Secernosaurus koerneri

Overview

Plant-eating dinosaurs with broad, duck-like mouths did not live only in North America. Secernosaurus koerneri was a hadrosaur from Patagonia in South America. It broadens our view of dinosaur distributions at the end of the Cretaceous.^[1][2]

Key facts

The teeth in its jaws formed batteries of many teeth rather than working individually or in pairs. Such structures are compared as plant-processing apparatus. Behind the duck-like mouth lay complex tools for a plant-eating life.^[1]

Time and place

It is known from Late Cretaceous Patagonia. Major specimens have been studied as coming from layers close to about 70 million years ago. Localities around the Chico River and Lake Colhué Huapi in present-day Chubut Province, Argentina, are important for comparisons.^[1]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

Type specimen FMNH PP13423 includes fragments of dental batteries, the base of the skull, neck and back vertebrae, ribs, and parts of the shoulder and forelimbs. Several body regions can be compared with other hadrosaurs. Each fragment helps fill out the outline of this broad-mouthed dinosaur.^[1]

The Natural History Museum in London gives a body length of about 3 m for the genus Secernosaurus.^[3]

Habitat and reproduction

Hadrosaurs were a group of plant-eating dinosaurs. The many teeth forming their dental batteries processed vegetation. Comparing Patagonian specimens with relatives from other continents reveals how far dinosaurs with similar feeding apparatus spread.^[1][2]

Fossil discovery

After Brett-Surman introduced it as a new species in 1979, research on South American hadrosaurs continued. In 2010, the relationship between this species and material of Kritosaurus australis was reexamined. New specimens and anatomical comparisons continue to refine the names and relationships of dinosaurs in this region.^[1][2]

References

1. Prieto-Márquez & Salinas2010 — Secernosaurus and South American hadrosaurs
2. Aragosaurus — Bonapartesaurus and Patagonian hadrosaurs
3. Natural History Museum, London — Secernosaurus
4. American Museum of Natural History — The crest of Corythosaurus
5. Brown (1914) — Description of Corythosaurus casuarius

Research questions

How were South American duck-billed dinosaurs related to species on other continents? Analyzing features of the head and body together allows study of movement between continents and diversification within regions. This dinosaur encourages us to consider geography and evolution together.^[1]

Observation

Move your gaze from the broad mouth to the jaws and trunk.^[1]