Canadaga Hou, 1999

Canadaga Hou, 1999 (Vertebr. Palasiat. 37 (3), July: 228. NcZ) "Canadian bird"*
KAN-uh-DAY-guh (Canada + ?Lat. - ago "having characteristics of" + -a) (f) named to indicate a fossil bird from northern Canada. Canadaga is a very large hesperornithid known from three neck vertebrae (Holotype: NMC 41050 (Canadian National Museum)), as well as referred material apparently belonging to juveniles (a caudal vertebra and parts of two femurs). The fossil material comes from Bylot Island, Northwest Territories, Arctic Canada, and dates from the Late Cretaceous (middle Maastichtian), thus representing the latest occurrence of a hesperornithid so far discovered. The preserved neck vertebrae likely are vertebrae 15-17; vertebra 16 has a centrum 28 mm long. The vertebrae show many similarities to those of Hesperornis but differ in a number of details, including having a fan-shaped expansion on the end of the centrum while the middle part of the centrum is constricted, and having a large and deep concavitas lateralis occupying almost the entire lateral surface of the centrum. The transverse process on the vertebrae has a deep cavity probably connected with the neural canal, a character which distinguishes Canadaga from other known hesperornithids. An adult Canadaga may have been more than 1.5 m (5 ft) long. The discovery of juvenile bones suggests suggests Canadaga may have bred in colonies in the high arctic, as suggested for some species of the earlier Hesperornis.
Type Species: Canadaga arctica [ARK-ti-kuh] Hou, 1999: "arctic," referring to its discovery in the Arctic region of northern Canada, one of the most northerly occurrences of hesperornithids known. Ornithurae Hesperornithiformes Hesperornithidae Late Cretaceous (mid-Maastrichtian) NA. [added 7/2000]

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