Andrena cleodora

The shiny-blue sculptured miner bee is a specialist that visits plants from the genus Ceanothus (Rhamnaceae) for pollen. Although its range covers most of the western United States, it is unlikely to occur in desert lowlands because of its tight association to its’ host plant which occurs in foothills and montane chaparral communities. This species likely nests underground like all other Andrena (Danforth et al. 2019), but nests of this species have not been described. Nest cells from other members of this genus are located at the ends of the lateral burrows, which are typically lined with a waxy Dufour’s gland secretion (Cane 1981) that serves to both isolate the provision from pathogens in the surrounding soil and to regulate water uptake from the soil atmosphere (Cane and Love 2021). Females provision each cell with a ball of pollen moistened with nectar on which they lay a single egg (Michener 2007). Records of this species range from May through July (Chesshire et al. 2023). Adults are assumed to emerge annually (Danforth et al. 2019). Habitat:

Specific threats to this species have not been identified. Alterations in the fire regime within the range of Andrena cleodora may impact this species. Its host plant, Ceanothus, can be abundant following severe wildfires (Cinoğlu et al. 2021), and in many cases, requires fire for seed germination (Quick and Quick 1961). Although large catastrophic wildfires may remove forage for A. cleodora at local levels, fire exclusion likely presents more of a threat to the bee, as Ceanothus is typically an early successional forest species and is reduced under a closed canopy (Cronemiller 1959). Certain aspects of this species' biology may make it more vulnerable to some threats. Andrena cleodora is a ground nesting species, and nests may be harmed by certain agricultural practices such as tilling, which can kill bees nesting close to the surface (Williams et al. 2010). This species is a dietary specialist, which has been linked to higher risk of extinction due to reduced host plant availability, especially under climate change scenarios (Roberts et al. 2011) and reduced effective population sizes (Packer et al. 2005). Additionally, Andrena have been reported to have low reproductive output because of the short adult life span, and a low rate of brood cell provisioning (reviewed in Danforth et al. 2019). Other threats to bees generally include habitat loss or modification, climate change, pesticide use, exposure to pathogens from managed bee species, and competition with honey bees (Brown and Paxton 2009; Potts et al. 2010; Wojcik et al. 2018; Grab et al. 2019; Raven and Wagner 2021). This species has had its conservation status evaluated using NatureServe criteria at the Canadian province level in some areas where it occurs. It has been evaluated as Vulnerable in British Columbia and Alberta.

No known conservation actions are in place for this species. Observations of this species are known from Bureau of Land Management (BLM) and United States Forest Service (USFS) land, but this does not confer any specific protections to the species. Further research is needed to determine the overall size of the population and to identify trends and better understand existing threats. Specific conservation needs for this species have not been identified. Due to the importance of supporting wild bee populations for pollination services, general conservation practices are recommended including, restoring, creating, and preserving natural high-quality habitats to include suitable forage and nesting sites; limiting pesticide use on or near suitable habitat, particularly during the adult bee’s flight period; promoting farming and urban practices that increase pollinator-friendly plants in margin space; minimizing exposure of wild bees to diseases transferred from managed bees; and lastly, avoiding honey bee introduction to high-quality native bee habitat.

(a. any taxonomic concerns about the validity of the species? b. any taxonomic revisions underway that would require a species reassessment.