Question

Which of the following is not a reptile?
A. Sphenodon
B. Hemidactylus
C. Ichthyophis
D. Ichthyosaurus

Answer 1

Hint:- Reptiles are the cold-blooded tetrapods and produce amniotic eggs. Tuatara, lizards, crocodiles, and snakes are some examples of reptiles. The body of reptiles is covered with scales or bony plates that protect them. Some of the early amphibians also have scales of bony plates on their body surface.

Complete step-by-step solution:-
Sphenodon is commonly called tuatara and looks like lizards. Their species are categorized as endangered due to the reduced population size. They are the amniotes and have vertebrae that are concave at both ends. They belong to the family Sphenodontidae of the class Reptilia.
Hemidactylus is commonly called wall lizard or geckos. It is a nocturnal reptile and belongs to the subfamily Gekkoninae of the class Reptilia. Adhesive vacuum pads present at their limbs allow them to run on walls.
Ichthyosaurus were common reptiles in the Jurassic period. They were marine reptiles, predaceous, and had a streamlined body with four limbs.
Ichthyophis is commonly called caecilian and is mainly found in the tropical regions. It belongs to the order Apoda of the living amphibians. They lack limbs and girdles and have short tails if present. Their body is covered with bony plates. The species Ichthyophis beddomei is endemic to the Indian Western Ghats.
So, the correct answer is option C. Ichthyophis.

Note:- Amphibians are the four-limbed vertebrates and were the first organism to inhabit the land habitats. All the living amphibians are classified into three orders. Apoda includes limbless amphibians. The orders Anura and Caudata include tailless and tailed amphibians respectively.