The ‘ red-tailed’ Lasioglossum (Dialictus) (Hymenoptera: Halictidae) of the western Nearctic Author Gardner, Joel AA15FE6E-921A-46D6-BC67-88E067F283D9 0000-0003-1843-466X Department of Entomology, University of Manitoba, 12 Dafoe Rd., Winnipeg, Manitoba, R 3 T 2 N 2, Canada. clickbeetle3364@gmail.com Author Gibbs, Jason BA42A49F-3EBC-4679-8F03-A58E798106B1 0000-0002-4945-5423 Department of Entomology, University of Manitoba, 12 Dafoe Rd., Winnipeg, Manitoba, R 3 T 2 N 2, Canada. jason.gibbs@umanitoba.ca text European Journal of Taxonomy 2020 2020-11-27 725 1 242 journal article 10.5852/ejt.2020.725.1167 9e062836-3946-4ac6-8910-304cadff0d4b 2118-9773 4298139 89FA8DDF-F4B9-417A-A5AF-B2BC9660E024 Lasioglossum ( Dialictus ) cactorum sp. nov. urn:lsid:zoobank.org:act: A034807A-0DCB-48D2-9C47-EA6271D76562 Figs 16–18 , 93C , 114A Diagnosis Females of Lasioglossum cactorum sp. nov. can be recognized by the unusual rims of T1–3, which are extremely narrow, abruptly depressed, and with long and dense lateral hair fringes, head broad (face length/width ratio ~0.83) and often quite large, mesepisternum rugose or with very dense punctures at least dorsally (i <1 pd), T1 without impunctate apicolateral oval patches, T2–4 with dark spiracular spots, and supraclypeal area sometimes black or golden-green medially. They are most similar to L . festinum sp. nov. and L . mesillense . Both of these species have the rims of T1–3 wide and flat and T1 with impunctate apicolateral oval patches. In addition, females of L . festinum sp. nov. have T2 lacking dark spiracular spots, and females of L . mesillense have the supraclypeal area always metallic blue-green. Males of L . cactorum sp. nov. can be recognized by T1–4 strongly convex in lateral view, with very narrow, steeply depressed rims and no change in punctation or sculpture across the premarginal line, mesepisternum densely punctate (i <1 pd), propodeum dorsolateral slope smooth and distinctly punctate, face below eye emargination covered in dense tomentum, and metasoma entirely black. They are most similar to L . arenisaltans sp. nov. , L . clematisellum , and L . minckleyi sp. nov. All of these species have the metasomal terga mostly flat in lateral view with sparser, less distinct punctures across the premarginal line. In addition, males of L . arenisaltans sp. nov. have the propodeum dorsolateral slope rugulose and metasoma often red-orange. Males of L . clematisellum are smaller (about 4 mm ), with the mesepisternum more sparsely punctate dorsally (i=1–2 pd), and propodeum dorsolateral slope weakly rugulose. Males of L . minckleyi sp. nov. have the face slightly shorter (length/width ratio ~0.8) and metasoma often partially red-orange. Etymology The specific epithet ‘ cactorum ’ is the Latin genitive plural of the noun ‘ cactus ’. It refers to this species’ frequent