Andrena auripes

Justification:
Andrena auripes is a species known from five verified observations from northern Arizona south to Durango, Mexico. There are observations of this species that come from the species description (LaBerge 1967) that may extend the range south to Mexico City, Mexico, but these observations are over 100 years old or contain vague locality data. Using all observations with high quality locality data, the extent of occurrence (EOO) is 14,180 km2. Most observations of this species are from the 1940s and 1950s, with just one from 2010. There is little information about the biology and ecology of this species, and the bounds of its distribution are not well understood. Population size and trend are unknown. Although direct threats to this species have not been described, climate change, land use change, and low reproductive output may contribute to risk for this bee. More research is needed to determine the population trend, range, and threats to this species. As such, it is listed as Data Deficient.

There is very little information about the habitat and ecology of Andrena auripes. This species likely nests underground like all other Andrena (Danforth et al. 2019), but nests for 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 before laying a single egg (Michener 2007). No records of this species include an observation of associated floral resources, so dietary preferences of Andrena auripes are not known. Observations of this species are from August and September (Chesshire et al. 2023). Adults are assumed to emerge annually (Danforth et al. 2019).

Since 2000, the Southwest U.S. has seen the worst drought in 1200 years (A. P. Williams, Cook, and Smerdon 2022). Drought can reduce the abundance of flowering plants on a landscape scale, and also reduce pollen and nectar quality (Wilson Rankin, Barney, and Lozano 2020). A recent study has shown reduced diversity and abundance of native bees under drought conditions (Hung et al. 2021). Certain aspects of this species' biology may make it more vulnerable to some threats. Andrena auripes 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 (N. M. Williams et al. 2010). 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, 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).

No known conservation actions are in place for this species. Observations of this species are known from US Forest Service 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.

More information is needed about the population status, range limits, habitat, and ecology of this species.

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