Lasioglossum (Dialictus) clastipedion, Gardner & Gibbs, 2020

Gardner, Joel & Gibbs, Jason, 2020, The ‘ red-tailed’ Lasioglossum (Dialictus) (Hymenoptera: Halictidae) of the western Nearctic, European Journal of Taxonomy 725, pp. 1-242 : 46-52

Lasioglossum (Dialictus) clastipedion sp. nov.

urn:lsid:zoobank.org:act:1C13534B-7D94-4001-844A-C75CDAC05B63

Figs 22–24 , 90B , 96B , 104B

Diagnosis

Females of Lasioglossum clastipedion sp. nov. can be recognized by the characters for the Lasioglossum clematisellum species complex (below), in addition to the metasomal terga with dense tomentum on T2–3 basolaterally and T4 throughout, frons and vertex usually with weak microsculpture slightly dulling the surface, scutum with most hairs relatively densely plumose and punctures of anteromedian margin distinct, and head and mesosoma often golden-green with more yellowish hair dorsally. They are most similar to L. clematisellum and can only be separated with great difficulty, especially if specimens are worn. Females of L. clematisellum have the metasomal terga with no tomentum; this is the most reliable character. In addition, females of L. clematisellum usually have the scutum with thinner and more weakly plumose hair and less distinct punctures of the anteromedian margin, and the head and mesosoma blue-green with all white hair.

Males of L. clastipedion sp. nov. can be recognized by the characters for the Lasioglossum clematisellum species complex (below) in addition to T2–3 with sparse basolateral tomentum, scutum with most hairs densely plumose, appearing thickened, and frons with dense punctures (i <1 pd). They are most similar to L. clematisellum , L. julipile sp. nov., and L. perditum sp. nov. Males of L. clematisellum have T2–3 with no tomentum and scutum with most hairs thin and weakly plumose. Males of L. julipile sp. nov. and L. perditum sp. nov. have the frons more sparsely punctate (i=1–3 pd). Worn specimens are extremely difficult to distinguish from L. clematisellum .

Etymology

The specific epithet clastipedion is formed from the Latinized Greek adjective ‘ klastos ’ (‘broken’, ‘shattered’) and the Greek genitive plural noun ‘ pedion ’ (‘of plains’). It refers to this species’ restricted distribution in the canyonlands of southern Utah and northern Arizona, which resemble the fictional Shattered Plains of Brandon Sanderson’s novel The Way of Kings. An appropriate translation would be the Shattered Plains sweat bee.

Material examined

Holotype

UNITED STATES – Utah • ♀; Emery Co., Wild Horse Creek N of Goblin Valley; [38.57° N, 110.82° W]; 1463 m a.s.l.; 26–28 Jul. 1982; Parker / Griswold leg.; BBSL.

[Verbatim label: UTAH EmeryCo 4800’ Wild Horse Cr N of GoblinVly VII-26-28-82/Parkers/Griswold // HOLOTYPE / Lasioglossum (Dialictus) clastipedion Gardner and Gibbs ]

