Lasioglossum (Dialictus) diabolicum, Gardner & Gibbs, 2023

Gardner, Joel & Gibbs, Jason, 2023, Revision of the Nearctic species of the Lasioglossum (Dialictus) gemmatum species complex (Hymenoptera: Halictidae), European Journal of Taxonomy 858 (1), pp. 1-222 : 52-60

Lasioglossum (Dialictus) diabolicum sp. nov.

urn:lsid:zoobank.org:act:2E554E7E-C8BF-49C4-AC08-2EB5886A18E3

Figs 15–17 , 76D , 87B , 97B , 98A , 99B , 100A , 117B , 119B , 120B

Diagnosis

Females of L. diabolicum sp. nov. have the tegula relatively small (barely reaching posterior margin of mesoscutum in dorsal view if at all), inner posterior margin straight, with a blunt posterior angle or small bump, and mediolateral area usually somewhat sparsely punctate (IS ≥1 PD); mesepisternum punctures usually larger and slightly sparser than hypoepimeron punctures; mesoscutum and mesepisternum sometimes shiny; metapostnotum usually dull with anastomosing rugae; mesoscutum with dense erect pubescence (each seta less than its length from the next nearest one with intervening setae short but having measurable length up to 0.5 OD); and tegula and metasoma often red-orange.

Females of L. diabolicum sp. nov. are most similar to those of L. deludens sp. nov., L. ellisiae , and L. perparvum . Females of L. deludens have the tegula impunctate medially, mesoscutum punctures finer in comparison to mesepisternum, and metasoma black to brown. Females of L. ellisiae have the mesepisternum punctures as fine and dense as on hypoepimeron, tegula slightly larger (reaching posterior margin of mesoscutum in dorsal view) with inner posterior margin sinuous, and metapostnotum usually shiny with subparallel rugae. In red-tailed forms, L. diabolicum usually have the basal half of T1 dark brown, while in L. ellisiae it is entirely red. Females of L. perparvum have the mesoscutum with much shorter, sparser pubescence (each long erect seta about its length from the next nearest one, with intervening setae no more than stubble), mesoscutum and mesepisternum dull, and metasoma dark brown to black.

Males of L. diabolicum sp. nov. have the tegula relatively small (as in the female); mesoscutum usually shiny and coarsely and moderately sparsely punctate (IS = 1–2 PD); mesepisternum usually densely punctate (IS ≤ 1 PD); T1–T2 with discs finely and moderately sparsely punctate (IS = 1–2 PD) and apical rims impunctate; and mesoscutum with numerous long plumose setae (as in the female).

Males of L. diabolicum sp. nov. are most similar to those of L. ellisiae , L. helianthi , and L. perparvum . Males of L. ellisiae have the mesoscutum more evenly and densely punctate (IS ≤1 PD between parapsidal lines) and disc of T2 sometimes more deeply and densely punctate in basal half (IS ≤1 PD). Males of L. helianthi have the mesoscutum entirely densely punctate (IS ≤ 1 PD) and T1–T2 more deeply and densely punctate (IS ≤ 1 PD) including apical rims in part. Males of L. perparvum have the mesoscutum usually tessellate, more finely and densely punctate (IS ≤1 PD), and with sparse erect setae (with gaps 0.5 OD or more visible in lateral view) appearing simple at 40 × magnification.

Some other species in the L. stictaspis species complex can also be very similar in both sexes, but have the tegula slightly larger (reaching or exceeding posterior margin of mesoscutum in dorsal view) and inner posterior margin concave with a distinct, rounded posterior projection.

Etymology

The specific epithet ʻ diabolicum ʼ is a Latin adjective meaning ʻdevilishʼ. It is a reference to this species’ close relationship to L. angelicum sp. nov. and its variable morphology and DNA barcodes which make delimitation and identification very difficult.

Material examined

Holotype UNITED STATES – Utah • ♀; Garfield Co., The Gulch ; 37.8494° N, 111.313° W; 14 Aug. 2001; S. Messinger leg.; ex Melilotus officinalis subsp. alba ; BBSL409921 .

