Pollen-specialization
Guides
Calliopsis
mining bees, panurgine bees
Calliopsis is a genus of solitary mining bees in the family Andrenidae, comprising over 80 described species distributed throughout the western hemisphere. These small to medium-sized bees are ground-nesting, with females excavating burrows in sandy or loose soils. The genus includes both polylectic and oligolectic species, with some showing tight specialization to particular pollen hosts such as Prosopis. Several species have been studied in detail for their nesting biology, foraging behavior, and host-parasite relationships with cleptoparasitic bees.
Emphorini
Chimney Bees
Emphorini is a tribe of solitary, ground-nesting bees within the family Apidae. Members are characterized by narrow pollen preferences, with many species exhibiting oligolecty (specialized pollen collection from a restricted range of plant taxa). Nesting behavior varies: some species carry water to soften hard soil during excavation, while others do not. The tribe includes approximately nine genera distributed primarily in the New World, with an amphitropical distribution pattern in some genera.
Macrotera
Goblin Bees
Macrotera is a genus of mining bees (Andrenidae) native to North America, with approximately 30 species. These bees range from 2.0 to 16.0 mm in body length and are predominantly found in desert regions of the United States and Mexico. The genus was segregated from Perdita by C.D. Michener in 2000. Most species exhibit extreme pollen specialization (oligolecty), with documented associations to Sphaeralcea and Cactaceae.
Osmiini
mason bees, leafcutter bees, resin bees
Osmiini is a tribe of solitary bees within the family Megachilidae, comprising approximately 19 genera and at least 1,000 described species. Members are commonly known as mason bees, leafcutter bees, and resin bees, reflecting their diverse nest construction behaviors. The tribe exhibits considerable diversity in nesting ecology, with species utilizing preexisting cavities in dead wood, hollow stems, rock crevices, empty snail shells, or excavated soil burrows. Nesting materials vary by lineage and include chewed leaves, mud, resin, and combinations with pebbles or sand grains. Pollen foraging strategies range from strict oligolecty on single plant genera or families to broad generalization across numerous plant families.
Panurginae
Panurginae is a subfamily of solitary bees within family Andrenidae, comprising 33 genera in 7 tribes. The group is particularly diverse in the New World, with greatest representation in arid and temperate regions, and occurs in the Palearctic and Africa in the Old World. Members are strongly associated with xeric and sandy habitats. Most species are oligolectic, exhibiting specialized pollen-foraging relationships with particular host plants.