association with flowering plants in the family Cactaceae . An appropriate translation would be the cactus sweat bee. Material examined Holotype UNITED STATES Nevada ; Clark Co. , 2.2 mi. SSW of Mormon Well ; 36.6147° N , 115.1111° W ; 2008 m a.s.l. ; 14 Jun. 2004 ; E. Ahlstrom and D. Skandilis leg.; PCYU . [Verbatim label: USA NV Clark Co. 2.2 mi. SSW Mormon Well 6588ft 11S E668922 N4053788 14Jun 2004 PnTrp, fl ylw, E. Ahlstrom, D. Skandilis / BBSL537603 // 2374F06 // HOLOTYPE / Lasioglossum ( Dialictus ) cactorum Gardner and Gibbs ] Paratypes UNITED STATES Arizona 1 ♀ ; Maricopa Co. , Mountain View Park ; 33.5787° N , 112.0799° W ; 18 May 2017 ; S.J. Hall et al . leg.; ASUHIC 2 ♀♀ ; Grand Canyon Mile 1792; [ 36° N , 112° W ]; 11 Jun. 1953 ; G.D. Butler leg.; UAIC 1 ♀ ; same collection data as for preceding; USNM 1 ♀ ; Grand Canyon Mile 32; [ 36° N , 112° W ]; 6 Jun. 1953 ; G.D. Butler leg.; UAIC 1 ♀ ; Mojave Co. , White Hills , Lk. Mead NRA ; [ 35.83° N , 114.32° W ]; 488 m a.s.l. ; 30 Mar. 1993 ; T. Griswold and V. Tepedino leg.; ex Arctomecon californica ; BBSL . – California 1 ♀ ; Inyo Co. , 1 km SE of Swansea ; [ 36.52° N , 117.9° W ]; 19 Sep. 1993 ; T. Griswold leg.; BBSL 1 ♀ ; San Bernardino Co. , 9 air mi. S of Baker , Zzyzx Springs ; [ 35.14° N , 116.1° W ]; 20–21 Apr. 1977 ; M. Buegler leg.; EMEC 1 ♀ ; same location as for preceding; 22 Apr. 1977 ; Chemsak leg.; EMEC 1 ♀ ; Anza Borrego , Vallecito Crk. ; 32.9157° N , 116.2255° W ; 8 Jun. 2013 ; K.E. Borchers leg.; ex Psorothamnus spinosus ; WRME 2 ♀♀ ; San Diego Co. , Borrego Springs (NW side), YPT, rocky draw nr base of Indian head; 33.2925° N , 116.4° W ; 213 m a.s.l. ; 12 Jan. 2011 ; John / Derrin Pinto leg.; UCRC 2 ♀♀ ; Riverside Co. , Corn Spring , Chuckwalla Mts , 7.5 mi. SE of Desert Center ; [ 33.626° N , 115.325° W ]; 488 m a.s.l. ; 15–17 Jun. 1973 ; J.P. and K.E. Donahue leg.; LACM 1 ♀ ; San Bernardino Co. , Cove Spr. , Granite Mts ; [ 34.78° N , 115.65° W ]; 1311 m a.s.l. ; 31 May 1981 ; T. Griswold leg.; BBSL 1 ♀ ; Death Valley ; [ 36.5° N , 116.9° W ]; 26 Jun. 1953 ; G.D. Butler leg.; ex Stanleya ; UAIC 1 ♀ ; Death Valley National Monument ; [ 36.5° N , 116.9° W ]; 31 Mar. 1976 ; M.A. Ivie leg.; MTEC 1 ♀ ; Inyo Co. , Death Valley NP , E of Travertine Spr. ; 36.4388° N , 116.8258° W ; 16 Mar. 1998 ; T. Griswold leg.; BBSL 2 ♀♀ ; Riverside Co. , Deep Canyon ; 33.6475° N , 116.3806° W ; 295 m a.s.l. ; 17 Apr. 2009 ; ex cactus; UCRC 1 ♂ ; Riverside Co. , Deep Canyon ; [ 33.62° N , 116.4° W ]; 11 Jul. 1963 ; E.I. Schlinger leg.; UCRC 1 ♂ ; same location as for preceding; 13 Jun. 1963 ; E.I. Schlinger leg.; ex Eriogonum ; UCRC 1 ♀ ; same location as for preceding; 11 Nov. 1963 ; M.E. Irwin leg.; UCRC 1 ♀ ; Inyo Co. , DVNM Keane Spr. ; [ 36.745° N , 116.902° W ]; 18 Apr. 1994 ; W.R. Bowlin leg.; ex Arctomecon merriamii ; BBSL 1 ♀ ; Inyo