An attempted photo-guide to the subspecies of the steenbok (Raphicerus campestris) is partly a self-refuting exercise

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Today, I set out to illustrate - in the spirit of a field guide-book - the various subspecies of the steenbuck (Raphicerus campestris, https://www.inaturalist.org/taxa/42375-Raphicerus-campestris).

I was only partly successful, and this was not because of a lack of photos on the Web

Something important to realise, which has not emerged in the literature, is the following.

The northern subspecies (https://www.awl-images.com/stock-photo-kenya-taita-taveta-county-tsavo-east-national-park-a-steinbuck-image00398991.html) is only slightly different from the subspecies found in eastern South Africa (https://www.alamy.com/steenbok-raphicerus-campestris-adult-female-standing-on-the-ground-mpumalanga-south-africa-image384329875.html).

This is despite a wide geographical disjunction and the associated reproductive isolation.

It is instead the southernmost subspecies, living in a temperate zone, that is recognisable in photos.

What this means is that only two subspecies can be claimed with confidence, viz.

  • nominate campestris, and
  • neumanni, in a broadened sense.

The remaining subspecies (capricornis and steinhardti) are recognised mainly because of an assumption that their own wide geographical and climatic spread, from the edge of the Namib desert to the edge of miombo woodland in Zimbabwe, must surely be reflected in subspeciation.

It remains possible that even the adaptation to aridity within this species is (https://www.alamy.com/stock-photo-steenbok-raphicerus-campestris-desert-rhino-camp-damaraland-namibia-91113533.html?imageid=222AA12F-6CFE-4847-893B-A221FB5DEA88&p=71799&pn=2&searchId=61806f9903717abe80887586aa50fbc7&searchtype=0) is merely a matter of ecotypes, rather than a matter of subspeciation.

Another important point is that there is enough individual variation in the steenbok to blur any subspecies-distinctions.

The result:

The distinctions among neumanni, capricornis, and steinhardti are so slight that I have found it hard to compile any 'typical' photos of them, in which the subspecific differences are self-evident.

The following is my best attempt, after sifting through thousands of photos.

RAPHICERUS CAMPESTRIS CAMPESTRIS

Western Cape and adjacent parts of Northern Cape and Eastern Cape, South Africa

ground-colour dark

https://www.inaturalist.org/observations/98597843

https://www.inaturalist.org/observations/78046023

https://www.inaturalist.org/observations/52877690

forehead rich-hued

https://stock.adobe.com/ro/images/big-ears/441156073?prev_url=detail

white features (except for buttocks) minimal, particularly on face and inner upper hindleg

https://www.shutterstock.com/image-photo/cape-grysbok-184337792

https://www.istockphoto.com/photo/grysbok-cape-gm1134456769-301460055?phrase=grysbok

RAPHICERUS CAMPESTRIS STEINHARDTI

southern Angola, most of Botswana, Namibia except for eastern Caprivi, part of Northern Cape of South Africa

ground colour pale

https://www.alamy.com/steinbuck-raphicerus-campestris-hoanib-river-namibia-image61349728.html?imageid=205095BC-DD65-4197-BB81-B5D2B32724DD&p=191343&pn=1&searchId=30e86c64bd74ac276119489cea99aea1&searchtype=0

size of ear pinnae maximal

https://stock.adobe.com/ro/video/close-up-from-a-steenbok-resting-at-the-hoanib-riverbed-in-namibia/322384062?prev_url=detail

radial gland noticeable

https://stock.adobe.com/ro/images/cute-steenbok-on-alert-in-front-of-tree-in-etosha-national-park/404356409?prev_url=detail

RAPHICERUS CAMPESTRIS CAPRICORNIS

Mpumalanga, Limpopo, northeastern Kwazulu-Natal, eSwatini, southern Mozambique, Zimbabwe, eastern Caprivi of Namibia, eastern and northeastern Botswana, southwestern Zambia

forehead rich-hued

https://stock.adobe.com/ro/images/male-steenbok-raphicerus-campestris-in-orange-morning-light/313363014?prev_url=detail

https://www.alamy.com/steenbok-raphicerus-campestris-kruger-national-park-south-africa-image237971244.html?imageid=0B54B740-4FC0-4227-931B-0B0098D4D6CD&p=22059&pn=1&searchId=3309ba2d8d68889a061642cd2d5bc830&searchtype=0

size of ear pinnae minimal

https://www.alamy.com/stock-photo-steenbok-raphicerus-campestris-in-a-dry-meadow-south-africa-krueger-76132016.html

radial gland noticeable

https://stock.adobe.com/ro/images/steinbockchen-kruger-national-park-sudafrika/226378977?prev_url=detail

https://stock.adobe.com/ro/images/steenbok-mammal-of-the-kruger-national-park-reserves-and-parks-of-south-africa/273120689?prev_url=detail

RAPHICERUS CAMPESTRIS NEUMANNI

Kenya, Tanzania

Despite the geographical isolation of the East African part of the species-distribution, I have failed to find any consistent difference between this supposed subspecies and capricornis.

https://www.inaturalist.org/observations/135970683

https://www.gettyimages.co.uk/detail/photo/dik-dik-in-the-serengeti-tanzania-east-africa-royalty-free-image/1203979753?adppopup=true

https://www.inaturalist.org/observations/94106167

Anotado por milewski milewski, 03 de octubre de 2022 a las 04:22 PM

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