Butterfly Anatomy – The Abdomen

The abdomen is made up of multiple segments made of a hard material called chitin. They are connected by flexible tissue, allowing the butterfly to move the abdomen as needed for flying and mating.

Digestion:
Butterflies are extremely efficient at digestion, leaving little behind for waste. Liquid enters through the proboscis and passes into an organ called the crop, where it is stored until digested by the midgut. During digestion nutrients from food are either absorbed into the blood or are stored as fats. Any solid waste is then excreted as frass. (Click here to learn more about frass.)

Respiration:
Butterflies breathe by drawing air in through microscopic holes called spiracles. Tiny tubes called tracheae take oxygen directly to the body tissues.

Reproductive System:
The male butterfly has a pair of claspers at the end of the abdomen used to hold onto the female abdomen during mating. The genitalia of the male and female lock together at the ends of the abdomens, and butterflies may stay attached for hours, even in flight. The genitalia of each species has a specific shape, meaning that cross-breeding between species is not physically possible.

During mating, most males provide a spermatophore, a package of sperm and nutrients the female needs to produce and lay eggs. The female butterfly then uses the ovipositor at the end of her abdomen to release the fertilized eggs onto a host plant. (Click here to learn more about mating.)