Cf Anser Sp Or Chen Sp

REFERRED MATERIAL Partial premaxilla, DMNH 12807 (fig. 12.1A).

provenance Location 644, Velvet Room, grid 16, level 19 (I).

DESCRIPTION The relatively more posterior position of the nares on the premaxilla is one character that distinguishes Anser and Chen from Branta, which has nares placed farther anteriorly and nearer to the tip of the bill. The fossil is relatively larger than A. albifrons, C. caerulescens, and C. rossi and is too fragmentary for more specific identification. It may represent an undescribed species, but additional material is needed.

ANAS CRECCA LINNAEUS, 1758, OR A. DISCORS LINNAEUS, 1766

REFERRED MATERIAL Left tarsometatarsus, DMNH 30205.

provenance Location 1349, Mark's Sink (PC-10).

DESCRIPTION This specimen compares well in size to either of these two species, but no osteological characters of this element reliably distinguish either taxon.

ANAS SP.

REFERRED MATERIAL Humeral right and left coracoids, DMNH 30198; right coracoid missing sternal end, DMNH 12037; proximal right and left scapulae, DMNH 30198; right carpometacarpus, DMNH 30196.

PROVENANCE 30196: Location 1342, Ferret Room (PC-3); 30198: Location 644, Velvet Room, grid 21, level 2 (B); 12037: Location 644, Velvet Room, grid 7, below level 23 (no age correlation).

DESCRIPTION All specimens except DMNH 12037 are similar in size to Anas clypeata. DMNH 12037 is from a small duck and probably represents a species of teal.

AYTHYA cf. A. AMERICANA (EYTON, 1838)

REFERRED MATERIAL Humeral right coracoid, DMNH 30191.

provenance Location 644, Velvet Room, grid 26, level 1 (A).

ANATIDAE, INDETERMINATE

REFERRED MATERIAL Partial furculum, DMNH 12351; two right coracoids with ends damaged, DMNH 30205; partial right coracoid, DMNH 10895; sternal half of right cora-coid, DMNH 43331; left coracoid missing ends, DMNH 30161; distal right humerus, DMNH 30078; distal right carpometa-carpus, CM 75128.

provenance 10895: Location 644, Velvet Room, grid 7, level 23 (no age correlation); 12351: Location 644, Velvet Room, grid 17, level 3 (B); 30161: Location 644, Velvet Room, mixed; 30078, 30205: Location 1349, Mark's Sink (PC-10); DMNH 43331: Location 1349, Mark's Sink, level 11; CM 75128: Badger Room.

DESCRIPTION These specimens are too fragmentary for specific identification. The furculum (DMNH 12351) is most similar to Oxyura jamaicensis, while the other specimens represent either Anas, Aythya, or Bucephala.

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