[Verbatim label: USA UT Garfield Co. / The Gulch, 12S E4772461 N4189153 // Melilotus alba // 14 August 2001 / S. Messinger // NativeBeeSurvey / USDA,Logan, Utah / BBSL 409921 // BOLD / BHTT 023-09 / B03750811- UT // HOLOTYPE / Lasioglossum (Dialictus) diabolicum Gardner and Gibbs ]

Paratypes

UNITED STATES – Arizona • 1 ♀; Yuma ; [32.69° N, 114.63° W]; 26 Jun. 1951; L.A. Carruth leg.; UAIC • 1 ♀; ibid.; Jun. 1954; J. Ellington leg.; NMSU • 1 ♀; ibid.; 13 Apr. 1955; G.D. Butler, F.G. Werner leg.; ex Pluchea ; UAIC • 1 ♀; ibid.; 4 Jun. 1955; G.D. Butler leg.; ex Solanum “ elaegnif -”; UAIC. – California • 2 ♂♂; Imperial Co., Algodones Dunes, Roadrunner Campground ; 32.9° N, 115.1167° W; elev. 66 m; 11–15 Nov. 2007; R.B. Kimsey, L. Kimsey, T.J. Zavortink leg.; UCDC • 1 ♀; Needles ; [34.85° N, 114.61° W]; “II. III 1922 ”; J.A. Kusche leg.; CAS CASENT 8416761 . – Colorado • 2 ♀♀; Mesa Co., 1.34 mi. ESE of Clifton ; 39.0832° N, 108.4269° W; 6 Aug. 2015; S.J. Burrows leg.; BBSL983351 , BBSL983354 • 1 ♀; Mesa Co., Colorado National Monument , 0.5 mi. inside E entrance; [39.03° N, 108.63° W]; elev. 1524 m; 6 May 1987; U.N. Lanham, M.S. Weissman leg.; ex Lepidium ; UCMC. – Nevada • 1 ♀; Clark Co., 8 mi. S of Overton ; [36.42° N, 114.45° W]; 27 Apr. 1972; George E. Bohart, F.D. Parker, P.F. Torchio leg.; ex Sphaeralcea ; BBSL510025 • 1 ♀; Clark Co., Las Vegas Valley Water District ; 36.1756° N, 115.1904° W; elev. 651 m; 10 Jun. 2004; S. Higbee, L. Saul leg.; BBSL537650 • 3 ♀♀; Clark Co., Mesquite ; [36.81° N, 114.07° W]; 13 Aug. 1951; E.L. Kessel leg.; CAS • 2 ♀♀; Clark Co., Spring Mountain Ranch ; [36.07° N, 115.45° W]; May–Jul. 1988; M.J. Verchick leg.; BBSL700770 , BBSL700773 • 2 ♀♀; Las Vegas, 8930 Lansberry Court ; 36.1072° N, 115.2863° W; elev. 780 m; 1–20 Jul. 2014; K. Ribardo leg.; UCRC ENT 480495 , 480579 . – Utah • 1 ♀; Emery Co., Bell Canyon, San Rafael Reef ; [38.589° N, 110.808° W]; elev. 1524 m; 26 Jul. 1983; F.D. Parker, A. Parker, Terry L. Griswold leg.; BBSL FaunalSurvey No. 000039439 • 1 ♂; ibid.; 26 Jul. 1983; F.D. Parker, A. Parker, Terry L. Griswold leg.; BBSL FaunalSurvey No. 000039446 • 2 ♀♀, 1 ♂; ibid.; 26 Jul. 1983; F.D. Parker, A. Parker, Terry L. Griswold leg.; CUIC • 1 ♀; Emery Co., Buckskin Spring, north of Goblin Valley ; [38.62° N, 110.67° W]; elev. 1554 m; 21 Apr. 1986; Terry L. Griswold leg.; BBSL FaunalSurvey No. 000130265 • 2 ♀♀; Emery Co., Buckskin Spring, north of Goblin Valley ; [38.62° N, 110.67° W]; elev. 1570 m; 28 Jul. 1981; F.D. Parker, Terry L. Griswold, D.F. Veirs leg.; BBSL FaunalSurvey No. 000039440, FaunalSurvey No. 000039441 • 1 ♀; Emery Co., Castle Dale; [39.21° N, 111.02° W]; 10 Aug. 1957; Charles D. Michener leg.; ex Cleome serrulata ; SEMC • 3 ♀♀; Emery Co., Wild Horse Creek north of Goblin Valley ; [38.57° N, 110.82° W]; elev. 1494 