Co. , DVNM Klare Spr. ; [ 36.841° N , 117.091° W ]; 15 Apr. 1994 ; W.R. Bowlin leg.; ex Argemone spp.; BBSL 2 ♀♀ ; Inyo Co. , DVNM Mes. Spr. ; [ 36.964° N , 117.368° W ]; 13 Apr. 1994 ; W.R. Bowlin leg.; ex Arctomecon merriamii ; BBSL 1 ♀ ; Inyo Co. , DVNM, Lost Burro Gap , Cottonwood Mts ; [ 36.746° N , 117.52° W ]; 914 m a.s.l. ; 15 Oct. 1985 ; R.R. Snelling leg.; ex Ericameria nauseosa var. nauseosa ; LACM 1 ♀ ; Inyo Co. , Emigrant Pass , E of Tecopa ; [ 35.89° N , 116.08° W ]; 15 Sep. 1993 ; T. Griswold leg.; ex Eriogonum deflexum ; BBSL 2 ♀♀ ; Inyo Co. , Grapevine Canyon , Death Valley N. M. ; [ 37.005° N , 117.356° W ]; 760 m a.s.l. ; 16 Sep. 1993 ; T. Griswold leg.; ex Cleomella obtusifolia ; BBSL 1 ♀ ; San Bernardino Co. , Mid Hills , SSE of Cima ; [ 35.15° N , 115.43° W ]; 14 Sep. 1975 ; T. Griswold leg.; BBSL 1 ♀ ; San Bernardino Co. , Norris Camp ; 34.8089° N , 115.6281° W ; 1215 m a.s.l. ; 13 May 2013 ; D. Yanega leg.; UCRC 2 ♀♀ ; Riverside Co. , Palm Springs ; 33.6796° N , 116.548° W ; 6–12 May 2014 ; F.D. Parker and T.D. McIntyre leg.; BBSL 1 ♀ ; same location as for preceding; 13–16 May 2014 ; F.D. Parker and T.D. McIntyre leg.; BBSL 2 ♀♀ ; same location as for preceding; 14–18 Apr. 2014 ; F.D. Parker and T.D. McIntyre leg.; BBSL 7 ♀♀ ; same location as for preceding; 28 Apr. 2014 ; F.D. Parker and T.D. McIntyre leg.; BBSL 1 ♀ ; Sunset Cove , Granites Res. Stn. Mojave Desert ; 34.77903° N , 115.66311° W ; 24 Apr. 2018 ; J. Braun leg.; PCYU 1 ♀ ; same location as for preceding; 4 May 2018 ; J. Braun leg.; PCYU 1 ♀ ; Inyo Co. , Surprise Canyon ; [ 36.11° N , 117.15° W ]; 29 Apr. 1953 ; R.O. Schuster leg.; EMEC 1 ♀ ; same location as for preceding; 6 May 1961 ; D.Q. Cavagnaro leg.; UCDC 2 ♀♀ ; Inyo Co. , Surprise Canyon , Panamint Mountains ; [ 36.11° N , 117.15° W ]; 24 Apr. 1957 ; P.D. Hurd leg.; ex Eriogonum inflatum ; EMEC 1 ♀ ; San Bernardino Co. , Willow Wash , Sec24 T13N R10E ; [ 35.2° N , 115.87° W ]; 10 May 1982 ; T. Griswold leg.; BBSL 2 ♀♀ ; Riverside Co. , Windy Point ; 33.892° N , 116.6393° W ; 24 Mar. 2019 ; J. Gardner leg.; ex Ferocactus cylindraceus ; WRME 1 ♀ ; San Bernardino Co. , Zzyzx Springs ; [ 35.14° N , 116.1° W ]; 26 Mar. 1988 ; S. O’Keefe leg.; EMEC 10 ♀♀ ; San Bernardino Co. ; 34.8681° N , 115.7731° W ; 16–17 Aug. 2011 ; N. Darby leg.; WRME 1 ♀ ; San Bernardino Co. ; 34.8794° N , 115.7808° W ; 16–17 Aug. 2011 ; N. Darby leg.; WRME . – Nevada 2 ♀♀ ; Clark Co. , 0.2 mi. W of Hiko Spr. ; 35.1675° N , 114.6813° W ; 609 m a.s.l. ; 27 Apr. 2004 ; S. Higbee and E. Ahlstrom leg.; BBSL 1 ♀ ; Clark Co. , 0.5 mi. SW of Cabin Spr. ; 36.5362° N , 114.0844° W ; 1368 m a.s.l. ; 17 Aug. 2004 ; E. Ahlstrom leg.; ex Eriogonum deflexum ; BBSL 1 ♀ ; Clark Co. , 2 mi. E of Sawmill Canyon ; 36.7008° N , 115.0492° W ; 1439 m a.s.l. ; 2 Sep. 2004 ; E. Rentz leg.; ex Eriogonum fasciculatum ; BBSL 1 ♀ ; Clark Co. , 2.1 mi. N of Harris Spr. ; 36.2707° N , 115.5434° W ; 1775 m a.s.l. ; 22 Jun. 2004 ; L. Saul leg.; ex Argemone munita ; BBSL 4 ♀♀ ; same collection data as for holotype; BBSL 1 ♀ ; Clark Co. , 2.7 mi. ESE of Red Bluff Spr .; 36.6209° N , 114.2066° W ; 15 Apr. 2005 ; S. Higbee leg.; PCYU 2 ♀♀ ; Clark Co. , 3.5 mi. SE of Hiko Spr .; 35.1252° N , 114.6432° W ; 235 m a.s.l. ; 27 Apr. 2004 ; S. Higbee and E. Ahlstrom leg.; BBSL 1 ♀ ; 4 mi. E. of Glendale ; [ 36.66° N , 114.49° W ]; 20 Jun. 1939 ; Timberlake leg.; ex Sphaeralcea ; UCRC 1 ♀ ; Nye Co. , Ash Meadows ; [ 36.4° N , 116.3° W ]; 18 Apr. 1993 ; T. Griswold leg.; BBSL 1 ♀ ; Clark Co. , Columbia Pass ; 35.8224° N , 115.4835° W ; 1319 m a.s.l. ; 31 Aug. 2004 ; S. Higbee leg.; ex Eriogonum deflexum ; BBSL 1 ♀ ; Clark Co. , E of Trapp Ridge ; 36.3905° N , 114.1287° W ; 4 Aug. 1998 ; M. Andres and C. Shultz leg.; BBSL 4 ♀♀ ; Clark Co. , Gypsum Spring ; 36.2093° N , 114.912° W ; 12 Mar. 1998 ; T. Griswold leg.; BBSL 1 ♀ ; Clark Co. , Gypsum Wash ; 36.2177° N , 114.8965° W ; 12 Mar. 1998 ; T. Griswold leg.; BBSL 1 ♀ ; Clark Co. , 22 mi. S of Las Vegas ; [ 35.85° N , 115.25° W ]; 3 Apr. 1953 ; J.W. MacSwain leg.; EMEC 5 ♀♀ ; Clark Co. , Lee Canyon ; 36.4476° N , 115.5097° W ; 1252 m a.s.l. ; 7 Sep. 2004 ; S. Higbee and T. Griswold leg.; BBSL 3 ♀♀ ; same location as for preceding; 7 Sep. 2004 ; S. Higbee and T. Griswold leg.; PCYU 1 ♀ ; Clark Co. , Mormon Well ; 36.6752° N , 115.0952° W ; 1 Jul. 1998 ; M. Andres and C. Shultz leg.; BBSL 2 ♀♀ ; Clark Co. , Peek a Boo Canyon ; 36.5065° N , 115.1477° W ; 16 Jul. 1998 ; M. Andres and C. Shultz leg.; BBSL 1 ♀ ; Clark Co. , Pulsipher Wash ; 36.8073° N , 114.1143° W ; 16 Sep. 1998 ; W. Bowlin leg.; BBSL 1 ♀ ; Clark Co. , Sandy Valley ; 35.852° N , 115.6715° W ; 25 Aug. 1998 ; O. Messinger and C. Shultz leg.; BBSL 1 ♀ ; Clark Co. , Sheep Mountain ; 35.7598° N , 115.3213° W ; 11 Aug. 1998 ; M. Andres , C. Shultz and T. Griswold leg.; BBSL 1 ♀ ; Clark Co. , Sheep Range ; 36.4382° N , 115.2983° W ; 28 May 1998 ; F.D. Parker leg.; BBSL 6 ♀♀ ; Clark Co. , Wheeler Wash ; 36.239° N , 115.8865° W ; 20 Jul. 1998 ; M. Andres and C. Shultz leg.; BBSL . – Utah 1 ♀ ; Washington Co. , summit, road to Lytle Ranch Preserve ; [ 37.14° N , 114.04° W ]; 20 Aug.–9 Sep. 1987 ; W.J. Hanson and M. T. leg.; BBSL . Description Female COLOURATION. Head and mesosoma blue to blue-green; clypeus apical colour orange, reddish brown, or nearly black; labrum orange; mandible orange with black basal spot or band and red tip; flagellum reddish brown dorsally, orange ventrally; pronotal lobe orange, reddish brown, or nearly black; metasoma red to orange with dark spiracular spots on T2–4, sometimes dark on discs of T4–5; legs reddish brown with femur-tibia joints and tarsi mostly orange; tegula orange; wing membrane