Term Name: quadrate
Synonyms: quadrates
Definition: The quadrate is the dorsal bone in the jaw joint with the anguloarticular of the lower jaw. Ossification of the quadrate, a cartilage bone, begins as a posteriorly projecting membranous spine between the symplectic cartilage and the preopercle (5.1 mm NL). The body of the quadrate ossifies first at the ball-and-socket articulation with the anguloarticular (6.5 mm). The adult quadrate is shaped roughly like an inverted triangle with a long, posteriorly projecting spine off its posteroventral edge. The presence of a posteroventral or posterior process of the quadrate is a synapomorphy of Teleostei.
Appears at: Larval:Days 7-13 (168.0h-14d, 4.5mm, 8 teeth)
Evident until: Adult (90d-730d, breeding adult)
Ontology: Anatomy Ontology [ZFA:0000621]

Relationships
develops from: palatoquadrate cartilage
is part of: palatoquadrate arch
has parts: quadrate ventral process
is a type of: endochondral bone
overlaps: quadrate-anguloarticular joint quadrate-entopterygoid joint quadrate-metapterygoid joint

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