m; 21–23 Jul. 1981; D.F. Veirs, F.D. Parker, Terry L. Griswold leg.; BBSL FaunalSurvey No. 000039442, FaunalSurvey No. 000039443, FaunalSurvey No. 000039444 • 2 ♀♀; ibid.; 21–23 Jul. 1981; D.F. Veirs, F.D. Parker, Terry L. Griswold leg.; CUIC • 1 ♀; ibid.; 25–28 Jul. 1983; Parkers, Terry L. Griswold leg.; BBSL FaunalSurvey No. 000039445 • 2 ♂♂; ibid.; 25–28 Jul. 1983; Parkers, Terry L. Griswold leg.; CUIC • 1 ♀; Garfield Co., 2.3 mi. S of Hot Canyon ; 37.8506° N, 111.3551° W; 19 May 2003; B. Hanson leg.; BBSL516270 • 1 ♀; Garfield Co., Calf Creek ; [37.8° N, 111.41° W]; 29 Aug. 1985; F.D. Parker leg.; BBSL700742 • 1 ♀; Garfield Co., Capitol Reef National Park, Sulfur Creek ; [38.3° N, 111.3° W]; 26 Jul. 1978; Lindahl leg.; BBSL700743 • 1 ♀; Garfield Co., Escalante River, 1.3 mi. W of Death Hollow junction; 37.7787° N, 111.5326° W; 13 May 2002; J. Richmond leg.; ex Melilotus officinalis ; BBSL437534 • 1 ♀; Garfield Co., Escalante River, 1.3 mi. W of Death Hollow junction; 37.7808° N, 111.5353° W; 13 May 2001; C. Davidson leg.; ex Tamarix sp. ; BBSL438836 • 1 ♀; ibid.; 24 Aug. 2001; C. Davidson leg.; ex Melilotus alba ; BBSL419411 • 1 ♀; ibid.; 15 Jul. 2002; O.I. Messinge leg.; ex Tamarix sp. ; BBSL451103 • 1 ♀; Garfield Co., Shootering Canyon; [37.76° N, 110.7° W]; 28 Jul. 1979; Debby Vogt leg.; BBSL700741 • 1 ♀; Grand Co., 3 mi. E of Bartlett Flat ; [38.64° N, 109.78° W]; elev. 1524 m; 5 May 1989; Terry L. Griswold leg.; BBSL FaunalSurvey No. 000130266 • 1 ♂; Grand Co., Moab Highway 128 , 2 mile marker roadside; [38.6117° N, 109.5513° W]; 15 Aug. 1992; Laurence Packer leg.; PCYU • 1 ♀; Kane Co., 0.22 mi. N of Mudhole Spring ; 37.346° N, 111.2135° W; 6 Aug. 2001; K. Moredock leg.; ex Sphaeralcea sp. ; BBSL410597 • 1 ♀; Kane Co., 0.72 mi. NE of Sunset Natural Arch ; 37.3822° N, 111.0374° W; 25 Apr. 2001; Terry L. Griswold leg.; ex Streptanthella longirostris ; BBSL409348 • 1 ♀; Kane Co., 2 mi. NNW of Duffy Mesa ; 37.8507° N, 111.3544° W; 10 May 2001; C. Davidson leg.; ex Salix exigua ; BBSL401313 • 1 ♂; Kane Co., Paradise Canyon; 37.4048° N, 111.6497° W; 18 Aug. 2003; Terry L. Griswold leg.; ex Chrysothamnus greenei ; BBSL488442 • 1 ♀; Millard Co., Oak Creek Canyon; [39.35° N, 112.26° W]; 27 May 1958; G.F. Knowlton leg.; ex Salix sp. ; SEMC • 1 ♀; San Juan Co., Canyonlands, Box hanging garden ; [38.2° N, 109.9° W]; 11 Jul. 1993; J.F. Fowler leg.; BBSL700706 • 2 ♀♀; San Juan Co., Glen Canyon, Camp hanging garden ; [37.1° N, 110.9° W]; 26 Jun. 1992; J.F. Fowler leg.; BBSL700843 , BBSL700853 • 1 ♀; ibid.; 26 Jun. 1992; J.F. Fowler leg.; CUIC • 1 ♂; San Juan Co., Glen Canyon, Hardwood hanging garden ; [37.1° N, 110.9° W]; 27 Jul. 1991; J.F. Fowler leg.; ex Thelypodium integrifolium ; BBSL700845 • 1 ♀; ibid.; 31 Jul. 1991; J.F. Fowler leg.; BBSL700849 • 1 ♀; San Juan Co., Glen Canyon, Hook