hyaline, veins with subcosta dark brown, stigma pale amber, otherwise pale amber to brown. PUBESCENCE. Body hair colour white. Tomentum dense on paraocular area, frons, gena, pronotal collar and lobe, space between pronotal lobe and tegula, and metanotum anteromedially; sparse on preëpisternum, mesepisternum anteroventrally, metepisternum, T2–3 laterally, and T4 throughout. Scutum hair thin to moderately plumose. Wing hairs dark or light, short and dense. Acarinarial fan complete or incomplete, very sparse. T2–3 fringes very long and dense laterally, absent medially. SURFACE SCULPTURE. Clypeus punctures irregularly sparse (i <2 pd), slightly larger and sparser in apcial half, sculpture shiny; supraclypeal area punctures dense (i ≤ 1 pd), slightly sparser medially (i=1–2 pd), sculpture shiny; paraocular area punctures dense (i <1 pd), sometimes becoming moderately sparse around antenna socket (i=1–2 pd), sculpture shiny; frons punctures dense (i <1 pd), sculpture shiny; vertex punctures minute, sparse (i=1–3pd), obscure medially, sculpture shiny;gena punctures moderately dense (i =1–2 pd), sculpture shiny; postgena sculpture weakly ruguloso-lineate to imbricate; tegula punctures absent; scutum punctures dense (i ≤ 1 pd), becoming sparse submedially and anteromedially (i =1–3 pd), sculpture shiny, becoming tessellate anteromedially; scutellum punctures dense marginally and on median line (i ≤ 1 pd), moderately sparse submedially (i=1–2 pd), diversopunctate, sculpture shiny; metanotum sculpture shiny and minutely reticulate-punctate medially, becoming finely rugulose laterally; metapostnotum rugae weak, anastomosing, not reaching margin, sculpture shiny on posterior margin, otherwise tessellate; preëpisternum sculpture reticulate-punctate; hypoepimeron punctures crowded (i=0 pd), sculpture ruguloso-punctate; mesepisternum punctures crowded (i=0 pd), becoming slightly sparser ventrally (i ≤ 1 pd), sculpture shiny, sometimes becoming areolate-rugulose dorsally; metepisternum sculpture lineate dorsally, rugulose medially, imbricate ventrally; propodeum lateral face sculpture tessellate; propodeum posterior face sculpture tessellate and sparsely punctate (i = 1–6 pd), becoming shiny medially; T1 anterior face sculpture shiny; T1 dorsal surface punctures fine, moderately sparse (i =1–3 pd), becoming sparser apicolaterally (i =2–6 pd), sculpture shiny; T2 disc punctures fine, sparse (i=1–3 pd), disc sculpture shiny, rim punctures fine, sparse (i =1–3 pd), rim sculpture shiny. STRUCTURE. Face length/width ratio 0.83 (± 0.02 SD). Clypeus projecting ~50% below suborbital tangent; clypeal area length/width ratio 0.37 (± 0.03 SD); apicolateral denticles rounded obtuse points; supraclypeal area length/width ratio 0.75 (± 0.03 SD). Forewing with 3 submarginal cells; pronotal angle obtuse; tegula shape normal. Intertegular