diapsid

American  

[dahy-ap-sid] / daɪˈæp sɪd /

adjective

1. (of reptiles) having two openings in the skull behind each eye, characteristic of the subclasses Lepidosauria and Archosauria, including all living reptiles except turtles.

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noun

1. a diapsid reptile.

diapsid Scientific  

/ dī-ăp′sĭd /

1. Any of various amniotes having a skull with two pairs of temporal openings. Diapsids evolved in the Permian Period and grew longer and better-developed hindlimbs than forelimbs (unlike therapsids). Diapsids evolved into the archosaurs (including the dinosaurs and their descendants the birds) and all modern reptiles except, in some classifications, the turtles.

2. Compare anapsid synapsid therapsid

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Etymology

Origin of diapsid

< New Latin Diapsida (1903); di- ¹, anapsid

Example Sentences

However, molecular studies indicate that turtles descended from a diapsid ancestor.

From Textbooks • Jan. 1, 2015

Early loss and multiple return of the lower temporal arcade in diapsid reptiles.

From Scientific American • Jul. 4, 2012