Anthidium is a genus of bees often called mason or potter bees, who use conifer resin, plant hairs, mud, or a mix of them to build nests. They are in the family Megachilidae which is cosmopolitan in distribution and made up of species that are mostly solitary bees with pollen-carrying scopea that are only located on the ventral surface of the abdomen. Other bee families have the pollen-carrying structures on the hind legs. Typically species of Anthidium feed on pollen and nectar from plants, though some species are robber bees that take food from other bees. Anthidium florentinum bees are distinguished from most its relatives by yellow or brick-red thoraxic bands. They fly all summer and make the nests in holes in the ground, walls or trees, with hairs plucked from plants.
Most Anthidium species are leaf-cutting bees who use conifer resin, plant hairs, earth, or a combination of these as material for the nest walls. Their abdominal bands are usually interrupted in the middle. There is no lobe (arolium) between their claws. Anthidium manicatum is commonly known as the wool carder bee which uses comblike mandibles to "comb" plant fibers into its brood cell walls. It has spread from Europe to North and South America. The males are much larger (ca. 18 mm) than the females (ca.12 mm) which is not uncommon among Megachilidae, but very rare among other bee families (e.g., the true honey bees, genus Apis). The males also have three "thorns" at their abdominal apex which they use as weapons when defending their territory.
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila. There are nearly 20,000 known species of bees in seven to nine recognized families, though many are undescribed and the actual number is probably higher. They are found on every continent except Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants.
Bees are adapted for feeding on nectar and pollen, the former primarily as an energy source and the latter primarily for protein and other nutrients. Most pollen is used as food for larvae.
Bees have a long proboscis (a complex "tongue") that enables them to obtain the nectar from flowers. They have antennae almost universally made up of 13 segments in males and 12 in females, as is typical for the superfamily. Bees all have two pairs of wings, the hind pair being the smaller of the two; in a very few species, one sex or caste has relatively short wings that make flight difficult or impossible, but none are wingless.
The smallest bee is Trigona minima, a stingless bee whose workers are about 2.1 mm (5/64") long. The largest bee in the world is Megachile pluto, a leafcutter bee whose females can attain a length of 39 mm (1.5"). Members of the family Halictidae, or sweat bees, are the most common type of bee in the Northern Hemisphere, though they are small and often mistaken for wasps or flies.