A previously overlooked difference between tsessebe and topi: the dark haunch-patch relative to the ischiopygal flag

@simontonge

In recent Posts, I have

• acknowledged the similarity between the tsessebe (Damaliscus lunatus) and the topi (Damaliscus jimela), such that it is ambivalent whether they are different species, or mere subspecies of a single widespread species,
• pointed out the pale, sheeny buttocks (ischial surface) of both the tsessebe (https://www.gettyimages.ie/detail/photo/tsessebe-royalty-free-image/520403558?phrase=damaliscus%20korrigum&adppopup=true) and the topi (https://www.inaturalist.org/observations/101304258),
• recognised and named the pattern on the buttocks, adjacent haunches, and rump as an ischiopygal flag, and
• described in detail the 'dark' haunch-patch of the topi.

The main differences between the tsessebe and the topi are as follows:

• The horns have obviously different orientations.
• The colouration of the tsessebe is less vivid than that of the topi.
• The tsessebe tends to look darker, overall, than the topi.
• The tsessebe lacks the subsidiary dark markings on the face, viz. on the cheeks and upper lips, found on some/most individuals of the topi.

The aim of this Post is to show an additional difference, viz. the extent of the 'dark' haunch-patch on its posterior side.

In the tsessebe, the 'dark' haunch-patch does not extend on to the posterior part of the haunch, which is similar to the buttocks in its (pale) colouration. In the topi, by contrast, the 'dark' haunch-patch extends to the posterior border of the haunch in all individuals, and encroaches towards the base of the tail in a few individuals.

The maximum extent of the 'dark' haunch-patch is shown in

• tsessebe: https://www.alamy.com/stock-photo-tsessebe-damaliscus-lunatus-ithala-game-reserve-south-africa-38233447.html?imageid=BC0E7016-21E3-4A40-BDD7-E505E28177DC&p=22059&pn=1&searchId=303cfda7336cba6c5732f1db91b12f81&searchtype=0
• topi: https://www.inaturalist.org/observations/144358826 and https://www.inaturalist.org/observations/121431587 and https://www.gettyimages.ie/detail/photo/topi-antelope-royalty-free-image/1131854521?phrase=damaliscus%20korrigum&adppopup=true.

One of the reasons why this difference has previously been overlooked is that the 'dark' haunch-patch, in both the tsessebe and the topi, tends to be obscured by sheen and gloss.

In both the tsessebe and the topi, the conspicuousness of the ischiopygal flag is mainly a result of paleness, centred around the anus.

A difference is that, to the limited degree that dark/pale contrast is involved, the dark is provided by

• the general darkness of the figure, in the case of the tsessebe (http://elelur.com/data_images/mammals/tsessebe/tsessebe-05.jpg), vs
• the particular darkness (in some illuminations) of the haunch-patch, in the case of the topi (https://fineartamerica.com/featured/1-side-profile-of-a-topi-standing-panoramic-images.html?product=art-print).

TSESSEBE

https://stock.adobe.com/search?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=1&filters%5Bcontent_type%3Atemplate%5D=1&filters%5Bcontent_type%3A3d%5D=1&filters%5Bcontent_type%3Aaudio%5D=0&filters%5Binclude_stock_enterprise%5D=0&filters%5Bis_editorial%5D=0&filters%5Bfree_collection%5D=0&filters%5Bcontent_type%3Aimage%5D=1&k=damaliscus&order=relevance&safe_search=1&search_page=2&get_facets=0&search_type=pagination&asset_id=496136014

https://www.discountafricanhunts.com/uploads/dah164149485953038.jpg

https://walleigh.com/africa/botswana/botwana-animals-rarely-or-never-seen-on-previous-safaris#!prettyPhoto[1]/ML/1917

https://dewetswild.com/2016/08/19/tsessebe/#jp-carousel-11105

https://dewetswild.com/2016/08/19/tsessebe/#jp-carousel-21675

https://dewetswild.com/2016/08/19/tsessebe/#jp-carousel-6459

https://www.alamy.com/tsessebe-damaliscus-lunatus-antelope-standing-looking-into-the-distance-with-grass-in-its-mouth-in-the-wild-at-mokala-national-park-south-africa-image236000342.html?imageid=BDA0E736-B002-43C7-ADCA-7C6D4BB3D264&p=698884&pn=1&searchId=303cfda7336cba6c5732f1db91b12f81&searchtype=0

https://www.alamy.com/stock-photo-rare-tsessebe-antelope-damaliscus-lunatus-south-africa-31757362.html?imageid=E55A3C6B-E961-432E-BC94-FAA44445B703&p=70019&pn=1&searchId=303cfda7336cba6c5732f1db91b12f81&searchtype=0

https://www.alamy.com/tsessebe-damaliscus-lunatus-antelope-grazing-on-the-savannah-grass-in-the-wild-at-mokala-national-park-in-south-africa-with-its-back-to-the-camera-image236000180.html?imageid=29D85F27-E15E-4293-8F9D-35217F745F94&p=698884&pn=1&searchId=303cfda7336cba6c5732f1db91b12f81&searchtype=0

https://www.alamy.com/stock-photo-tsessebe-with-young-damaliscus-lunatus-okavango-delta-botswana-25902406.html?imageid=3EE4F44A-E996-4E63-8EC7-8FC7F4CA314A&p=74587&pn=2&searchId=5a975ca1461ca04a69177e15a216926e&searchtype=0

https://www.alamy.com/stock-photo-tsessebe-antelope-21869805.html?imageid=A09602DE-0FD6-4592-A288-E6888B72C836&p=4877&pn=2&searchId=5a975ca1461ca04a69177e15a216926e&searchtype=0

