Tadorna sp.

Mourer-Chauviré, Cécile & Geraads, Denis, 2010, The Upper Pliocene Avifauna of Ahl al Oughlam, Morocco. Systematics and Biogeography, Records of the Australian Museum 62 (1), pp. 157-184 : 167-168

Tadorna sp.

Material. Right humerus, distal part, AaO-2656; left ulna, shaft and distal part, AaO-2657; right radii, proximal part, AaO-749, distal part, AaO-750.

Measurements. See Table 5.

The humerus no. AaO-2656 is larger than those referred to T. tadorna . It was compared with Alopochen , but Alopochen differs in the following characteristics: the distal part of the humerus is more elongated ventrad, the impression of M. brachialis is situated farther from the attachment of the anterior articular ligament, the ventral epicondyle is more projecting both caudally and distally. It was also compared with Sarkidiornis melanotos . In Sarkidiornis , as in Alopochen , the distal part of the humerus is more elongated ventrad than in the Ahl al Oughlam specimen. In Sarkidiornis , the impression of M. brachialis is small and situated more proximally. In particular, it is situated far from the attachment of the anterior articular ligament, whereas in AaO-2656 humerus it is just proximal to the attachment. In Sarkidiornis , the attachment of the anterior articular ligament is tilted and projecting cranially, while in the Ahl al Oughlam fossil it is less projecting and less tilted. The morphological characteristics of the fossil correspond to the genus Tadorna . By its dimensions, it is situated at the upper limit of the Recent T. tadorna and in the variation range of the Recent T. ferruginea , the Ruddy Shelduck. The measurements of the other fragments of ulna and radius are included in the variation range of both T. tadorna and T. ferruginea .

At the present time the Ruddy Shelduck is a breeding resident and non-breeding Palaearctic migrant to North Africa and Western Sahara. It was formerly common and widespread, but it is now extinct as a breeding species in many regions ( Brown et al., 1982).

The Ruddy Shelduck has been recorded as fossil in the lower Pleistocene of Dursunlu, in Turkey, in a layer dating from 0.9 to 1 Ma ( Louchart et al., 1998), and an indetermined Tadornini has been reported in the site of Gomboré II, at Melka Kunturé, Ethiopia, dated at about 0.8 Ma ( Pichon, 1979).