Anatalavis Olson & Parris, 1987

Anatalavis Olson & Parris, 1987 (Smithson Contrib Paleobiol No. 63: 11. NcZ) (Charadriiformes NcZ) "duck-winged bird"*
an-a-TAY-la-vis (Lat. anat- (anas) "duck" + Lat. ala "wing" + Lat. avis "bird") (f) named for the shape of the humerus, resembling somewhat that found in modern ducks; for "Telmatornis" rex Shufeldt, 1915. Anatalavis was originally based on two humeri (Holotype: YPM 902 (Yale Peabody Museum)) found in the Hornerstown Formation in New Jersey (dated either to the latest Cretaceous or earliest Paleocene), distinguished from Telmatornis Marsh, 1870 by their much shorter, more robust and curved shafts. The recent discovery of very similar humeri associated with a partial skeleton (missing hindlimbs) and skull from the Eocene of England provides much more information on the genus (Olson 1999, Smithsonian Contributions to Paleobiology 89:231-243). The second species (Anatalavis oxfordi) is much larger and shares a number of characteristics with the modern Australian Magpie goose (Anseranas), most notably a V-shaped furcula with a large, deep symphysis. Anatalavis has a very broad, rounded, thin duck-like bill, indicating it was filter feeder with jaw muscles specialized for straining food (unlike the modern Magie goose, which has a strong, deep, hooked bill for digging outplant material); the short, robust humerus (with proportions more that of a falcon) suggests it was a strong, rapid flyer; the shape of the pelvis resembles that of wading birds rather than that of swimming duck-like birds. How much the Late Cretaceous type species would have resembled the early Eocene species is not clear without more skeletal material, but the new find suggests that specialized types of modern birds had already evolved by the end of the Mesozoic. The exact date of the basal Hornerstown Formation is still debated, and it may represent early Paleocene rather than Late Cretaceous.
Type Species: Anatalavis rex (Schufeldt, 1915): "king," to represent a species of Telmatornis larger than Marsh's Telmatornis priscus --Olson and Parris (1987) erected the new genus Anatalavis for Schfeldt's species. Their original classification placed it in the order Charadriiformes, family Graculavidae. However, the new Eocene material indicates it is the earliest representative of the waterfowl order Anseriformes, closely related to the modern Magpie goose in the family Anseranatidae. Additional Species: Anatalavis oxfordi [OKS-for-die] Olson, 1999: for Andrew Oxford, the English fossil collector who found the specimen in the early Eocene (Ypresian) London Clay at Walton-on-the-Naze, Essex, England. Ornithurae Anseriformes Anseranatidae Anatalavinae Late Cretaceous (or Paleocene) NA, Eocene Eur. [revised 8/2000]

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