Troodontidae

 Troodontidae is a family of bird-like theropod dinosaur that appeared in the late Jurassic and got extinct as a family in

Several members of the troodontidae family

the Late Creataceous. Fossils of members of the Troodontidae family have been found in North America, Europe and Asia, mostly Mongolia and China. The type species of the Troodontidae family is the Troodon formosus, also the biggest and best-known troodontid.

Characteristics

Size

Troodontids were small theropods, the biggest of them reaching only 200 lbs in wheight. The largest known

Troodon formosus size comparison

troodontid is the Troodon, being 8 feet ( or 2meters) long, and the smallest is Anchiornis, being 1 foot (or 30 centimeters) long.

General characteristics

Troodontids have unusually long legs, with a large sickle-claw on the second toe of each foot. However, this claw was not so big as in their cousins, the Dromaeosaurids . Furthermore, they have a short and deep trunk, long S-shaped necks, long forelimbs, with large, three-digitated hands that could fold against the body, and a long, stiff tail, that was used as control-balancing and rudder when running.

Intelligence and senses

Troodontids have also unusually large brains and eyes, suggesting that they were extremely smart dinosaurs for their size. As their eyes were bigger and front-pointed, their binocular vision was maybe even better than those of the Dromaeosaurids .

Their ears are asymettrical, as one year is placed higher in the skull than the other, fact that resebles modern owls. This thing suggests that troodontids had an acute sense of hearing, and that they used this sense while hunting, for localizing the prey.

Behavior 

Most of the troodontids members are considered to be active predators, but some evidences such as many small, serrated teeth, large dentical size and a U-shaped jaw may suggest that at least some of the Troodontids (like Troodon) were omnivorous.

Classification

• Anchiornis huxleyi;
• Arcaeornithoides deinosauriscus;
• Borogovia gracilicrus;
• Byronosaurus jaffei;
• Bradycneme draculae ;
• Eosinopteryx brevipenna;
• Geminiraptor suarezarum;
• Koparion douglassi;
• Linhevenator tani;
• Mei long;
• Pectinodon bakkeri;
• Philovenator curriei;
• Saurornithoides mongoliensis;
• Sinornithoides youngi;
• Sinusonanus magnodens;
• Sinovenator changii;
• Talos sampsoni;
• Tochisaurus nemegtensis;
• Urbacodon itemirensis;
• Xiaotingia zhengi;
• Xixiaosaurus henanensis;
• Zanabazar junior;
  • ​Jifengopteriginae:
    • ​Jifengopteryx elegans;
  • ​Elopteryginae:
    • ​Elopteryx nopcsai;
  • ​Troodontinae:
    • ​Troodon formosus;

Dubious, possible troodontids

• Paronychodon lacustris;
• Euronychodon portucalensis;
• Richardoextensia gilmorei;