Paratypes

UNITED STATES – Arizona • 7 ♀♀; Mojave Co., 11 mi. N of Mt. Trumbull; [36.56° N, 113.14° W]; 9 Jun. 1994; G. Bryant leg.; ex Argemone ; BBSL • 1 ♀; Beaver Dam ; [36.91° N, 113.95° W]; 20 Jun. 1939; Timberlake leg.; ex Eriogonum trichopes ; UCRC • 1 ♀; Fredonia ; [36.94° N, 112.53° W]; 20 Sep. 1956; G.F. Knowlton leg.; ex Medicago sativa ; UAIC . – Utah • 1 ♂; Emery Co., Bell Canyon , San Rafael Reef ; [38.589° N, 110.808° W]; 1524 m a.s.l.; 26 Jul. 1983; F.A. Parker and T. Griswold leg.; CUIC • 1 ♀; Garfield Co., Blind Trail Wash , SSE of Notom; [38.07° N, 111.055° W]; 1615 m a.s.l.; 15 Sep. 1983; J. Parker leg.; BBSL • 1 ♂; same location as for preceding; 15 Sep. 1983; Parker and Griswold leg.; CUIC • 3 ♀♀; Cedar City; [37.68° N, 113.06° W]; 9 May 1961; G.E. Bohart leg.; ex Salix ; BBSL • 3 ♀♀; Washington Co., Central ; [37.42° N, 113.62° W]; 19 Sep. 1956; Knowlton and Goodarzi leg.; ex Chrysothamnus sp.; SEMC • 1 ♀; Garfield Co., Escalante Riv. , 1.3 mi. W of jct. Death Hollow; 37.7808° N, 111.5353° W; 13 May 2001; C. Davidson leg.; ex Tamarix sp.; BBSL • 1 ♀; Kane Co., Glendale ; [37.32° N, 112.6° W]; 13 Apr. 1962; G.F. Knowlton leg.; ex Salix ; SEMC • 1 ♂; Garfield Co., Grand Gulch , Hall Creek ; [37.6° N, 110.87° W]; 1372 m a.s.l.; 22 Aug. 1980; A.S. Menke, F.D. Parker and Kurt A. Menke leg.; CUIC • 1 ♀; Garfield Co., Hog Spr. ; [37.977° N, 110.52° W]; 1341 m a.s.l.; 29 Aug. 1985; T.L. Griswold leg.; BBSL • 2 ♀♀; Kanab ; [37.05° N, 112.53° W]; 6 Aug. 1954; G.T. Knowlton and D.W. Davis leg.; SEMC • 1 ♀; Garfield Co., Pine Creek , 4.5 mi. N of Escalante; 37.9031° N, 111.6686° W; 19 Jun. 2000; O. Messinger leg.; ex Tamarix sp.; BBSL • 5 ♂♂; St. George ; [37.1° N, 113.57° W]; 9 Sep. 1954; G.F. Knowlton leg.; SEMC • 1 ♀; Washington Co., Washington; [37.13° N, 113.51° W]; 15 Apr. 1962; G.F. Knowlton leg.; ex Tamarix ; SEMC • 1 ♂; same collection data as for holotype; CUIC • 1 ♀; Garfield Co., Wiley Creek ; 20 Jun. 2000; F.D. Parker leg.; ex Tamarix ; BBSL • 2 ♀♀; Washington Co.; 37.1997° N, 112.9882° W; 12 May 2011; C. Decker leg.; WRME .

Description

Female

COLOURATION. Head and mesosoma blue-green to golden-green; clypeus apical colour reddish brown to orange; labrum reddish brown to orange; mandible orange with black basal spot or band and red tip; flagellum black to reddish brown dorsally, reddish brown to orange ventrally; pronotal lobe reddish brown to orange; metasoma red to orange with dark spiracular spots on T3–4; legs reddish brown with femur-tibia joints, tibia apices, and tarsi mostly orange; tegula pale amber; wing membrane hyaline, veins with subcosta dark brown, otherwise pale amber.

PUBESCENCE. Body hair colour pale yellow to white. Tomentum dense on paraocular area, gena, pronotal collar and lobe, space between pronotal lobe and tegula, metanotum medially, metepisternum, T3 basally, and T4 throughout; sparse on supraclypeal area, preëpisternum, mesepisternum, and T2–3 basolaterally. Scutum hair densely plumose. Wing hairs light, very short and sparse. Acarinarial fan complete or nearly so, sparse. T2 fringes sparse, T3 fringes sparse.

SURFACE SCULPTURE. Clypeus punctures dense in basal half (i <1 pd), large and irregularly spaced apically (i <2 pd), sculpture shiny, sometimes weakly tessellate basally; supraclypeal area punctures moderately dense (i=1–2 pd), sometimes becoming sparse medially (i=1–4 pd) or dense laterally (i <1 pd), sculpture shiny, sometimes becoming weakly tessellate laterally; paraocular area punctures dense to moderately sparse (i ≤ 2 pd), sculpture shiny; frons punctures dense to moderately sparse (i ≤ 2 pd), sculpture shiny or weakly tessellate; vertex punctures dense (i ≤ 1 pd) and sometimes obscure laterally, sometimes moderately sparse (i=1–2 pd) and distinct medially, sculpture imbricate or weakly so, sometimes shiny medially; gena punctures dense (i ≤ 1 pd), sculpture shiny; postgena sculpture tessellate and sometimes weakly rugulose; tegula punctures absent; scutum punctures moderately dense (i ≤ 2 pd), becoming sparser submedially (i= 1–3 pd) and denser posteromedially (i <1 pd), sculpture shiny to weakly tessellate, becoming more strongly tessellate anteromedially; scutellum punctures dense (i <1 pd), becoming sparser submedially (i = 1–3 pd), diversopunctate, sculpture shiny, sometimes weakly imbricate marginally; metanotum sculpture shiny with fine, crowded punctures (i =0 pd), becoming rugulose laterally; metapostnotum rugae strong, highly anastomosing, reaching margin, sculpture tessellate; preëpisternum sculpture shiny or weakly imbricate with crowded punctures (i=0 pd), becoming areolate ventrally; hypoepimeron punctures dense (i <1 pd), sculpture shiny; mesepisternum punctures dense (i <1 pd), sculpture shiny or weakly imbricate; metepisternum sculpture rugulosolineate dorsally, tessellate and densely, obscurely punctate ventrally; propodeum lateral face sculpture rugulose anteriorly, tessellate posteriorly; propodeum posterior face sculpture tessellate; T1 anterior face sculpture shiny; T1 dorsal surface punctures fine, moderately sparse (i= 1–4 pd), becoming finer or obscure on rim and absent in small apicolateral oval patches, sculpture shiny; T2 disc punctures fine, moderately dense (i =1–3 pd), disc sculpture shiny, rim punctures very fine, sometimes obscure, sparse (i =2–4 pd), rim sculpture shiny to weakly coriarious.

