These are images of a Digger Bee or Centridine Bee, in the subgenus Paracentris, that I believe is most likely a female Red-legged Centris, Centris rhodopus.
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ID Info:
Keying to Subgenera of Genus Centris: Michener (2000) (1)
(Key to females)
1. - Secondary basitibial plate without distinct overhanging margin or with slight overhang on anterior side of plate = Subgenus Paracentris Cameron (1903)

Keying to Genera of Tribe Centridini: Snelling (1984)
Here is a link to the key, from the Natural History Museum website: Studies on the Taxonomy and Distribution of American Centridine Bees (Hymenoptera: Anthophoridae)
1. - Marginal cell of forewing shorter than distance from its apex to tip of wing; occipital flagelliform setae usually absent, but if present, not reaching as far back as anterior margin of tegula = 2
2. - Occipital flagelliform setae absent; mesosternum of female without tubercles; hypoepimeron flat or slighly convex; pronotal lobe low and moderately convex; never conspicuously tuberculate = Genus Centris Fabricus
Keying to North American Species of Subgenus Paracentris:
1. - Female, antenna 12 segmented and basitibial plate present on metatibia = 2
2. - Pubescence of head, thorax and legs entirely or predominantly pale, that of mesepisternum pale, at least in part = 7
7. - Clypeal intugement at least partially yellowish, orange or red = 11
11. - Small species, 8.5-13.5mm long; clypeus with distinct impunctate median line, punctures elsewhere separated by less than twice a puncture diameter (if clypeal punctures somewhat sparce, scape, femora and tibia ferruginous) = 12
12a. - Color of mandible, labrum and clypeus usually not as below; clypeus polished and shiny, median impunctate line present and usually well defined; tergal disks moderately to strongly shiny, with or without bluish reflections; scape, femora and tibiae brown or red = 13
12b. - Mandible (except apex), labrum and clypeus dull orange-ferruginous; clypeus usually contiguously punctate, dull and without median impunctate line, but may be moderately shiny and with narrow impuntate line; tergal disks dull and closely tesselate, with dull bluish reflections; scape femora and tibiae brown [fail] = Species ferrisi Cockerell [shown for reference, range is Mexico only]
13. - Basal face of first tergum with abundant long, plumose, white hairs, some of which extend onto dorsal face in middle; terga with definite bluish reflections = 14
14. - Mandible, labrum, clypeus, scape, femora and tibiae mostly or entirely bright ferruginous; apical margins of second and third terga with short bands of appressed pale hairs; first flagellar segment shorter than following three combined = Species rhodopus Cockerell