1. Coelurosauria is a Greek word which means (Coel-hollow, uro –tail, Sauria- Lizards) ie, Coelurus lizards or hollow tailed lizards. They have the largest Coelurosaurs including Tyrannosaurus and smallest one mainly Microraptor, Parvicursor etc. Coeurosaurs includes tyrannosaurs, ornithomimosaurs, and maniraptors.
i. Tyrannosaurs were having fused nasals. U-shaped pr-maxillary teeth, and slender metacarpals.
ii. Ornithomimosaurs were having a long neck, small skull, all same length matacarpals.
iii. Maniraptors have Large fore-limbs, large bony sternum, pubic pointing backward.
Coelurosaurs are the smallest types and feed on smaller prey.
2. Characteristics of Coelurosauria:
a. They were bipedal i.e. two feet (bi-two, Pedal-feet)
b. They were carnivorous.
c. Lower arm bone (ulna) was bowed.
d. Their lower leg bone(tibia) was longer than the upper leg bone (femur)
e. Their tail was stiffened towards the tip
Some other peculiar features of Coelurosaurs are:
(a). Enlarged brains: It is one of the main features of Coelurosaurs. They have a large brain that was at least double the size of those of other theropods having the same body size.
(b). They have long narrow, slender hand i.e. They have tridactyl (Tri-three, Dactyl-Digits) on the extremity of the manus (distal forelimb)
(c). They have Kayak-shaped (v-shaped) chevrons making the distal part of the tail particularly slender
(d). They have long narrow feet or metatarsals
3. As I already explained in reply to query no. 2, the Coelurosaurs possess slender grasping hands with tri-dactyl manus that means they have three fingers.
4. Yes, some Coelurosaurs are still live. Out of the three types of Coeurosaurs, Maniraptora, the smallest coelurosaurs, includes birds, the only progenies of coelurosaurs that are still alive. They first appear in the Middle Jurassic period and persist ever since. They have a resemblance to Dinosaurs. They belong to class Reptilia and suborder Dinosauria. Actually, Dinosaurs were the connecting link between reptiles and birds and was having a lizard-like tail but features like birds. Coelurosaurs are also feathered dinosaurs.
5. They have a global presence and present in almost all continents.