How many body parts does a butterfly have?
Like other insects, moths and butterflies have four wings, six legs, and a jointed body divided into three sections—head, thorax, and abdomen. Perhaps the most distinctive physical features of the butterfly are its club-tipped antennae and its habit of holding the wings vertically over the back when at rest. The wings, bodies, and legs, like those of moths, are covered with dustlike scales.
All the body parts of the butterfly include:
- Forewings
- Posterior (hind) wings
- Antennae
- Head
- Thorax
- Abdomen
- Compound Eyes
- Proboscis
- Forelegs
- Middle pair of legs
- Hind legs.
- Spiracles
- Digestive Tract
Wings
A butterfly has four wings, two forewings and two hindwings. They are attached to the second and third thoracic segments (the meso- and meta-thorax). Strong muscles in the thorax move the wings up and down in a figure-eight pattern during flight. Covering the wings are thousands of colorful scales, together with many hairs (setae).
When the fully-grown adult butterfly emerges from its pupa, its delicate wings are crinkled, wet, and uninflated. The butterfly hangs upside-down and pumps blood into the wings to inflate them. It must then wait for the wings to dry before it can fly. When the fragile wings fray or are torn, they do not repair themselves.
Forewings and hindwings
The upper wings, called the forewings, and the lower wings, called the hindwings, are both very fragile. Although they are strong enough to support the butterfly’s body in the air, they are also flexible to enable flight.
Antennae
Antennae are sensory organs that help an insect perceive and navigate their environment. They are very clever organs that are like a mix of human fingers and noses, allowing insects to understand a lot about their environment.
Butterflies have antennae attached to their heads. These are used to help them balance, especially while they are flying, and to smell the world around them.
Butterflies have two antennae that are broken into segments. Each butterfly antenna has a small club at its end. Butterfly antennae are very clever. They work along with sensors on their feet as essential tools which help them with navigation, finding food and their friends, and telling the time of day. If a butterfly loses an antenna, it doesn’t die. Its senses are weakened.
Head
The butterfly’s head is the location of its feeding and sensory structures. The almost spherical head contains its brain, two compound eyes, its proboscis, pharynx (the start of the digestive system), the point of attachment of its two antennae, Johnston’s organ, mustache-like sensory palps, etc.
Thorax
The thorax is the locus for locomotion. The thorax consists of only three jointed segments, the prothorax, mesothorax, and metathorax, each derives from a primitive segment. In each segment of the thorax, there is a pair of jointed legs. Thorax also bears two pairs of wings, a pair of forewings, and a pair of hindwings. The thorax contains the muscles that make the legs and wings move.
Abdomen
The abdomen is the cone-shaped section of the butterfly’s body. In other words, it is the middle section of a butterfly’s body, occurring between the head and abdomen. The abdomen is relatively soft and is divided into 10 segments (7-8 are easily seen, the others are fused). At the end of the abdomen are the reproductive organs; in the male, there is a pair of claspers, which are used to hold on to the female during mating. In the female, the abdomen contains a tube made to lay eggs.
Johnston’s organ
Johnston’s organ is an organ located at the base of a butterfly’s antennae. This organ are responsible for maintaining the butterfly’s sense of balance and orientation, especially during flight.
Compound Eyes
Butterflies have a pair of spherical compound eyes, each comprising of up to 17000 ommatidia, individual light receptors with their own microscopic lenses. These work in unison to produce a mosaic view of the scene around them.
In other words, the compound Eyes in butterfly are responsible for providing their all round vision. They have four classes of receptors which are responsible for their wide visual range. These eyes are also used for sensing Ultraviolet color and polirized light.
Butterflies can see everything from about one centimeter to 650 feet will be rendered in sharp focus, as their ommatidia are of very short focal length.
Palps
Palps are the mustache-like scaly mouthparts of adult butterflies that are on each side of the proboscis. These palps are covered with sensory hairs and scales, and test whether something is food or not.
Spiracles
Spiracles are the mechanism through which butterflies take in oxygen and expel carbon dioxide. Spiracles are located along the length of the body, but mainly focused down the sides of the abdomen. Some spiracles are dedicated to taking in oxygen, while others are used to expel carbon dioxide.
Legs
A butterfly has three legs on each side of its middle section or thorax. This insect has a pair of forelegs in the location nearest its head, next are its middle legs and finally the hind legs, each attached to a segment of the thorax. Each leg has a femur (thigh), a tibia (shin), and a tarsus (foot).
Although each typical leg consists of the standard segmented parts, there is a wide variation of the legs across the butterfly families. Legs of some butterfly species have evolved and adapted to perform a totally different function from their original purpose of locomotion (walking).
Life Cycle of a Butterfly
Butterflies have a four-stage life cycle, as like most insects they undergo complete metamorphosis. Winged adults lay eggs on the food plant on which their larvae, known as caterpillars, will feed. The caterpillars grow, sometimes very rapidly, and when fully developed, pupate in a chrysalis.
When metamorphosis is complete, the pupal skin splits, the adult insect climbs out, and after its wings have expanded and dried, it flies off. Some butterflies, especially in the tropics, have several generations in a year, while others have a single generation, and a few in cold locations may take several years to pass through their entire life cycle.