| Agapostemon (Agapostemon) angelicus Cockerell, 1924 | |
| Agapostemon (Agapostemon) femoratus Crawford, 1901 | |
| Agapostemon (Agapostemon) obliquus Provancher, 1888 | |
| Agapostemon (Agapostemon) texanus Cresson, 1872 | Green sweat bee |
| Agapostemon (Agapostemon) virescens Fabricius, 1775 | Bicolored Agapostemon |
| Andrena (Andrena) frigida Smith, 1853 | Frigid Andrena |
| Andrena (Callandrena) fulvipennis Smith, 1853 | Stout tagelus |
| Andrena (Callandrena) utahensis LaBerge, 1967 | |
| Andrena (Cnemidandrena) colletina Cockerell, 1906 | |
| Andrena (Diandrena) agoseridis Thorp, 1969 | |
| Andrena (Euandrena) auricoma Smith, 1879 | Bunchberry dogwood |
| Andrena (Melandrena) cerasifolii Cockerell, 1896 | |
| Andrena (Micrandrena) illinoiensis Robertson, 1891 | |
| Andrena (Micrandrena) melanochroa Cockerell, 1898 | Rose Miner Bee |
| Andrena (Micrandrena) piperi Viereck, 1904 | |
| Andrena (Onagrandrena) apacheorum Cockerell, 1897 | |
| Andrena (Plastandrena) argemonis Cockerell, 1896 | Prickly-poppy Andrena |
| Andrena (Scaphandrena) scurra Viereck, 1904 | |
| Andrena (Simandrena) angustitarsata Viereck, 1904 | |
| Andrena (Thysandrena) candida Smith, 1879 | Bunchberry dogwood |
| Andrena (Thysandrena) w-scripta Viereck, 1904 | W-Marked Miner Bee |
| Andrena (Trachandrena) amphibola Viereck, 1904 | |
| Andrena (Trachandrena) striatifrons Cockerell, 1897 | |
| Andrena (Tylandrena) hallii Dunning, 1898 | |
| Anthophora (Heliophila) abroniae Timberlake, 1937 | |
| Anthophora (Heliophila) peritomae Cockerell, 1905 | |
| Anthophora (Lophanthophora) neglecta Timberlake &..., 1936 | |
| Anthophora (Lophanthophora) porterae Cockerell, 1900 | |
| Anthophora (Lophanthophora) ursina Cresson, 1869 | |
| Anthophora (Melea) bomboides Kirby, 1837 | Bumble-bee-mimic Anthophora |
| Anthophora (Melea) occidentalis Cresson, 1869 | Digger bee |
| Anthophora (Mystacanthophora) montana Cresson, 1869 | Rocky Mountain Anthophora |
| Anthophora (Mystacanthophora) urbana Cresson, 1878 | |
| Anthophorula (Anthophorula) gutierreziae Timberlake, 1947 | |
| Apis (Apis) mellifera Linnaeus, 1758 | Drone-Bee |
| Ashmeadiella (Ashmeadiella) gillettei Titus, 1904 | |
| Astata occidentalis Cresson, 1881 | |
| Augochlora (Augochlora) pura Say, 1837 | Augochlora Sweat Bee |
| Augochlorella aurata Smith, 1853 | Golden Sweat Bee |
| Augochlorella persimilis Viereck, 1910 | |
| Augochloropsis (Paraugochloropsis) metallica Fabricius, 1793 | Green Metallic Sweat Bee |
| Bembix occidentalis Fox, 1893 | |
| Bombus (Bombus) nevadensis Cresson, 1874 | Nevada bumble bee |
| Bombus (Bombus) occidentalis (Greene, 1858) | ⇒ Bombus terricola Kirby, 1837 |
| Bombus (Cullumanobombus) rufocinctus Cresson, 1863 | Red-belted Bumble Bee |
| Bombus (Fervidobombus) fervidus Fabricius, 1798 | Golden Northern Bumble Bee |
| Bombus (Fervidobombus) pensylvanicus De Geer, 1773 | American bumble bee |
| Bombus (Psithyrus) insularis (Smith, 1861) | ⇒ Bombus hypnorum Linnaeus, 1758 |