distance 0.98 (± 0.07 SD) mm. Scutum length/width ratio 0.86 (± 0.03 SD); scutum/scutellum length ratio 2.92 (± 0.16 SD); scutellum/metanotum length ratio 1.52 (± 0.13 SD); metanotum/metapostnotum length ratio 0.8 (± 0.07 SD). Propodeum lateral carinae not reaching dorsal margin; oblique carina very weak or absent. T2 depressed apical rim linear. (n= 10) Male COLOURATION. Head and mesosoma blue to blue-green; clypeus apical colour reddish brown to orange; labrum orange; mandible orange with black basal band and red tip; flagellum reddish brown, sometimes orange ventrally; pronotal lobe reddish brown to orange; metasoma black to reddish brown with downcurved lateral areas of terga becoming orange to translucent yellow; legs reddish brown with femur-tibia joints, base and apex of tibiae, and tarsi orange; tegula orange; wing membrane hyaline, veins brown to dark brown. PUBESCENCE. Body hair colour white. Tomentum dense on face below eye emargination, gena, pronotal angle and lobe, and space between pronotal lobe and tegula; sparse on episterna. Scutum hair thin to Fig. 16. Lasioglossum ( D. ) cactorum sp. nov. , ♀. A . Dorsal habitus. B . Lateral habitus. C . Face. D . Propodeum. E . Metasoma. Scale bars: 1 mm. Fig. 17. Lasioglossum ( D. ) cactorum sp. nov. , ♂. A . Dorsal habitus. B . Lateral habitus. C . Face. D . Propodeum and metasoma. Scale bars: 1 mm. moderately plumose. Sterna hair short (1–1.5 OD), densely plumose, dense and erect. Wing hairs dark or light, short and sparse. SURFACE SCULPTURE. Clypeus punctures dense (i ≤ 1 pd), sculpture shiny; supraclypeal area punctures dense (i <1 pd), sculpture shiny; paraocular area punctures dense (i <1 pd), sculpture shiny; frons punctures dense (i <1 pd), sculpture shiny; vertex punctures moderately dense (i=1–2 pd), sculpture shiny; gena punctures moderately dense (i=1–2 pd), sculpture shiny; postgena sculpture lineate, sometimes becoming shiny anteriorly; tegula punctures absent; scutum punctures sparse (i=1–3 pd), becoming dense marginally (i ≤ 1 pd), sculpture shiny; scutellum punctures sparse (i=1–3 pd), becoming dense marginally (i ≤ 1 pd), sculpture shiny; metanotum sculpture shiny and densely punctate (i ≤ 1 pd), becoming rugulose laterally; metapostnotum rugae strong, anastomosing, not reaching margin, sculpture shiny to weakly tessellate; preëpisternum sculpture areolate; hypoepimeron punctures crowded (i =0 pd), sculpture areolate; mesepisternum punctures dense (i <1 pd) to crowded (i =0 pd), sculpture shiny; metepisternum sculpture lineate dorsally, weakly rugulose ventrally; propodeum lateral face punctures dense (i ≤ 1 pd), sculpture tessellate, becoming shiny posteriorly; propodeum posterior face sculpture shiny and densely punctate (i ≤ 1 pd), becoming sparse to absent medially; T1 anterior face sculpture shiny; T1 dorsal surface punctures