hanging garden ; [37.1° N, 110.9° W]; 11 Jun. 1992; J.F. Fowler leg.; ex Cirsium rydbergii ; BBSL700847 • 1 ♀; San Juan Co., Glen Canyon , Iceberg Canyon ; [37.31° N, 110.74° W]; 16 May 1992; J.F. Fowler leg.; CUIC • 4 ♀♀; San Juan Co., Glen Canyon , Pyro hanging garden ; [37.1° N, 110.9° W]; 26 Jun. 1992; J.F. Fowler leg.; BBSL700848 , BBSL700851 , BBSL700852 , BBSL700854 • 1 ♀; Washington Co., 0.24 mi. SSW of Angels Landing; 37.266° N, 112.9487° W; 15 May 2006; B. Hays leg.; ex Tamarix sp. ; BBSL ZION25451 • 1 ♂; Washington Co., 5 mi. Leeds Canyon ; [37.31° N, 113.43° W]; 8 Jun. 1964; G.F. Knowlton leg.; SEMC • 1 ♀; Washington Co., Beaver Dam Wash ; [37.1° N, 114.02° W]; 10–24 Jun. 1987; BBSL700661 • 2 ♂♂; ibid.; 10–24 Jun. 1987; BBSL700819 , BBSL700825 • 1 ♀; ibid.; 10–24 Jun. 1987; WRME BBSL700669 • 2 ♂♂; ibid.; 10–24 Jun. 1987; WRME BBSL700821 , BBSL700832 • 2 ♀♀; Washington Co., Hurricane ; [37.17° N, 113.29° W]; 29 Apr. 1964; G.F. Knowlton leg.; SEMC • 1 ♂; Washington Co., Leeds ; [37.24° N, 113.36° W]; 19 Jul. 1963; G.F. Knowlton leg.; BBSL700841 • 1 ♀; ibid.; 28 Apr. 1964; G.F. Knowlton leg.; ex mustard; SEMC • 1 ♀; Washington Co., Mouth E. Virgin River; [37.16° N, 113.016° W]; 8–17 Sep. 1982; C.R. Nelson leg.; BBSL700675 • 1 ♀; Washington Co., Oak Creek Canyon; 37.2113° N, 112.9961° W; 4 May 2006; O.I. Messinge, Terry L. Griswold leg.; BBSL ZION25804 • 2 ♀♀; ibid.; 15 May 2006; B. Hays leg.; ex Penstemon humilis ; BBSL ZION25478 , ZION25479 • 1 ♂; Washington Co., Shivwits Indian Reservation; [37.19° N, 113.73° W]; 16 Jun. 1978; Hanson, G.F. Knowlton leg.; BBSL700836 • 1 ♀; Washington Co., St. George ; [37.1° N, 113.57° W]; 28 Jun. 1945; G.F. Knowlton leg.; UMSP • 2 ♂♂; ibid.; 9 Jun. 1962; G.F. Knowlton leg.; BBSL700839 , BBSL700840 • 1 ♂; ibid.; 9 Jun. 1962; G.F. Knowlton leg.; WRME BBSL700649 • 1 ♀; ibid.; 8 Jun. 1968; G.F. Knowlton leg.; WRME BBSL700677 • 1 ♀; Washington Co., Zion National Park, Birch Creek ; [37.32° N, 112.88° W]; 28 Jul. 1965; W.J. Hanson leg.; BBSL700688 • 3 ♀♀; Washington Co., Zion National Park , slide area; [37.3° N, 113° W]; 19–31 Aug. 1982; C.R. Nelson leg.; BBSL700678 , BBSL700679 , BBSL700680 • 1 ♂; Washington Co., Zion , Snail hanging garden ; [37.3° N, 113° W]; 5 Aug. 1991; J.F. Fowler leg.; BBSL700844 • 1 ♀; Wayne Co., Capitol Reef National Park , Freemont River , south of Krueger Orchard ; 38.2886° N, 111.2373° W; 24 Jun. 2002; S. Messinger leg.; ex Melilotus officinalis ; BBSL440041 • 2 ♂♂; ibid.; 24 Jun. 2002; S. Messinger leg.; ex Melilotus officinalis ; BBSL440021 , BBSL440040 • 1 ♂; Green River ; [39° N, 110.16° W]; 14 Jun. 1945; G.F. Knowlton leg.; UMSP • 1 ♀; Sutherland ; [39.39° N, 112.64° W]; 6 May 1958; G.F. Knowlton leg.; SEMC • 1 ♀, 1 ♂; Zion National Park ; [37.3° N, 113° W]; 13 Aug. 1929; Paul W. Oman leg.; SEMC .