| Bombus (Pyrobombus) bifarius Cresson, 1878 | Black-notched Bumble Bee |
| Bombus (Pyrobombus) centralis Cresson, 1864 | Central bumble bee |
| Bombus (Pyrobombus) flavifrons Cresson, 1863 | Yellow head bumble bee |
| Bombus (Pyrobombus) huntii Greene, 1860 | Hunt bumble bee |
| Bombus (Pyrobombus) melanopygus Nylander, 1848 | Black tail bumble bee |
| Bombus (Pyrobombus) mixtus Cresson, 1878 | Fuzzy-horned bumble bee |
| Bombus (Pyrobombus) sylvicola Kirby, 1837 | Forest bumble bee |
| Bombus (Pyrobombus) ternarius Say, 1837 | Orange-belted Bumble Bee |
| Bombus (Pyrobombus) vosnesenskii Radoszkowski, 1862 | Vosnesensky bumble bee |
| Bombus (Separatobombus) griseocollis (DeGeer, 1773) | ⇒ Bombus griseocollis De Geer, 1773 |
| Bombus (Separatobombus) morrisoni (Cresson, 1878) | ⇒ Bombus morrisoni Cresson, 1878 |
| Calliopsis (Calliopsima) coloradensis Cresson, 1878 | |
| Calliopsis (Micronomadopsis) australior Cockerell, 1897 | |
| Calliopsis (Micronomadopsis) helianthi Swenk & Cock..., 1907 | Euphorbia Nomadopsis |
| Ceratina (Zadontomerus) pacifica H. S. Smith, 1907 | |
| Ceratina (Zadontomerus) sequoiae Michener, 1936 | |
| Clypeadon laticinctus Cresson, 1865 | |
| Coelioxys (Acrocoelioxys) producta Cresson, 1865 | |
| Coelioxys (Boreocoelioxys) octodentata Say, 1824 | Eight-toothed Cuckoo-leaf-cutter |
| Coelioxys (Coelioxys) sodalis Cresson, 1878 | Comrade Cuckoo Leafcutter Bee |
| Coelioxys (Xerocoelioxys) grindeliae Cockerell, 1900 | |
| Colletes bryanti Timberlake, 1951 | Bryant´s Cellophane Bee |
| Colletes gypsicolens Cockerell, 1897 | |
| Colletes lineatus Metz, 1910 | |
| Colletes phaceliae Cockerell, 1906 | Phacelia Cellophane Bee |
| Diadasia (Coquillettapis) diminuta Cresson, 1878 | |
| Diadasia (Coquillettapis) lutzi Cockerell, 1924 | |
| Diadasia (Dasiapis) ochracea Cockerell, 1903 | Ochraceous Chimney Bee |
| Diadasia (Diadasia) enavata Cresson, 1872 | Sunflower Chimney Bee |
| Dianthidium (Dianthidium) curvatum Smith, 1854 | |
| Dianthidium (Dianthidium) subparvum Swenk, 1914 | |
| Dieunomia (Dieunomia) heteropoda Say, 1824 | Black-and-yellow cuthona |
| Dieunomia (Epinomia) nevadensis Cresson, 1874 | Nevada Nomia |
| Dufourea marginata Cresson, 1878 | |
| Elaphropoda bembidion Lieftinck, 1966 | Cascade cave amphipod |
| Eucerceris rubripes Cresson, 1879 | |
| Eucerceris vittatifrons Cresson, 1879 | |
| Exomalopsis (Stilbomalopsis) solani Cockerell, 1896 | Solanum Exomalopsis |
| Exomalopsis (Stilbomalopsis) solidaginis Cockerell, 1898 | |
| Halictus (Monilapis) confusus Smith, 1853 | Confusing Furrow Bee |
| Halictus (Nealictus) farinosus (Smith, 1853) | ⇒ Halictus farinosus Smith, 1853 |
| Halictus (Odontalictus) ligatus Say, 1837 | Ligated Furrow Bee |
| Halictus (Seladonia) tripartitus Cockerell, 1895 | |
| Heriades (Neotrypetes) texanus (Michener, 1938) | ⇒ Heriades texana Michener, 1938 |
| Heriades (Neotrypetes) timberlakei Michener, 1938 | |
| Hesperapis (Disparapis) arenicola Crawford, 1917 | |
