Question

The only poisonous lizard of the world is
A. Hemidactylus
B. Phrynosoma
C. Heloderma
D. Uromastyx

Answer 1

Hint:-Lizards belong to the order Squamata of class Reptilia. They include scaly skinned reptiles that are found all around the earth except Antarctica and oceanic islands chains. The lizards possess four legs, a round torsos, elevated heads with short necks and a long tail.

Complete step-by-step solution:-
Lizards are animals containing skin that are covered with scales. Scales are overlapping in nature and are made up of keratin. The skin is tough and leathery and is shed occasionally. The presence of scales protects the skin from changing environmental conditions and minimizes the loss of moisture. In some species scales are modified into spines which may be used for display or protection. The lizards reflect various ranges of diets and can be carnivorous, omnivorous, insectivorous etc. In certain groups the lizard tongue is forked and can be extended out of the mouth.
Lizards bear four legs and the legs are the organ of locomotion. Legs bear adhesive pads which help them to climb vertically. Lizards are known to produce toxins and some of them produce powerful venoms. The Gila monster, Heloderma suspectum is a venom producing lizard. The lizard is known to produce a heavy toxin in the modified salivary gland in its lower jaw .The venom is pushed from the gland into the tooth by chewing and by capillary action , the venom comes out of the tooth and is administered into the victim .The symptoms of the bite include heavy pain edema and weakness along with a drop in blood pressure .
Hemidactylus is the common gecko family found in the tropical parts of the world. They are readily adapted and co-exist with humans.
Phrynosoma is known as the horned lizard and possesses a flattened round body and blunt snout. They are found in the arid and semi-arid areas. They are animals with good coloration of the body which serves as a camouflage.
Uromastyx are commonly called spiny tailed lizards and are herbivorous and occasionally feed on insects. Their tail is muscular and heavy and are generally swung at the attacker with heavy velocity.

Therefore, the correct option is option C.

Note:- Lizards are animals consisting of a snake like body with legs, tails and forked tongue. The body is covered with scales which reduces loss of water from it. Some of the lizards produce toxins that are non-fatal in nature. However, the only poisonous lizard is Heloderma suspectum or the Gila Lizard. It produces a highly fatal toxin.