Other material excluded from paratypes

MEXICO – Sonora • 1 ♀; Municipio de Agua Prieta; 31.2776° N, 109.0013° W; 28 Apr. 2000; Robert L. Minckley leg.; RLM SBV000588 .

UNITED STATES – Arizona • 1 ♀; Apache Co., Canyon de Chelly National Monument ; [36.13° N, 109.47° W]; 10 Nov. 1968; UCDC • 3 ♀♀; Maricopa Co., Phoenix, Cotton Research Center ; [33.404° N, 111.988° W]; 20–21 Sep. 1979; G.D. Butler leg.; ex cotton; UAIC • 1 ♀; Pinal Co., 10 km W of Maricopa; [33.05° N, 112.15° W]; 23 Mar. 1990; Robert L. Minckley, R. Gyuro leg.; SEMC • 2 ♀♀; 3 mi. W of Palo Verde; [33.35° N, 112.73° W]; 21 Feb. 1961; J.C. Bequaert leg.; ex Dithyrea wislizeni ; UAIC • 1 ♀; Arlington ; [33.33° N, 112.76° W]; 9 Jun. 1955; G.D. Butler leg.; ex alfalfa; UAIC • 1 ♀; Cottonwood ; [34.74° N, 112.01° W]; 27 Jun. 1957; F.G. Werner, G.D. Butler leg.; ex alfalfa; UAIC • 1 ♀; Gillespie Dam, 5 mi. S of Arlington ; [33.25° N, 112.76° W]; 21 Feb. 1961; J.C. Bequaert leg.; ex Lycium fremontii ; UAIC. – Nevada • 2 ♀♀; Nye Co., Ash Meadows National Wildlife Refuge, alkali seep/ Devils Hole Road ; 36.4126° N, 116.284° W; elev. 701 m; 23 Apr. 2014; Casey M. Delphia leg.; MTEC • 1 ♀; Nye Co., Ash Meadows National Wildlife Refuge, Longstreet Spring ; 36.4675° N, 116.3263° W; 23 Apr. 2014; J.B. Runyon leg.; MTEC • 1 ♀; Nye Co., Ash Meadows National Wildlife Refuge , North Entrance ; 36.4883° N, 116.3429° W; 26 Mar. 2008; D.A. Tanner leg.; BBSL. – Utah • 1 ♂; Emery Co., 2 air mi. W of Little Gilson Butte ; [38.59° N, 110.64° W]; 15–17 Sep. 1980; F.D. Parker leg.; BBSL FaunalSurvey No. 000039448 • 1 ♀; Utah Co., Provo ; [40.23° N, 111.66° W]; 14 Aug. 1950; G.F. Knowlton leg.; BBSL700686 • 1 ♂; Washington Co., Zion National Park , slide area; [37.3° N, 113° W]; 19–31 Aug. 1982; C.R. Nelson leg.; BBSL700838 .

Description

Female

COLOURATION. Head and mesosoma olive green; clypeus apex black; labrum reddish brown; mandible orange with black base and red apex; flagellum dark brown dorsally, lighter brown ventrally. Pronotal lobe dark brown; legs brown; tegula brown; wing membrane lightly infuscated, veins with subcosta dark brown, otherwise light brown. Metasoma black to reddish brown with rims of terga and sterna narrowly translucent yellow.

PUBESCENCE. Body pile colour white to pale yellow. Tomentum dense on pronotal angle and lobe, space between pronotal lobe and tegula, and T2–T3 basolaterally; sparse on gena, metepisternum, and T4. Mesoscutum pubescence moderately to densely plumose. Wing setae dark, short and dense. Acarinarial fan complete, dense. T2 fringes sparse, T3 fringes dense.

SURFACE SCULPTURE. Clypeus shiny, with punctures dense in basal third (IS <1 PD), large and irregularly spaced apically (IS <2 PD); supraclypeal area shiny, with punctures dense (IS ≤ 1 PD); paraocular area weakly imbricate around antenna socket, otherwise shiny, with punctures crowded (IS = 0 PD), irregularly sparser around antenna socket (IS <2 PD); frons reticulate, with punctures crowded (IS = 0 PD); vertex shiny, with punctures crowded laterally (IS = 0 PD), moderately sparse and obscure medially (IS = 1–2 PD); gena shiny, becoming lineolate posteriorly and ventrally, with punctures fine, moderately dense (IS = 1–2 PD); postgena lineolate. Tegula punctures dense (IS <1 PD), becoming sparse medially (IS = 1–3 PD); mesoscutum tessellate, with punctures dense (IS <1 PD), becoming moderately sparse anteromedially (IS = 1–2 PD); scutellum shiny, with punctures dense (IS ≤ 1 PD); metapostnotum finely reticulate, with rugae strong, anastomosing, reaching posterior margin; preëpisternum ruguloso-punctate; hypoepimeron shiny, with punctures crowded (IS = 0 PD); mesepisternum imbricate, with punctures dense (IS <1 PD); metepisternum finely rugulose; propodeum lateral surface tessellate, posterior surface tessellate. T1 anterior slope coriarious, disc shiny, with punctures fine, moderately sparse (IS = 1–3 PD), absent in large subapicolateral boss and on rim; T2 disc shiny, with punctures fine, moderately dense (IS = 1–2 PD), apical rim weakly coriarious, with punctures minute, sparse (IS = 2–4 PD), obscure.