| Hoplisoides tricolor Cresson, 1868 | |
| Hoplitis (Monumetha) albifrons Kirby, 1837 | White-Fronted Small-Mason |
| Hylaeus (Hylaeus) mesillae Cockerell, 1896 | Mesilla Masked Bee |
| Larropsis (Larropsis) arizonensis Bohart & Bohart, 1966 | |
| Lasioglossum (Dialictus) albohirtum Crawford, 1907 | |
| Lasioglossum (Dialictus) hudsoniellum Cockerell, 1919 | |
| Lasioglossum (Dialictus) hyalinum Crawford, 1907 | |
| Lasioglossum (Dialictus) incompletum Crawford, 1907 | |
| Lasioglossum (Dialictus) occidentale Crawford, 1902 | |
| Lasioglossum (Dialictus) perdifficile Cockerell, 1895 | |
| Lasioglossum (Dialictus) pruinosiforme (Crawford, 1906) | ⇒ Lasioglossum semicaeruleum Cockerell, 1895 |
| Lasioglossum (Dialictus) pruinosum Robertson, 1892 | Hoary Sweat Bee |
| Lasioglossum (Hemihalictus) ovaliceps Cockerell, 1898 | |
| Lasioglossum (Lasioglossum) paraforbesii McGinley, 1986 | |
| Lasioglossum (Lasioglossum) sisymbrii Cockerell, 1895 | |
| Lasioglossum (Lasioglossum) trizonatum Cresson, 1874 | |
| Lasioglossum lasioglossum Strand, 1913 | |
| Lasioglossum pulveris Cockerell, 1930 | |
| Lasioglossum sedi Sandhouse, 1924 | |
| Liris beatus Cameron, 1889 | |
| Macrotera latior Cockerell, 1896 | |
| Megachile (Argyropile) parallela Smith, 1853 | Parallel Leaf-cutter Bee |
| Megachile (Litomegachile) brevis (Say, 1837) | ⇒ Megachile pseudobrevis Mitchell, 1934 |
| Megachile (Litomegachile) coquilletti Cockerell, 1915 | |
| Megachile (Litomegachile) gentilis Cresson, 1872 | Leafcutter bee |
| Megachile (Litomegachile) lippiae Cockerell, 1900 | |
| Megachile (Litomegachile) texana Cresson, 1878 | Texas Leaf-cutter Bee |
| Megachile (Neoeutrichaea) rotundata Fabricius, 1793 | Alfalfa leaf-cutter bee |
| Megachile (Sayapis) policaris Say, 1831 | |
| Megachile (Xanthosarus) comata Cresson, 1872 | |
| Megachile (Xanthosarus) melanophaea Smith, 1853 | Black-and-gray Leaf-cutter Bee |
| Megachile (Xanthosarus) perihirta Cockerell, 1898 | Furry Leaf-cutter Bee |
| Megachile chelostomoides Gribodo, 1894 | |
| Melecta (Melecta) pacifica Cresson, 1878 | |
| Melissodes (Callimelissodes) glenwoodensis Cockerell, 1905 | |
| Melissodes (Callimelissodes) lupina Cresson, 1878 | |
| Melissodes (Eumelissodes) agilis Cresson, 1878 | Agile Long-horned Bee |
| Melissodes (Eumelissodes) bimatris LaBerge, 1961 | |
| Melissodes (Eumelissodes) coreopsis Robertson, 1905 | Subterranean clover |
| Melissodes (Eumelissodes) fasciatella LaBerge, 1961 | |
| Melissodes (Eumelissodes) lutulenta LaBerge, 1961 | |
| Melissodes (Eumelissodes) montana Cresson, 1878 | |
| Melissodes (Eumelissodes) subagilis Cockerell, 1905 | |
| Melissodes (Eumelissodes) tristis Cockerell, 1894 | |
| Melissodes (Eumelissodes) utahensis LaBerge, 1961 | |
| Melissodes (Heliomelissodes) rivalis Cresson, 1872 | |
| Melissodes (Tachymelissodes) dagosa Cockerell, 1909 | |
| Neolarra vigilans Cockerell, 1895 | |
| Nomada vegana (Cockerell, 1903) | ⇒ Nomada modesta Cresson, 1863 |
