Syrinx is the voice box present in the region of bifurcation of trachea.

Phleobotmus or sand fly spreads kala azar.

Hemichordata is a phylum of Chordata-like animals, which have pharyngeal gill slits. The body is worm-like and divisible into proboscis, collar and trunk.

Asteroidea is a class of subphylum Elutherozoa of phylum Echinodermata. It has flat and star-shaped animals and small pedicellariae.

A movable stalk supports the eyes present in molluscs. So, it is called as an eye stack of molluscs.

Herdmania is a tunicate. It belongs to the subphylum Urochordata and has a free swimming tadpole larva that shows retrogressive metamorphosis.

Class Bivalvia or Pelecypoda consists of filter feeder molluscs in which the shell is external and made up of two valves jointed dorsally by a hinge joint. Pinctada or pearl oyster is present in pelecypoda.

In Peripatus, there is the presence of primitive characters such as presence of cilia, nephridia, unjointed legs and there is the absence of external segmentation. Due to the presence of these characters, Peripatus is considered to be the most primitive arthropod.

The head and foot come together and fuse to form a cephalopod. Cephalopods have eyes similar to those of a vertebrate.

Platypus is a Prototherian and is a small nocturnal and oviparous animal. It is found in Australia and Tasmania.

Viper possesses haemotoxic poison which causes haemolysis (destruction of blood cells and haemorrhage).

Stone fish is a true fish. It belongs to the class Pisces of phylum Chordata.

Ecdysis is the moulting of the cuticle in many invertebrates. Moulting is the defining feature of Ecdysozoa, comprising the arthropods, nematodes, velvet worms, horsehair worms, tardigrades and Cephalorhyncha. Since the cuticle of these animals typically forms a largely inelastic exoskeleton, it is shed during growth and a new, larger covering is formed.

It is an echinoderm which has radial symmetry in adult phase and bilateral symmetry in the larval stage.

It is a lizard like semi-terrestrial nocturnal amphibian. It belongs to the class Urodela.

It is the sole representative of the Palaeozoic group of molluscs. It is also known as a living fossil.

The study of lizards is called saurology.

It is the fastest flying arthropod.

Ichthyophis or blind worm is a limbless amphibian that lives in small burrows in moist soil, generally near tropical and subtropical areas of India and other South Asian countries. 

Archaeopteryx lithographia or the lizard bird is an extinct primitive bird that lived on earth about 150 million years ago.