Oreopasites

Members of Oreopasites can be distinguished from other Ammobatini by their relatively small size and specific structural features of the male genitalia, which are diagnostic at the genus level. Females lack pollen-collecting structures (scopa), consistent with their cleptoparasitic lifestyle. Detailed identification to species level requires examination of subtle morphological characters including punctation patterns and genitalic structures.

Species of Oreopasites are associated with arid and semi-arid environments in western North America, including desert scrub, chaparral, and dry grassland ecosystems. They are typically found in areas where their host bees nest in the ground.

Western North America, with records from the southwestern United States (Arizona, California, Nevada, New Mexico, Texas, Utah) and adjacent regions of Mexico.

• Ammobatoides - hostSpecies in the genus Ammobatoides are the primary hosts for Oreopasites; the parasitic relationship is specific at the genus level.

As cleptoparasitic bees, females lay eggs in the nests of host bees. Larvae develop by consuming the host's pollen provisions and often the host egg or larva. Developmental details specific to Oreopasites are poorly documented.

Females are known to enter host nests to deposit eggs, a behavior characteristic of cleptoparasitic bees. Males have been observed patrolling areas near host nesting aggregations.

As kleptoparasites, Oreopasites function as population regulators of their host bees. They contribute to bee community dynamics by exerting selective pressure on host nesting behavior and population sizes.

Oreopasites has no direct economic importance. The genus is of interest to bee systematists and conservation biologists studying bee community structure and parasitic relationships in western North American ecosystems.

• AmmobatesAlso in tribe Ammobatini and similar in size and general appearance; distinguished by male genitalic structure and female facial markings.
• AmmobatoidesHost genus that resembles Oreopasites in size and habitat preference; distinguished by presence of scopa in females and non-parasitic nesting behavior.
• NomadaLarger genus of cuckoo bees in subfamily Nomadinae with similar cleptoparasitic lifestyle; distinguished by generally larger size, more extensive yellow or red markings, and different wing venation.

• cuckoo bee
• kleptoparasite
• Ammobatini
• western North America
• bee parasite

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life