Bruco

Bruco is the Italian term for the larval stage of Lepidoptera, encompassing the caterpillars of butterflies and moths. In everyday use, it refers to these worm-like, often legged caterpillars that feed and grow before metamorphosing into adult insects.

Bruchi typically have elongated, segmented bodies with multiple legs near the head and additional leg-like structures called prolegs along the abdomen. Their coloration and markings vary widely, often providing camouflage or warning signals to predators. Most bruco are herbivorous, feeding on leaves, flowers, or stems of plants, sometimes showing strong host preferences.

The life cycle of a bruco begins when an egg laid on a plant hatches into a larva. The bruco then molts several times as it increases in size, before entering a pupal stage—crysalis in butterflies or a cocoon in many moths—through which it later emerges as an adult butterfly or moth. This complete metamorphosis is characteristic of Lepidoptera.

Ecologically, bruco play a crucial role as primary herbivores and as a food source for other animals. Some species are important agricultural pests, capable of damaging crops and ornamental plants. Conversely, many bruco contribute to ecosystems without causing economic harm, and they are often studied in biological and ecological research. Management of pest bruco commonly involves integrated pest management strategies, including biological controls and targeted interventions.

Notable examples include the monarch butterfly larva (Danaus plexippus), which feeds on milkweed, and agricultural pests such as the cabbage looper (Trichoplusia ni) and the fall armyworm (Spodoptera frugiperda). The term bruco highlights the larval stage across diverse species within Lepidoptera.