Open Paleo

Leptorhynchos

Longrich et al., 2013 LEP-toh-RIN-koss /ˌlɛptəuˈrɪŋkəus/

From Greek 'leptos' meaning 'slender' or 'thin' and 'rhynchos' meaning 'beak' or 'snout', referring to a slender beak.

83.6–72.2 million years ago Campanian, Late Cretaceous
Late Cretaceous stages

Leptorhynchos is an extinct genus of caenagnathid theropod from the Late Cretaceous of what is now the US state of Texas, although it has been suggested to also exist in Alberta and South Dakota. The type species is L. gaddisi, and it is currently the only widely accepted valid species. The generic name of Leptorhynchos comes from the Greek "leptos" meaning "small" and "rhynchos" meaning "beak". The specific epithet is in honor of the Gaddis family, who owned the land on which the holotype was discovered.

Diagnosis

  1. More anteriorly projecting tip of the beak than L. elegans
  2. Strongly rounded anteroventral margin of the symphysis
  3. Lateral occlusal margins of the dentaries not as strongly divergent in dorsal view
  4. Tip of the beak narrower and more spoon-shaped in dorsal view

Species

Leptorhynchos gaddisi Longrich et al., 2013

Type species

Named in honor of the Gaddis family, who owned the land on which the holotype was discovered.

Holotype
TMM 45920-1 , Texas Memorial Museum, Austin, Texas, USA (used for collections now housed in the Vertebrate Paleontology Collections at the Jackson School Museum of Earth History, Austin, Texas, USA), now called the Texas Science and Natural History Museum
Material
Single fused mandible
Horizon
lower Alto Shale Member, Aguja Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
Terlingua area, Texas, United States

References

  1. Longrich, N. R.; Barnes, K.; Clark, S.; Millar, L. (2013). Caenagnathidae from the Upper Campanian Aguja Formation of West Texas, and a Revision of the Caenagnathinae. Bulletin of the Peabody Museum of Natural History 54(1): 23-49. Bulletin of the Peabody Museum of Natural History. doi:10.3374/014.054.0102 longrich2013a
  2. Lehman, T. M.; Wick, S. L.; Macon, C. C.; Wagner, J. R.; Waggoner, K. J.; Brink, A. A.; Shiller, T. A., II (2024). Stratigraphy and depositional history of the Aguja Formation (Upper Cretaceous, Campanian) of West Texas, southwestern USA. Geosphere 20(3): 825-879. Geological Society of America. doi:10.1130/GES02662.1

    Formally erects the Alto Shale Member for the interval previously called the upper shale, and places this species in its lower part.

    lehman2024a