STRUCTURE. Face length /width ratio 0.83 (±0.02 SD); clypeus apicolateral denticles low rounded knobs; gena/eye width ratio 0.88 (± 0.07 SD). Pronotal angle obtuse; intertegular span 0.93 (± 0.08 SD) mm; mesoscutum length /width ratio 0.86 (± 0.04 SD); mesoscutum/scutellum length ratio 2.83 (± 0.25 SD); scutellum/metanotum length ratio 1.61 (± 0.16 SD); metanotum/metapostnotum length ratio 0.66 (±0.06 SD); forewing with 3 submarginal cells; tegula enlarged, reaching posterior margin of mesoscutum in dorsal view; inner posterior margin straight; tegula length 0.41 (± 0.03 SD) mm, width 0.23 (±0.02 SD) mm; propodeum lateral carinae not reaching dorsal margin; oblique carina strong, straight. T2 depressed apical rim less than 50% of tergum. (n = 10)

VARIATION. The tegula punctures can vary from sparse (IS = 1–3 PD) to entirely dense (IS <1 PD), the mesoscutum punctures can vary from moderately sparse (IS = 1–2 PD) to dense (IS <1 PD), the mesoscutum and mesepisternum are usually dull and strongly tessellate or imbricate but can be somewhat shiny; the metapostnotum can vary from shiny with coarse rugae to dull with fine rugae, and the tegula and metasoma can vary from dark brown to bright orange.

Male

COLOURATION. Head and mesosoma blue to blue-green; clypeus apex black; labrum black; mandible orange with black base and red apex; flagellum dark reddish brown dorsally, light brown ventrally. Pronotal lobe dark reddish brown; legs dark reddish brown with femur-tibia joints and tarsi becoming light brown; tegula reddish brown; wing membrane hyaline, veins dark brown. Metasoma black with depressed apical rims of terga and sterna reddish brown, downcurved lateral areas of terga becoming translucent brown.

PUBESCENCE. Body pile colour white. Tomentum dense on face below eye emargination, pronotal collar and lobe, and space between pronotal lobe and tegula; very sparse on gena, preëpisternum, and T2–T3 basolaterally. Mesoscutum pubescence simple to moderately plumose. Wing setae dark, short and dense. Sterna pubescence short (~1 OD), moderately plumose, sparse.

SURFACE SCULPTURE. Clypeus shiny, with punctures dense (IS <1 PD); supraclypeal area shiny to weakly imbricate, with punctures dense (IS <1 PD) with impunctate median line 1 PD or more wide; paraocular area shiny, with punctures dense (IS <1 PD); frons reticulate, with punctures crowded (IS = 0 PD); vertex shiny, with punctures dense laterally (IS <1 PD), moderately dense medially (IS = 1–2 PD); gena shiny, with punctures fine, moderately sparse (IS = 1–2 PD); postgena shiny to weakly lineate. Tegula punctures dense (IS <1 PD), becoming fine and moderately sparse laterally (IS = 1–2 PD); mesoscutum shiny, becoming weakly tessellate anteromedially, with punctures dense (IS ≤ 1.5 PD), becoming crowded marginally (IS = 0 PD); scutellum shiny, with punctures dense (IS ≤1.5 PD), becoming crowded marginally (IS = 0 PD); metanotum shiny to weakly imbricate and densely punctate (IS ≤1 PD); metapostnotum shiny to finely reticulate, with rugae strong, anastomosing, reaching posterior margin; preëpisternum areolate; hypoepimeron shiny, with punctures crowded (IS = 0 PD); mesepisternum shiny, with punctures dense (IS <1 PD); metepisternum areolate; propodeum lateral surface areolate to rugulose, with punctures crowded (IS = 0 PD), posterior surface shiny with crowded punctures (IS = 0 PD), becoming areolate laterally. T1 anterior slope shiny, disc shiny, with punctures fine, moderately sparse (IS = 1–3 PD), absent in small subapicolateral boss and on rim; T2 disc shiny, with punctures fine, moderately sparse (IS = 1–2 PD), apical rim shiny, with punctures absent.