| Osmia (Cephalosmia) montana Cresson, 1864 | |
| Osmia (Chenosmia) cobaltina Cresson, 1878 | |
| Osmia (Melanosmia) albolateralis Cockerell, 1906 | |
| Osmia (Melanosmia) brevis Cresson, 1864 | |
| Osmia (Melanosmia) bruneri Cockerell, 1897 | |
| Osmia (Melanosmia) cyanella Cockerell, 1897 | |
| Osmia (Melanosmia) densa Cresson, 1864 | |
| Osmia (Melanosmia) gaudiosa Cockerell, 1907 | |
| Osmia (Melanosmia) juxta Cresson, 1864 | |
| Osmia (Melanosmia) simillima Smith, 1853 | Similar Mason Bee |
| Osmia (Osmia) lignaria Say, 1837 | Blue orchard bee |
| Osmia (Pyrosmia) pusilla Cresson, 1864 | |
| Osmia bella (Cresson, 1878) | ⇒ Osmia cobaltina Cresson, 1878 |
| Osmia pentstemonis Cockerell, 1906 | |
| Osmia trevoris Cockerell, 1897 | |
| Oxybelus cornutus Robertson, 1889 | |
| Oxybelus emarginatus Say, 1837 | Vegetable hummingbird |
| Oxybelus sericeus Robertson, 1889 | |
| Oxybelus uniglumis Linnaeus, 1758 | Common Spiny Digger Wasp |
| Perdita (Cockerellia) albipennis Cresson, 1868 | White-winged Perdita |
| Perdita (Cockerellia) lingualis Cockerell, 1896 | |
| Perdita (Perdita) gutierreziae Cockerell, 1896 | |
| Perdita (Perdita) luteola Cockerell, 1894 | |
| Perdita (Perdita) melanostoma Swenk & Cock..., 1907 | |
| Perdita (Perdita) mentzeliae Cockerell, 1896 | |
| Perdita (Perdita) phymatae Cockerell, 1895 | |
| Perdita (Perdita) rhodura Cockerell, 1897 | |
| Perdita arizonica Timberlake, 1956 | |
| Perdita dubia Cockerell, 1896 | |
| Perdita plucheae Timberlake, 1960 | |
| Perdita truncatella Timberlake, 1968 | |
| Philanthus crabroniformis (Smith, 1856) | ⇒ Philanthus multimaculatus Cameron, 1891 |
| Philanthus gibbosus Fabricius, 1775 | Bee wolf |
| Philanthus multimaculatus Cameron, 1891 | |
| Philanthus psyche Dunning, 1896 | |
| Philanthus ventilabris Fabricius, 1798 | Bee-killer wasp |
| Protandrena sphaeralceae Timberlake, 1976 | |
| Protosmia (Chelostomopsis) rubifloris Cockerell, 1898 | |
| Pseudopanurgus (Pseudopanurgus) aethiops Cresson, 1872 | |
| Pseudopanurgus fraterculus Cockerell, 1896 | |
| Sphex ichneumoneus Linnaeus, 1758 | Great Golden Digger |
| Stelis (Stelidium) ashmeadiella | |
| Stelis (Stelis) montana Cresson, 1864 | |
| Tachysphex ashmeadii Fox, 1894 | |
| Tachysphex tarsatus Say, 1823 | |
| Tachysphex texanus Cresson, 1873 | |
| Tachytes spatulatus Fox, 1892 | |
| Tetraloniella (Tetraloniella) eriocarpi Cockerell, 1898 | |
| Tetraloniella (Tetraloniella) imitatrix Cockerell & ..., 1899 | |
| Trachusa (Heteranthidium) occidentalis Cresson, 1868 | |
| Trachusa (Heteranthidium) zebrata Cresson, 1872 | |
| Triepeolus distinctus Cresson, 1878 | |
| Triepeolus grindeliae Cockerell, 1907 | |
| Triepeolus helianthi Robertson, 1897 | Sunflower Cuckoo Nomad Bee |
| Trigonopsis cyclocephala F. Smith, 1873 | |
| Xeromelecta (Melectomorpha) californica Cresson, 1878 | California Xeromelecta |
| Xylocopa (Xylocopoides) californica Cresson, 1864 | California carpenter bee |
