Greenland

A hard-won vertebrate fauna, including mammals, has been collected by Farish A. Jenkins, Jr., and associates from Upper Triassic rocks of Jameson Land, northeastern Greenland, at more than 71° N latitude (figure 2.8). Thus far, the assemblage includes dinosaurs and other archo-saurs, turtles, labyrinthodonts, and fishes, in addition to four mammals. The fauna is very similar to that of the Norian part of the Keuper in Western Europe, sharing such taxa as Gerrothorax, Cyclotosaurus, Proganochelys, Aetosaurus, and Plateosaurus; current evidence suggests that it is at least as old as mid-Norian (Jenkins et al., 1994). The mammals are thus some of the very earliest known.

The occurrences are in the Malmros Klint and 0rsted Dal members of the Fleming Fjord Formation. This unit includes playa-mudflat systems, loess beds, sand flats, flat pebble conglomerates, and paleosols. Climate is inferred to have varied from humid to dry (with seasonal rainfall) to arid and to have been controlled by Milankovich cycles (Jenkins et al., 1994).

Haramiyavia clemmenseni (originally placed in the Haramiyidae but now referred to its own, monotypic family) is based on a partial skeleton with associated jaws and cranial elements (Jenkins et al., 1997; see also Butler, 2000). Given the fact that haramiyids and dentally similar mammals (Allotheria) of the Late Triassic-Early Jurassic are known only by isolated teeth, the find is of great significance—whatever the affinities of Haramiyavia might prove to be (chapter 8). The specimen unambiguously shows the orientation and position of the cheek teeth and is sufficiently complete to suggest that jaw movement was mainly orthal, rather than palinal, as it is in multitubercu-lates (Jenkins et al., 1997, but see Butler, 2000).

The other mammals (table 2.1) known from the Fleming Fjord Formation are represented only by isolated teeth (Jenkins et al., 1994). Two incomplete molariforms testify to the presence of a rather large, unidentified "tricon-odont." Brachyzostrodon, a morganucodontan otherwise known from the Late Triassic of Saint-Nicolas-de-Port, France (Sigogneau-Russell, 1983b; Hahn et al., 1991), may be present in the fauna, though the fragmentary nature of the specimen (half of a molar) leaves positive identification in question. Kuehneotherium, a rare but widespread "symmetrodontan" otherwise known from both Triassic and Jurassic deposits of Western Europe (see earlier), is probably represented in the Fleming Fjord Formation as well.

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