STRUCTURE. Face length/width ratio 0.8 (± 0.03 SD). Clypeus projecting ~50% below suborbital tangent; clypeal area length/width ratio 0.42 (± 0.02 SD); apicolateral denticles low rounded knobs; supraclypeal area length/width ratio 0.72 (± 0.07 SD). Forewing with 3 submarginal cells; pronotal angle obtuse; tegula shape normal. Intertegular distance 0.88 (± 0.05 SD) mm. Scutum length/width ratio 0.78 (± 0.02 SD); scutum/scutellum length ratio 3.06 (± 0.19 SD); scutellum/metanotum length ratio 1.45 (± 0.14 SD); metanotum/metapostnotum length ratio 0.71 (± 0.06 SD). Propodeum lateral carinae not reaching dorsal margin; oblique carina very weak or absent. T2 depressed apical rim length less than 50% of segment. (n= 9)

Male

COLOURATION. Head and mesosoma blue to olive green; clypeus apical colour black to reddish brown; labrum reddish brown to orange; mandible orange with black basal spot and red tip; flagellum reddish brown dorsally, orange ventrally; pronotal lobe reddish brown; metasoma black to dark reddish brown with rims of terga and sterna broadly translucent reddish brown and downcurved lateral areas of terga becoming translucent orange; legs reddish brown with femur-tibia joints, base and apex of tibiae, and tarsi orange; tegula orange; wing membrane hyaline, veins dark to light 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 and T2–3 basolaterally. Scutum hair moderately to densely plumose. Sterna hair short (0.75–1.25 OD), densely plumose, dense and erect. Wing hairs light, short and sparse.

SURFACE SCULPTURE. Clypeus punctures dense to moderately dense (i ≤ 2 pd), sculpture shiny; supraclypeal area punctures dense to moderately dense (i ≤ 2 pd), sculpture shiny; paraocular area punctures dense (i <1 pd), sculpture shiny; frons punctures crowded (i =0 pd), sculpture shiny; vertex punctures moderately dense laterally (i=1–2 pd), sparse medially (i=1–3 pd), sculpture shiny; gena punctures fine, sparse (i= 1–3 pd), obscure, sculpture shiny, becoming weakly ruguloso-lineate posteriorly and ventrally; postgena sculpture imbricate to ruguloso-lineate; tegula punctures absent; scutum punctures dense (i ≤ 1 pd), becoming moderately sparse submedially (i=1–3 pd), sculpture shiny, sometimes becoming weakly tessellate anteromedially; scutellum punctures dense marginally and on median line (i ≤ 1 pd), sparse submedially (i =1–3 pd), sculpture shiny; metanotum sculpture shiny and moderately sparsely punctate (i=1–2 pd); metapostnotum rugae strong, anastomosing, reaching margin, sculpture shiny to weakly imbricate; preëpisternum sculpture shiny with crowded punctures (i =0 pd); hypoepimeron punctures dense (i ≤ 1 pd), sculpture shiny; mesepisternum punctures dense to moderately dense (i <2 pd), sculpture shiny; metepisternum sculpture lineate dorsally, areolate-rugose ventrally; propodeum lateral face punctures obscure, sculpture imbricate to rugulose; propodeum posterior face sculpture rugulose; T1 anterior face sculpture shiny; T1 dorsal surface punctures dense to moderately dense (i ≤ 2 pd), becoming sparse towards rim (i=1–3 pd) and absent or very sparse in small apicolateral oval patches, sculpture shiny; T2 disc punctures dense to moderately dense (i ≤ 2 pd), becoming sparse toward premarginal line (i =1–3 pd), disc sculpture shiny, rim punctures sparse medially (i=1–4 pd), absent laterally, rim sculpture shiny.