STRUCTURE. Face length/width ratio 0.85 (±0.03 SD); gena/eye width ratio 0.67 (± 0.06 SD). Pronotal angle obtuse; intertegular span 0.68 (± 0.05 SD) mm; mesoscutum length/width ratio 0.95 (± 0.03 SD); mesoscutum/scutellum length ratio 2.68 (± 0.09 SD); scutellum/metanotum length ratio 1.84 (±0.13 SD); metanotum/metapostnotum length ratio 0.7 (± 0.07 SD); forewing with 3 submarginal cells; tegula enlarged, nearly reaching posterior margin of mesoscutum in dorsal view; inner posterior margin weakly concave; tegula length 0.35 (±0.02 SD) mm, width 0.19 (± 0.01 SD) mm; propodeum lateral carinae not reaching dorsal margin; oblique carina absent. (n = 10)

GENITALIA. As in Fig. 76D . Gonocoxite nearly 2 times as broad as gonostylus. Gonostylus rounded, slightly concave on outer margin, with sparse long setae dorsally and short setae along inner margin. Penis valves parallel. Retrorse lobe rounded, about 3 times as long as broad, with sparse short setae on basal half and apical margin.

VARIATION. The tegula can sometimes be entirely densely punctate (IS <1 PD), the mesoscutum punctation can vary from mostly dense (IS ≤1 PD) to sparse (IS = 1–3 PD), the metapostnotum can vary from shiny with strong rugae to dull with fine rugae, and the head and mesosoma can vary from blue to golden-green.

Range

Western Colorado, Utah, and southern Nevada , south along the Colorado River valley and east along the Gila River valley to Phoenix, Arizona ( Fig. 17 ).

Floral hosts

ASTERACEAE : Chrysothamnus Nutt. : C. greenei (A.Gray) Greene • Cirsium Mill. : C. rydbergii Petr. • Pluchea Cass. • BRASSICACEAE : Dimorphocarpa Rollins : D. wislizeni (Engelm.) Rollins • Lepidium • Streptanthella Rydb. : S. longirostris (S.Watson) Rydb. • Thelypodium Endl. : T. integrifolium (Nutt.) Endl. • CLEOMACEAE : Cleome L.: C. serrulata Pursh • FABACEAE : Medicago : M. sativa • Melilotus : M. officinalis : M. o. subsp. alba • MALVACEAE : Gossypium • Sphaeralcea • PLANTAGINACEAE : Penstemon : P. humilis Nutt. ex A.Gray • SALICACEAE : Salix : S. exigua Nutt. • SOLANACEAE : Lycium L.: L. fremontii A.Gray • Solanum L.: S. elaeagnifolium Cav. • TAMARICACEAE : Tamarix .

DNA barcodes

Eleven confirmed sequences available, three haplotypes (BOLD process IDs: BHTT023-09, DLII890-07, DLII1067-07, DLII1099-07, DLII1232-08, DLII1233-08, DLII1694-09, DLII1696-09 (haplotype 1); DLII940-07, DLII1677-09 (haplotype 2); DLIII124-18 (haplotype 3)). There is a large amount of divergence within these sequences (2.29% maximum intraspecific p-distance). They are closest in terms of p-distance to the L. stictaspis species complex (0% minimum interspecific p-distance). No fixed nucleotide substitutions distinguish all L. diabolicum sp. nov. from all other Nearctic species of the L. gemmatum complex, but three fixed substitutions distinguish haplotype 1: 33(G), 111(C), and 588(C) (Supp. file 2).

Comments

Some specimens with the tegula slightly larger and more densely punctate than usual are extremely difficult to separate from L. stictaspis , and are therefore excluded from paratype status. These specimens may be hybrids or a separate, cryptic species. The barcoded haplotype 3 specimen is one such specimen, but the haplotype 2 specimens are morphologically indistinguishable from haplotype 1 (which includes the holotype). It is thought that haplotype 1 is the ʻnaturalʼ barcode sequence of L. diabolicum sp. nov., and the additional haplotypes are a result of introgression or incomplete lineage sorting.

