Like almost all lepidopteran species, moths have a tongue or proboscis specially adapted for sucking. Moths visit plants with pale or white flowers; these usually diffuse abundant fragrance and offer dilute nectar. Moths do not always stand on flowers: sometimes they suck nectar while hovering on them. They also rest on flowers, landing on their surface. The bodies of moths are furry, and they carry pollen on the fur, where pollen is trapped during resting, as well as on their tongue, where pollen sticks when they are feeding.
Butterflies visit a wide range of flowers, preferring brightly coloured blooms (red, yellow, orange), and they fly during warm weather. They are perching feeders, therefore flowers need to offer them a landing platform. Butterflies have the tendency to visit a few flowers on a plant and then fly to another: this makes them good pollen vectors, as they can carry pollen long distances. This facilitates cross-pollination (i.e. pollination between different individuals of the same plant species) and ensures a good mixture of genes.
Bee flies (Bombyliidae) are fewer in species compared to hoverflies, nevertheless they are keen visitors to flowers and some of them important pollinators. Their name reveals their appearance –they look like bees, due to their hairy body and in fact some of them are bee mimics. Most of the species are parasitoids of other insects, suggesting that their larvae do not depend on flowers; the adults of many species do, however: their mouthparts modified for sucking nectar from deep flowers may be as long as four times the length of the head of the insect.
The most important family of flies is that of Syrphidae, also known as hoverflies or flower flies, the latter name highlighting their special relationship with flowering plants. Within the Mediterranean, the family encompasses more than 500 species varying as to their dependence on flowers and pollination efficiency. Only adults visit the flowers for nectar and pollen, which implies that no hoverfly species is exclusively dependent on flowers, as the larvae may be phytophages, saproxylics, microphages or predators.
Beetles are considered as primitive pollinators and this has a dual sense. First, among the main pollinator guilds, beetles have been the earliest on the earth to visit systematically flowers and carry over pollen. Second, and as a consequence of the fact that their primeval flower-related characters have little changed since, their primitiveness is recognizable from their body anatomy and their flower-visiting behavior. In the Mediterranean region they are present particularly in the dry months, their massive presence on the flowers denoting the onset of summer drought.
Wasps are a diverse group of insects with different forms of life. Some are eusocial and live in colonies, but most are solitary species. There are many families and subgroups of wasps in the world. In the Mediterranean region, the most important are the cuckoo wasps (Chrysididae), the spider wasps (Pompilidae), Scoliidae, Sphecidae, and the vespids (Vespidae).
Bees are the largest group of pollinators. They evolved in strict conjunction with flowers. All the food they need comes from flowers. Bees’ bodies are covered with hair - this is very helpful to trap as much pollen as possible. There are structures precisely evolved to pollen collection, and bee activity is very much concentrated on flower visitation.