moderately sparse (i= 1–3 pd), sculpture shiny; T2 disc punctures moderately dense (i=1–2 pd), disc sculpture shiny, rim punctures moderately sparse (i= 1–3 pd), rim sculpture shiny. STRUCTURE. Face length/width ratio 0.85 (± 0.02 SD). F1:pedicel length ratio 1.01 (± 0.18 SD); F2:F1 length ratio 1.85 (± 0.03 SD); F2 length/width ratio 1.68 (± 0.05 SD); F9 length/width ratio 1.18 (± 0.01 SD). Forewing with 3 submarginal cells; pronotal angle obtuse; tegula shape normal. Intertegular distance 0.88 (± 0.11 SD) mm. Scutum length/width ratio 0.93 (± 0.01 SD); scutum/scutellum length ratio 2.65 (± 0.02 SD); scutellum/metanotum length ratio 1.8 (± 0.1 SD); metanotum/metapostnotum length ratio 0.62 (± 0.03 SD). Propodeum lateral carinae not reaching dorsal margin; oblique carina absent. Metasomal terga strongly convex. (n =2) GENITALIA. Not examined. Range Mojave and Sonoran Deserts of southern Nevada and California , southwestern Utah , and Arizona ( Fig. 18 ). Floral records ASTERACEAE Giseke : Ericameria : E . nauseosa (Pall. ex Pursh)G.L.Nesom &Baird : E . n . var. nauseosa (Pall. ex Pursh) G.L. Nesom & Baird BRASSICACEAE Burnett : Stanleya Nutt. CACTACEAE Juss. Ferocactus Britton & Rose : F . cylindraceus (Engelm.) Orcutt CLEOMACEAE Bercht. & J. Presl : Cleomella DC. C . obtusifolia Torr. & Frém. FABACEAE Juss. Psorothamnus : P . spinosus (A.Gray) Barneby MALVACEAE Juss. Sphaeralcea A. St. -Hil. • PAPAVERACEAE Juss. Arctomecon Torr. & Frém. A . californicum Torr. & Frém. A . merriamii Coville Argemone L. A . munita Durand & Hilg. POLYGONACEAE Juss. Eriogonum Michx. E . deflexum Torr. E . fasciculatum Benth. E . inflatum Torr. DNA barcodes Six sequences available (BOLD process IDs: DLII909-07, DLII910-07, DLII1028-07, DLII1691-09, BHTT020-09, DLIII179-19; BIN: BOLD:AAE1189). Lasioglossum cactorum sp. nov. differs from all other western red-tailed L . ( Dialictus ) by 5 fixed substitutions: 213(C), 318(T), 379(A), 553(A), and 573(C) (Supplementary file 4). Fig. 18. Georeferenced collection records of Lasioglossum ( D. ) cactorum sp. nov. (black squares) and predicted distribution by maximum entropy ecological niche modeling in Maxent (colour shading). Warmer colours indicate higher cloglog probability of occurrence. Remarks Although Lasioglossum cactorum sp. nov. has been frequently collected from cactus flowers, it is not oligolectic on them. There is considerable variation in the size of this species, especially of the head, and in the sculpturing of the mesepisternum. This variation, combined with the year-round phenology of this species and phylogenetic data, suggests it is likely social. An undescribed species from the Chihuahuan Desert has similarly narrow and strongly depressed rims of T1–3, but the metasoma is all black. DNA barcodes and other morphological features also distinguish these two species.