I. Family Boidea

This family consists of primitive snakes, which have many features that relate them to their lizard like ancestors. All the snakes of this family are non-poisonous and mainly feed on small birds and rodents. They capture their prey with their strong and pointed teeth and kill them by the constriction process. Some of the larger Pythons normally feed on large mammals like cows and deer. Most of them are terrestrial but few aquatic species are also found in this family. They are widely distributed in a variety of habitats.

The body is cylindrical and covered with smooth or keeled scales. The tail is usually short and prehensile. The vestiges of the hind limbs and pelvis are present.  Their eyes are round in shape and possess acute vision. The pupil is vertical and nostrils are present on both sides of the head and are separated by small scales. They are either oviparous or viviparous and parental care can be seen in some primitive species. These snakes are nocturnal in habit but can be seen during daytime in winters. 

Beside Pakistan, these snakes are also found in Africa, South East Asia, North and South America and Australia. In Pakistan, 3 genus and 4 species of this family are found, which are as follows: