Lasioglossum (Dialictus) raleighense (Crawford)

Gibbs, Jason, 2011, Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini), Zootaxa 3073, pp. 1-216 : 160-163

Lasioglossum (Dialictus) raleighense (Crawford)

( Figures 170–173 )

Halictus raleighensis Crawford, 1932: 73 . Ƥ.

Holotype. Ƥ USA, North Carolina, Raleigh , 5.vi.1923, on Baptisia tinctoria, (T.B. Mitchell) ; [ AMNH]. Examined.

Taxonomy. Michener, 1951: Lasioglossum (Chloralictus) raleighense Michener, 1951: 1117 (catalogue); Mitchell, 1960: Dialictus raleighensis Ƥ3, p. 416 (redescription); Krombein, 1967: Lasioglossum (Dialictus) raleighense , p. 465 (catalogue); Moure and Hurd, 1987: Dialictus raleighensis , p. 126 (catalogue).

Diagnosis. Female L. raleighense can be recognised by the following diagnostic combination: clypeus and supraclypeal area flat, dull due to microsculpture ( Fig. 170 B); mesoscutal punctation dense (i<d) ( Fig. 171 ); metasomal terga brown, tomentum, moderately sparse, and apical impressed areas with deep, distinct punctation. They are most similar to L. batya , which has supraclypeal area polished and shiny ( Fig. 69 B).

Male L. raleighense can be recognised by the following diagnostic combination: clypeus yellow distally ( Fig. 172 B), supraclypeal area imbricate, flagellomeres short (F2–F10 length/width ratio = 1.13–1.18) ( Fig. 172 B), mesoscutal punctures contiguous, and metasomal terga with apical impressed areas deeply and distinctly punctate. They are most similar to L. batya , which has supraclypeal area polished and shiny.

Redescription. FEMALE. Length 4.60–4.96 mm; head length 1.37–1.44 mm; head width 1.34–1.42 mm; forewing length 2.96–3.15 mm.

Colouration. Head and mesosoma pale green to bluish green. Clypeus with apical half blackish brown. Supraclypeal area bronze. Antenna dark brown, flagellum with ventral surface reddish brown to orange-yellow. Tegula amber. Wings faintly dusky, venation and pterostigma reddish brown. Legs brown, except medio- and distitarsi reddish brown. Metasomal terga golden brown with narrow reddish rim, sterna brown, apical margins pale, translucent yellow.

Pubescence. Dull white. Head and mesosoma with moderately dense woolly hairs (1–1.5 OD), longest on genal beard, metanotum, and mesopleuron (2–2.5 OD). Paraocular area and gena with subappressed tomentum partially obscuring surface. Propodeum with moderately dense plumose hairs on lateral and posterior surfaces (2–2.5 OD). Metasomal terga with moderately dense, fine hairs. T1 acarinarial fan complete. T1 dorsolateral portion with sparse tomentum. T2–T3 laterally and T4 entirely with sparse tomentum not obscuring surface. T2 apicolateral and T3–T4 apical margins with sparse fringes.

Surface sculpture. Face tessellate-imbricate, punctation fine. Clypeus punctation evenly spaced (i=1–2d). Supraclypeal area imbricate, punctation moderately sparse (i=1–3d). Lower paraocular and antennocular areas with punctation dense (i≤d). Upper paraocular area, frons and ocellocular area punctate-reticulate. Gena and postgena lineolate. Mesoscutum and mesoscutellum tessellate, punctation dense throughout (i≤d). Axilla punctate-reticulate. Metanotum imbricate. Preëpisternum rugose. Hypoepimeral area reticulate-rugulose. Mesepisternum reticulate-rugulose, weakly rugulose posteriorly. Metepisternum with dorsal portion rugoso-carinulate, ventral half imbricate. Metapostnotum with weak rugae poorly defined amidst tessellate interstices, posterior margin tessellate-granular. Propodeum with dorsolateral slope tessellate, lateral surface and posterior rugulose-imbricate. Metasomal terga polished, apical impressed areas weakly coriarious, punctation dense and distinct throughout (i=1–1.5d).

Structure. Head round to elongate (length/width ratio = 1.00–1.03). Eyes strongly convergent below (UOD/ LOD ratio = 1.44–1.48). Clypeus ½ below suborbital tangent, apicolateral margins weakly convergent. Antennal sockets close (IAD/OAD <0.5). Frontal line carinate, ending 2OD below median ocellus. Gena narrower than eye. Inner metatibial spur pectinate with 3–4 branches. Metapostnotum truncate (MMR ratio = 1.30–1.44), lateral margin distinct, posterior margin weakly angled onto posterior surface. Propodeum with oblique carina fine, lateral carina not reaching dorsal margin.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length 3.39–3.96 mm; head length 1.30–1.32 mm; head width 1.21–1.25 mm; forewing length 2.78–2.84 mm.

Colouration. Labrum, mandible and distal margin of clypeus brownish yellow. Flagellum with ventral surface brownish yellow. Legs brown, except tibial bases and apices and tarsi brownish yellow.

Pubescence. Paraocular area below eye emargination with tomentum obscuring surface. S2–S4 with moderately elongate woolly hairs (1.5–2 OD).

Surface sculpture. Clypeus and supraclypeal area imbricate, punctation moderately dense (i=1–1.5d). Mesepisternum reticulate-punctate dorsally. T1 anterior surface with punctures evenly spaced (i=1–2.5d).

Structure. Head elongate (length/width ratio = 1.06–1.07). Eyes strongly convergent below (UOD/LOD ratio = 1.67). Clypeus 2/3 below suborbital tangent, apicolateral margins subparallel. Antennal sockets distant (IAD/OAD = 1.0). Frontal line carinate, ending 2 OD below median ocellus. Pedicel subequal to F1. F2 length 1.0–1.1X F1. F2–F10 short (length/width ratio = 1.13–1.18). Metapostnotum moderately truncate (MMR ratio = 1.22–1.41), posterior margin rounded onto posterior surface.

Terminalia . S7 with median lobe nearly parallel sided, apex rounded ( Fig. 173 ). S8 with apicomedial margin weakly convex ( Fig. 173 ). Genital capsule as in Fig. 173 . Gonobase with ventral arms widely separated. Volsella short, nearly round. Gonostylus small, dorsal setae elongate. Retrorse lobe elongate, strongly attenuated apically, apex recurved.

Range. North Carolina south to Georgia ( Fig. 174 ). USA; GA, NC.

Additional material examined. USA: GEORGIA: 4ƤƤ 13 Forsyth, 23–30.ix.1970 (F.T. Naumann); 1Ƥ Rabun Bald, 4700 ft., 16.vii ..1957 (W.R. Richards); 1Ƥ Rabun Bald, 9.viii.1957 (L.A. Kelton); [ CNC]; 3ƤƤ Jasper Co., 18.vii.2008 (J. Hanula & S. Horn); [ PCYU]; NORTH CAROLINA: 1Ƥ Wayne Co., 23.v.1954 (T.B. Mitchell); [ CUIC]; 2ƤƤ Harnett Co., 18.v.1935 (H.F. Schoof); 1Ƥ Wayne Co., 23.v.1954 (T.B. Mitchell); 3ƤƤ Raleigh, 17.v.1942 (T.B. Mitchell); 1Ƥ Southern Pines, 23.ix.1950 (T.B. Mitchell); [ NCSU].

Floral records. FABACEAE : Baptisia tinctoria , Galactia , Tephrosia ; POLYGONACEAE : Polygonum .

DNA Barcode. Available. Multiple sequences.

Comments. Uncommon.

Lasioglossum raleighense is used in a more restricted sense than in previous studies (e. g. Mitchell 1960), due to the description of the related species L. batya (above).

Figures

FIGURE 69. Lasioglossum batya Gibbs female, (A) lateral habitus, (B) face. Scale bars = 1 mm.

FIGURE 170. Lasioglossum raleighense (Crawford) female, (A) lateral habitus, (B) face. Scale bars = 1 mm.

FIGURE 171. Lasioglossum raleighense (Crawford). dorsal view of mesosoma.

FIGURE 172. Lasioglossum raleighense (Crawford) male, (A) lateral habitus, (B) face. Scale bars = 1 mm.

FIGURE 173. Lasioglossum raleighense (Crawford) male terminalia, (A) ventral view, (B) dorsal view. Scale bar = 0.5 mm.

FIGURE 174. Distribution map of Lasioglossum raleighense (stars) and L. reticulatum (circles).