page_title: Glossary of dinosaur anatomy
section_title: G
hierarchical_section_title: Glossary of dinosaur anatomy / G
caption_attribution_description: English: Fossil of Poekilopleuron, an extinct dinosaur. Took the photo at Muséum national d'histoire naturelle, Paris. Español: Fósil de Poekilopleuron, un dinosaurio extinto. Fotografía tomada en el Museo Nacional de Historia Natural de Francia, en París. Français&#160;: Fossile de Poekilopleuron, un dinosaure disparu. Photographie prise au Muséum national d'histoire naturelle, à Paris.
context_page_description: This glossary explains technical terms commonly employed in the description of dinosaur body fossils. Besides dinosaur-specific terms, it covers terms with wider usage, when these are of central importance in the study of dinosaurs or when their discussion in the context of dinosaurs is beneficial. The glossary does not cover ichnological and bone histological terms, nor does it cover measurements.
context_section_description: gastralia 
  
  Gastralia (singular: gastralium) are dermal bones present within the dermis of the abdomen between the sternum and pubis. Gastralia are primitively present in dinosaurs and can be found in basal sauropodomorphs and theropods, but have been independently lost in sauropods, ornithischians, and neornithines (today's birds). When present, they are arranged in 8 to 21 rows, each of which consisting of four elements: A right and left medial gastralium articulate at the body midline in a zig-zag like fashion, while a lateral gastralium articulates with the lateral end of each medial gastralium. The first and last row may be fused into a single, bow-like structure termed a chevron-shaped gastralium. The use of the term "abdominal rib", which has been sometimes used for gastralia and other abdominal structures, is ambiguous thus discouraged.
  glenoid
  
  The glenoid is the articulation surface formed by the coracoid and scapula that receives the head of the humerus, forming the shoulder joint. A concave and circular structure, it is edged by a bony rim, and located on the posterior surface of the coracoid and the posterodistal surface of the scapula.
caption: Gastralia of Poekilopleuron
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