Megachile

The genus Megachile is a large group of solitary bees, often called leafcutter bees or leafcutting bees. These bees are found all over the world. Unlike some other bees that might chew leaves or petals into pieces, certain species in Megachile carefully cut neat pieces of leaves or petals, which gives them their common name.

This is one of the largest bee groups, with more than 1500 species divided into over 50 subgroups. One special species, the alfalfa leafcutter bee (Megachile rotundata), is very important for helping plants grow. People carefully manage these bees to help pollinate crops, and they have been moved to many parts of the world to help with this important work.

Ecology

Megachile bees, often called leafcutter bees, build their nests in hollow twigs or burrows in the ground. Inside these nests, they create long columns of cells. Each cell holds an egg and a supply of food, usually pollen mixed with nectar. After laying an egg, the female seals the cell. The baby bee, called a larva, eats the food, grows, and eventually turns into a cocoon. After resting for a while, it becomes an adult bee.

Some Megachile bees cut pieces of leaves to line their nest cells, which helps keep the food fresh. Others use dry plant resin instead of leaves. These bees are very interesting because some species were the first insects known to use human-made materials to build their nests.

Diversity

The group Megachile has 56 subgroups and 1,520 known species. Some well-known sub-groups include Callomegachile, Chalicodoma, and Chelostomoides.

Famous species in this group are Megachile albisecta, Megachile aurifrons (the red-eyed bee), Megachile campanulae (the bellflower resin bee), Megachile erythropyga, Megachile fidelis (the faithful leafcutting bee), Megachile nigrovittata, Megachile perihirta (the western leafcutting bee), Megachile pluto (the largest bee in the world), Megachile rotundata (the alfalfa leafcutter bee), Megachile rubi, Megachile sculpturalis (the giant resin bee), and Megachile texana (the Texas leafcutter bee). You can see the full list of Megachile species here.