The carnivorous plants have extraordinary adaptations to environmental conditions deficient in nutrients. These plants compensate the acid soil, poor in nitrogen, phosphorus, and potassium in which they grow by digesting small animals, usually insects. An impressive number of plant species, c. 500, have developed traps that retain small animals and keep them in contact with the juices they secrete highly concentrated in digestive enzymes. These break down the animals' bodies and the plant absorbs the elements through the epidermis. Some traps are relatively simple, as the glandular epidermal hairs that secrete both enzymes and sticky mucilage that glues the animal, but there are also complex structures such as the specialized leaves in the shape of wells that accumulate the plant's secretions. There are also leaves that quickly close or suck the animals, trapping them. Most carnivorous species grow in moist habitats and are threatened. Their research is important for the preservation of these unique and very rich habitats.
There are c. 12 genera of carnivorous plants, but only four are found in Portugal, Drosera, Drosophyllum, Pinguicula and Utricularia.
Get to know them by transcribing the information on the labels of herbarium specimens of the University of Coimbra.