TOPI

https://www.alamy.com/stock-photo-topi-damaliscus-korrigum-adult-on-termite-hill-kenya-111494921.html?imageid=0DDE2EE5-6061-4F67-9860-79B358AEC9C7&p=329545&pn=6&searchId=299ba9a318ad97c1aa8f067cb48a3cbf&searchtype=0

https://www.alamy.com/stock-photo-topi-and-zebra-masai-mara-north-reserve-kenya-21744319.html?imageid=7B125122-AED9-4AA6-9F20-A60C5DA0404C&p=11788&pn=2&searchId=b7479a4a7e8485f2798a8b630caab8b2&searchtype=0

https://www.dreamstime.com/topi-grassland-looking-back-camera-image135604783

https://www.alamy.com/africa-kenya-northern-serengeti-plains-maasai-mara-topi-wild-damaliscus-lunatus-jimela-subspecies-of-the-common-tsessebe-image395593006.html?imageid=BFB2C784-B476-4E17-9332-A3F186197FAF&p=88978&pn=2&searchId=5a975ca1461ca04a69177e15a216926e&searchtype=0

https://www.shutterstock.com/it/image-photo/hartebeest-topi-seen-behind-729881761

https://www.istockphoto.com/photo/topi-dunging-why-you-are-looking-my-mom-gm503311653-44553816

https://www.alamy.com/stock-photo-kenya-a-topi-stands-on-a-termite-mound-in-masai-mara-national-reserve-26888009.html?imageid=AD08B54A-5038-4040-A4EB-D06C68A91D0C&p=37852&pn=1&searchId=2b231e9c97eacc75f20f7a32704237f7&searchtype=0

https://www.alamy.com/topi-damaliscus-lunatus-topi-masai-mara-national-reserve-kenya-east-image62900688.html?imageid=6A6C95C5-86A3-4BDB-B540-CCF191B4F71A&p=195690&pn=1&searchId=2b231e9c97eacc75f20f7a32704237f7&searchtype=0

https://www.alamy.com/stock-photo-a-topi-antelope-damaliscus-korrigum-and-plains-zebras-masai-mara-national-78058917.html?imageid=EFA231C2-422B-4C63-9926-B1F4AF74EE4C&p=70019&pn=1&searchId=2b231e9c97eacc75f20f7a32704237f7&searchtype=0

https://www.alamy.com/stock-photo-male-topi-masai-mara-game-reserve-kenya-36095631.html?imageid=7897C1FB-B2DF-4C3B-8061-9C7E18F56E3D&p=11788&pn=2&searchId=b7479a4a7e8485f2798a8b630caab8b2&searchtype=0

https://www.alamy.com/stock-photo-topi-and-calf-masai-mara-north-reserve-kenya-21744531.html?imageid=59618AE0-9399-411E-A223-B8DEFBEA3D99&p=11788&pn=2&searchId=b7479a4a7e8485f2798a8b630caab8b2&searchtype=0

https://www.alamy.com/stock-photo-topi-with-young-damaliscus-lunatus-jimela-maasai-mara-national-reserve-53543734.html?imageid=DB380191-968B-4E54-917E-5A268D03C1D6&p=22059&pn=2&searchId=b7479a4a7e8485f2798a8b630caab8b2&searchtype=0

https://www.alamy.com/stock-photo-topi-damaliscus-lunatus-topi-new-born-calf-standing-near-its-mother-47468821.html?imageid=9E3F8DDA-62BD-403A-A0CB-CA0B09376EF6&p=86574&pn=4&searchId=75c0958af17d2dc41e195ecb616894c3&searchtype=0

https://www.alamy.com/stock-photo-topi-antelope-in-the-savannah-of-kenya-74856397.html?imageid=5CE60153-00C0-4431-9FE4-18A9F4D459DE&p=196415&pn=4&searchId=75c0958af17d2dc41e195ecb616894c3&searchtype=0

https://www.alamy.com/topi-damaliscus-lunatus-mother-cleaning-a-newborn-foal-maasai-mara-kenya-image338867103.html?imageid=4AE9C5FB-821A-42C5-A7F2-ED3C68F6EA33&p=202574&pn=4&searchId=75c0958af17d2dc41e195ecb616894c3&searchtype=0

https://www.alamy.com/stock-photo-hunters-topi-damaliscus-lunatus-topi-in-savanna-kenya-masai-mara-national-47887774.html?imageid=CC76163C-B5C6-484E-81FA-D96756D6A7FF&p=33612&pn=4&searchId=75c0958af17d2dc41e195ecb616894c3&searchtype=0

For an index to my many Posts about the genus Damaliscus, please see https://www.inaturalist.org/journal/milewski/78238-an-index-to-my-posts-on-genus-damaliscus#.

Posted on Απρίλιος 20, 2023 0442 ΜΜ by milewski