a good illustration for any item we post on EB on the topic of the Mozambique zebra, not so?

Something I have not noticed before: the striping is so intense on the posterior part of the dorsal area, or the anterior rump, that it forms a virtual spotting of pale on a ‘ground-colour’ of dark! I’ve never seen that in any other type of zebra. It is a noteworthy feature because it

• transcends striping to the point of qualifying as spotting, and
• inverts the normal relationship of dark and pale in this species.

http://www.planet-mammiferes.org/Photos/Ongule/Equides/EquuBFoa.jpg

http://www.planet-mammiferes.org/drupal/en/node/64?choixzone=&input2=Eastern+Africa&plus=0&fin=3
  
The hide specimen shown below certainly belongs to the Gorongosa zebra, and it is the first such picture I have ever seen.
 
(writing in progress)

Posted on July 13, 2022 10:29 AM by milewski