STRUCTURE. Face length/width ratio 0.82 (± 0.02 SD). F1:pedicel length ratio 0.97 (± 0.12 SD); F2:F1 length ratio 2.07 (±0.15 SD); F2 length/width ratio 1.71 (± 0.1SD); F9 length/width ratio 1.47 (± 0.06 SD). Forewing with 3 submarginal cells; pronotal angle obtuse; tegula shape normal. Intertegular distance 0.75 (± 0.07 SD) mm. Scutum length/width ratio 0.9 (± 0.05 SD); scutum/scutellum length ratio 2.77 (± 0.16 SD); scutellum/metanotum length ratio 1.73 (± 0.2 SD); metanotum/metapostnotum length ratio 0.69 (± 0.12 SD). Propodeum lateral carinae not reaching dorsal margin; oblique carina absent. (n =9)

GENITALIA. As in Fig. 90B . Gonocoxite relatively narrow, rounded. Gonostylus with a few long hairs. Retrorse lobe broad, spatulate, with very few short hairs.

Range

Southeastern Utah and far northern Arizona ( Fig. 24 ).

Floral records

ASTERACEAE Giseke : Chrysothamnus • FABACEAE Juss. Medicago : M. sativa L. • PAPAVERACEAE Juss. Argemone L. • POLYGONACEAE Juss. Eriogonum Michx. E. trichopes Torr. • SALICACEAE Mirb. Salix L. • TAMARICACEAE Link : Tamarix L.

DNA barcodes

Two sequences available (BOLD process IDs: DLII850-07, DLII1011-07; BIN: BOLD:AAJ1752). The physical specimens associated with these sequences could not be located. However, an approximately 100 bp fragment of a failed sequence from a new specimen of Lasioglossum clastipedion sp. nov. matched these sequences at 100%, and Gibbs’ recollection of the specimens matches L. clastipedion sp. nov. as well. Along with the collection location in Utah, the sequences can be confidently identified.

Lasioglossum clastipedion sp. nov. differs from all other western red-tailed L. ( Dialictus ) by 2 fixed substitutions: 302(C) and 564(G). It differs from L. clematisellum and L. julipile sp. nov. by an additional 9 fixed substitutions: 96(C), 129(T), 219(C), 300(A), 363(C), 402(C), 531(C), 549(C), and 600(C) (Supplementary file 4).

Figures

Fig. 22. Lasioglossum (D.) clastipedion sp. nov., ♀. A. Dorsal habitus. B. Lateral habitus. C. Face. D. Propodeum and metasoma. Scale bars: 1 mm.

Fig. 23. Lasioglossum (D.) clastipedion sp. nov., ♂. A. Dorsal habitus. B. Lateral habitus. C. Face. D. Propodeum and metasoma. Scale bars: 1 mm.

Fig. 24. Georeferenced collection records of Lasioglossum (D.) clastipedion 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.

Fig. 90. Male genitalia. A. Lasioglossum (D.) arenisaltans sp. nov. B. L. (D.) clastipedion sp. nov. C. L. (D.) clematisellum (Cockerell, 1904). D. L. (D.) hudsoniellum (Cockerell, 1919). E. L. (D.) julipile sp. nov. F. L. (D.) lilianae sp. nov. G. L. (D.) mesillense (Cockerell, 1898). H. L. (D.) meteorum sp. nov. I. L. (D.) miltolepoides sp. nov. J. L. (D.) minckleyi sp. nov. K. L. (D.) pallidellum (Ellis, 1914). L. L. (D.) pictum (Crawford, 1902). M. L. (D.) rufornatum sp. nov. N. L. (D.) spivakae sp. nov. O. L. (D.) testaceum (Robertson, 1897).P. L. (D.) vierecki (Crawford, 1904). Q. L. (D.) zephyrus (Smith, 1853). Genitalia are 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.

Fig. 96. T1 anterior face. A. Lasioglossum (D.) testaceum (Robertson, 1897), ♀, acarinarial fan absent with erect hairs throughout. B. L. (D.) clastipedion sp. nov., ♀, acarinarial fan present but weak, with erect hairs restricted to lateral margins. Scale bars: 0.5 mm.

Fig. 104. Propodeum. A. Lasioglossum (D.) pallidellum (Ellis, 1914), ♀, with metapostnotal rugae not reaching the posterior margin. B. L. (D.) clastipedion sp. nov., ♀, with metapostnotal rugae reaching the posterior margin. Scale bar: 0.25 mm.