Figures

Fig. 15. Lasioglossum (D.) diabolicum sp. nov., ♀, holotype (BBSL409921). A. Dorsal habitus. B. Lateral habitus. C. Face. D. Metasoma. Scale bars = 1 mm.

Fig. 16. Lasioglossum (D.) diabolicum sp. nov., ♂ (BBSL488442). A. Dorsal habitus. B. Lateral habitus. C. Face. D. Metasoma and propodeum. Scale bars = 1 mm.

Fig. 17. Georeferenced collection records of Lasioglossum (D.) diabolicum sp. nov. (black squares) and predicted distribution by maximum entropy ecological niche modelling in Maxent (colour shading). Warmer colours indicate higher cloglog probability of occurrence.

Fig. 76. Male genitalia illustrated in dorsal view and positioned such that the gonostylus is parallel to the plane of vision. Retrorse lobes are also illustrated separately to the bottom left of each figure in lateral view, positioned parallel to the plane of vision. A. Lasioglossum (D.) angelicum sp. nov.B. L. (D.) coactus (Cresson, 1872). C. L. (D.) deludens sp. nov. D. L. (D.) diabolicum sp. nov.E. L. (D.) gaudiale (Sandhouse, 1924). F. L. (D.) gloriosum sp. nov. (the retrorse lobe was not visible for illustration). G. L. (D.) helianthi (Cockerell, 1916). H. L. (D.) holzenthali sp. nov. I. L. (D.) indagator sp. nov. J. L. (D.) magnitegula sp. nov. K. L. (D.) perparvum (Ellis, 1914). L. L. (D.) profoundum sp. nov. M. L. (D.) pseudotegulare (Cockerell, 1896). N. L. (D.) rufodeludens sp. nov. This genital capsule was damaged during dissection and some details may be slightly distorted.O. L. (D.) stictaspis (Sandhouse, 1923) (holotype) (reproduced from Gardner & Gibbs 2022). P. L. (D.) tegulariforme (Crawford, 1907) (reproduced from Gardner & Gibbs 2022). Scale bars = 0.25 mm.

Fig. 87. Tegulae. A. Lasioglossum angelicum sp. nov., ♀, large with inner posterior margin concave and distinct posterior projection (outline and arrow). B. L. diabolicum sp. nov., ♀, small with inner posterior margin nearly straight and no posterior projection (outline). Scale bars = 0.5 mm.

Fig. 97. T1–T3. A. Lasioglossum holzenthali sp. nov., ♀, with thin, sparse basal bands of tomentum and apical rims deeply and distinctly punctate. B. L. diabolicum sp. nov., ♀, with thick, dense basal bands of tomentum and apical rims impunctate. Scale bars = 1 mm.

Fig. 98. Mesepisternum. A. Lasioglossum diabolicum sp. nov., ♀, shiny with distinct round punctures. B. L. tegulare (Robertson, 1890), ♀, dull and rugulose. Scale bars = 0.5 mm.

Fig. 99. Mesepisternum. A. Lasioglossum ellisiae (Sandhouse, 1924), ♀, punctures similar to hypoepimeron. B. L. diabolicum sp. nov., ♀, punctures slightly larger and coarser than on hypoepimeron. Scale bars = 0.5 mm.

Fig. 100. Tegulae. A. Lasioglossum diabolicum sp. nov., ♀, with blunt posterior angle (white outline and arrow). B. L. stictaspis (Sandhouse, 1923), ♀, with rounded posterior projection (white outline and arrow). Scale bars = 0.5 mm.

Fig. 117. T2. A. Lasioglossum egulare (Robertson, 1890), ♂, with dense punctures up to premarginal line sharply contrasting with impunctate apical rim. B. L. diabolicum sp. nov., ♂, with punctures becoming more sparsely punctate near and on premarginal line and not sharply contrasting with apical rim. Scale bars = 0.5 mm.

Fig. 119. Pleura. A. Lasioglossum lepidii (Graenicher, 1927), ♂, preëpisternum and hypoepimeron more finely punctate than mesepisternum. B. L. diabolicum sp. nov., ♂, preëpisternum and hypoepimeron as coarsely punctate as mesepisternum. Scale bars = 0.5 mm.

Fig. 120. Mesoscutum. A. Lasioglossum ellisiae (Sandhouse, 1924), ♂, evenly punctate with most IS = 1 PD. B. L. diabolicum sp. nov., ♂, more coarsely and unevenly punctate. Scale bars = 0.5 mm.