Cliff Mason Bee vs Common Least Skipper

Osmia xanthomelana compared with Ancyloxypha numitor

Key Differences

• Cliff Mason Bee is Not Evaluated while Common Least Skipper is Least Concern.

Taxonomic Classification

Rank	Cliff Mason Bee	Common Least Skipper
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Arthropoda (Arthropods)	Arthropoda (Arthropods)
Class same	Insecta (Insects)	Insecta (Insects)
Order	Hymenoptera (Ants, Bees & Wasps)	Lepidoptera (Butterflies & Moths)
Family	Megachilidae	Hesperiidae
Genus	Osmia	Ancyloxypha
Species	Osmia xanthomelana	Ancyloxypha numitor

Evolutionary Relationship

Cliff Mason Bee and Common Least Skipper share a common ancestor at the Class level: Insecta. (Insects)

Conservation Status

Cliff Mason Bee

NE — Not Evaluated

Common Least Skipper

LC — Least Concern

Physical Characteristics

Attribute	Cliff Mason Bee	Common Least Skipper
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Cliff Mason Bee

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Denmark, Luxembourg, and Sweden.

Common Least Skipper

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Canada and United States.

Cliff Mason Bee

The Cliff Mason Bee, Osmia species, is one of numerous solitary bees in the large genus Osmia, family Megachilidae, whose females construct individual brood cells from mud, clay, or resin in crevices on cliff faces, rock walls, and outcrops. Mason bees are important pollinators of wildflowers and orchard crops, collecting pollen and nectar to provision their nests. Cliff mason bees take advantage of natural crevices in rock faces as nesting sites, plastering cells of mud mixed with sand grains or plant material to subdivide the crevice into individual egg chambers. Each cell contains a pollen-nectar mass food provision and a single egg before being sealed with a mud plug. Males typically emerge first in spring, followed by females, and adults live for only several weeks, devoted entirely to mating and nesting. Cliff-nesting Osmia species are found in rocky habitats across the Holarctic region, from Europe through Asia and North America. The availability of suitable nesting sites on cliff faces, combined with the proximity of diverse wildflower resources, determines population density. Many solitary bee populations have declined in recent decades due to loss of nesting habitat and floral resources. Specific conservation status depends on the species intended.

Common Least Skipper

The Common Least Skipper (<em>Ancyloxypha numitor</em>) is a small butterfly in the family Hesperiidae, classified as Least Concern on the IUCN Red List. It is native to Canada and the United States, where it typically inhabits virtually all terrestrial and freshwater habitats within its range, showing a particular affinity for moist, grassy areas near water. The species is among the smallest skippers in North America, characterized by orange and brown wing coloration and a rapid, low-flying flight pattern close to vegetation. Adults typically nectar on small flowers while larvae feed on grasses, particularly those in wet meadows, marshes, stream margins, and disturbed grassy areas. The Common Least Skipper is frequently observed in wetland margins, wet prairies, and roadsides with rank grass growth. Its wide distribution across North America and habitat generalism across moist grassland and wetland types support its stable population and Least Concern conservation status. Biological traits of this species remain poorly documented in the scientific literature.