[D] Hesperornis rossicus [~/~]
Describer
Nessov & Yarkov, 1993
Time
Cretaceous Late Campanian
Classification
Saurischia Theropoda Tetanurae Coelurosauria Maniraptora Avialae Ornithothoraces Ornithurae [Hesperonithiformes]
Fossilsite
Tzimlyanskoe Reservoir, Don River, Surovikinskii District, Volgograd Province, Belemnellocomax mamillatus zone, Russia; Kristianstad Basin, Ivo-Klack, Scone, Sweden
Info
Orginally namend Hesperornis rossica, however Hesperornis is the masculine gender, thus according to the ICZN, the original epithet rossica is changed to rossicus.
Holotype: VPM 26306/2, proximal portion of the right tarsometatarsus. Referred material, the shaft of a tarsometatarsus, an intermediate phalanx of the fourth pedal digit, a fragment of a thoaric vertebra, and a fragment of a cervical vertebra were all recovered from the same locality in Russia. (Nessov & Yarkov, 1993)
The proximal articular surface of the tarsometatarsus has a very large transverse width and small dorsoplantar depth, the diagonal slant is strongly expressed, the lateral edge of the lateral cotyla exceeds the nintercotylar prominence in proximal direction and the medial cotyla is located more distal in respect to the lateral cotyla. H. rossicus is clearly hesperornithiform, but differs from Hesperornis regalis (Marsh, 1872) from North America in the larger depth of the proximal articular surface, more proximal projection of the lateral cotyla and approximately 20% larger size of the tarsometatarsus.
Nessov & Yarkov, 1993
Time
Cretaceous Late Campanian
Classification
Saurischia Theropoda Tetanurae Coelurosauria Maniraptora Avialae Ornithothoraces Ornithurae [Hesperonithiformes]
Fossilsite
Tzimlyanskoe Reservoir, Don River, Surovikinskii District, Volgograd Province, Belemnellocomax mamillatus zone, Russia; Kristianstad Basin, Ivo-Klack, Scone, Sweden
Info
Orginally namend Hesperornis rossica, however Hesperornis is the masculine gender, thus according to the ICZN, the original epithet rossica is changed to rossicus.
Holotype: VPM 26306/2, proximal portion of the right tarsometatarsus. Referred material, the shaft of a tarsometatarsus, an intermediate phalanx of the fourth pedal digit, a fragment of a thoaric vertebra, and a fragment of a cervical vertebra were all recovered from the same locality in Russia. (Nessov & Yarkov, 1993)
The proximal articular surface of the tarsometatarsus has a very large transverse width and small dorsoplantar depth, the diagonal slant is strongly expressed, the lateral edge of the lateral cotyla exceeds the nintercotylar prominence in proximal direction and the medial cotyla is located more distal in respect to the lateral cotyla. H. rossicus is clearly hesperornithiform, but differs from Hesperornis regalis (Marsh, 1872) from North America in the larger depth of the proximal articular surface, more proximal projection of the lateral cotyla and approximately 20% larger size of the tarsometatarsus.