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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.
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
size of ear pinnae maximal
radial gland noticeable
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
size of ear pinnae minimal
radial gland noticeable
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.
Σχόλια
The following is a reminder that the tendency to paleness in R. c. steinhardti is slight:
https://www.alamy.com/stock-photo-tiny-steenbok-antelope-on-the-african-plains-142073043.html?imageid=936CF00D-6F93-463F-9856-AF5DAD8BFD57&p=298851&pn=2&searchId=61806f9903717abe80887586aa50fbc7&searchtype=0
Shift to Post re buttock flag
https://www.alamy.com/stock-photo-steenbok-83374987.html
Exceptionally long horns
https://www.alamy.com/steenbok-raphicerus-campestris-male-stands-in-a-field-south-africa-north-west-province-pilanesberg-national-park-image255403860.html
The following specimens approach the maximum extent of white in Raphicerus campestris:
https://www.alamy.com/stock-photo-steinbok-ram-kruger-national-park-south-africa-12929978.html
https://www.gettyimages.co.uk/detail/photo/david-royalty-free-image/974871476?adppopup=true
Shift
Anterior axillary flag in Raphicerus sharpei:
https://www.istockphoto.com/photo/sharps-grysbok-antelope-in-front-of-a-thorn-bush-gm693678254-128137499?phrase=grysbok
Shows black tongue
https://www.dreamstime.com/stock-photo-funny-face-wild-steenbok-standing-grass-african-savannah-making-image52440922
The following shows that, even in R. c. steinhardti, some individuals have minimal white:
https://www.shutterstock.com/image-photo/side-view-full-body-steenbok-kgalagadi-1712594332
https://www.shutterstock.com/image-photo/side-view-full-body-steenbok-kgalagadi-1712594329
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