Is Gazella marica just an Arabian form of Gazella subgutturosa?

Based on geographical distribution, the sand gazelle (Gazella marica, see https://www.inaturalist.org/observations/55395922 and https://www.flickr.com/photos/120036191@N02/15075998166) seems to be a somewhat pallid Arabian form of the widespread goitered gazelle (Gazella subgutturosa, see https://alchetron.com/Goitered-gazelle#goitered-gazelle-f4036415-25e8-405c-9b90-ac086cae726-resize-750.jpeg and https://www.flickr.com/photos/korkeasaarizoo/48527469291/). However, the relationship between the two forms (which were previously regarded as subspecies) is complicated.

A problem with explaining the pallor of the sand gazelle as arid-adapted is that subspecies yarkandensis of the goitered gazelle (see https://mongolia.gogo.mn/r/156358 and https://rove.me/to/mongolia/wildlife-watching?photo=7) occurs in the extreme aridity of the Gobi Desert without particular pallor.

The sand gazelle is surprisingly smaller than the goitered gazelle. This diminutive status is in line with all the other large mammals of the Arabian Peninsula, but is hard to explain ecologically.

The larynx may differ in the two forms. The goitered gazelle has what is perhaps the oddest laryngeal anatomy of any ungulate (https://onlinelibrary.wiley.com/doi/10.1111/j.1469-7580.2011.01361.x). Nobody seems to have studied the larynx of the sand gazelle, and I have seen only one photo of this well-photographed species showing a (rutting?) male with a particularly noticeable larynx (see https://eol.org/pages/129520/media?license_group=cc_by_sa).

The female horns are surprisingly different even considering the whole genus Gazella: extremely well-developed in the sand gazelle (see https://www.inaturalist.org/observations/30681543 and https://www.inaturalist.org/observations/84177386) but extremely poorly developed in the goitered gazelle (see https://en.wikipedia.org/wiki/Goitered_gazelle#/media/File:Female_goitered_gazelle,_Shirvan_National_Park,_Azerbaijan.jpg and https://animaldiversity.org/accounts/Gazella_subgutturosa/pictures/collections/contributors/david_blank/goiteredgazelles8/).

The pattern on the flank may differ slightly. In the sand gazelle, the banding conforms with that in gazelles generally, in that the darker ventral flank-band runs obliquely towards the shoulder, leaving enough space for the paler flank-band above it to be triangular. In the goitered gazelle both bands tend to run horizontally, the darker ventral band running towards the scapula and the paler band tending linear rather than triangular.

Perhaps the clearest clue to the close relationship between the two is that both display their dark tails differently from other members of their genus. Whereas most species of Gazella display the tail mainly by wagging it briskly while walking, the sand gazelle and goitered gazelle display the tail mainly by holding it up while running (see, respectively, https://www.flickr.com/photos/lesnafi/11877272684 and https://www.flickr.com/photos/tom_martin/30486954365/).

פורסם על-ידי milewski milewski, ספטמבר 14, 2020 11:59 אחה"צ

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