Larva vs Pupa
Larva and pupa are two life stages found in insects during their life cycle. These stages are sequential, but with many differences. Going through several stages like this is called metamorphosis. It is a common feature of modern insects. Insects are the only invertebrates with wings, which enable them to fly. This capability has made them survive under different conditions and live in many habitats in the world. Metamorphosis, however, enables them to utilize many different sets of resource s during their life. Two types of metamorphosis are found in insects; (a) incomplete metamorphosis, during which eggs hatch into nymphs that gradually turn to adults (eg: cockroaches. grasshoppers and dragonflies), and (b) complete metamorphosis, where larva and pupa are found between egg and adult stage (eg: beetles, wasps, ants, bees, etc.) .
What is Larva?
Larva is the first active stage of an insect’s life cycle and it begins once the eggs are hatched. The main purpose of having a larval stage may be to feed and gather energy, which is utilized in its subsequent life stages. Usually most insects spend their life as a larvae, because it is the most productive stage in their life cycle. The adult’s only purpose is the reproduction and passing their gene to the next generation. Thus, most of them mainly rely on the energy that they have gained during the larval stage. For example, the adult of rosy maple moth never eats and entirely relies on energy which has been stored during its larval stage. When compared to other stages, larval stage of insects can cause very high damages to crops. Some common larval forms include grub worm, inchworm, maggot and caterpillar.
What is Pupa?
Pupa is the stage between larva and adult. Outside, it usually appears as a dark, still, hardened mass. However, inside it is continuously transforming to the adult stage. During this transformation process, first the larval cells are broken into undifferentiated cells. These undifferentiated cells are then differentiated into cells which eventually form the new physical form. Pupa usually does not feed and is motionless. Unless larva lives in a stem or root, it constructs a protective shell called cocoon. The cocoons are usually built from soil particles, silk, chewed seeds, plant materials, ground litter or combinations of these materials.
What is the difference between Larva and Pupa?
• During the incomplete metamorphosis, larva is followed by pupa, whereas pupa is followed by adult stage.
• Larval stage begins soon after an egg hatches, whereas pupa is formed from larva.
• Larva is more active than pupa.
• Usually larva causes huge damages to agricultural crops than pupa.
• Unlike larva, pupa usually lives in an enclosed case called cocoon.