Lasioglossum (Dialictus) rufulipes (Cockerell)

Gibbs, Jason, 2011, Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini), Zootaxa 3073, pp. 1-216 : 171-175

Lasioglossum (Dialictus) rufulipes (Cockerell)

( Figures 186–190 )

Halictus (Chloralictus) rufulipes Cockerell, 1938: 3 . Ƥ.

Holotype. Ƥ CANADA, Saskatchewan, Lake Waskesiu, beginning of portage to Heart Lakes, 31.viii.1936, (T. & W. Cockerell); [ AMNH]. Examined.

Taxonomy. Michener, 1951: Lasioglossum (Chloralictus) rufulipes , p. 1117 (catalogue); Knerer and Atwood, 1964: Dialictus sandhouseae Ƥ, p. 7 (description, misdet.); Hurd, 1979: Dialictus rufulipes , p. 1971 (catalogue); Moure & Hurd, 1987: Dialictus rufulipes , p. 128 (catalogue); Lasioglossum (Evylaeus) rufulipes , p. 15 (tax. notes).

Diagnosis. Both sexes of L. rufulipes can be distinguished from all Lasioglossum North of Mexico by the following diagnostic combination: head and mesosoma metallic; mesoscutal punctation fine, sparse between parapsidal lines; metapostnotum nearly as long as mesoscutellum; lateral and posterior propodeal surfaces completely separated by lateral carina (as in Figs. 1 , 28 B); oblique carina strong; and metasomal terga brown with reddish brown highlights. Female L. rufulipes can be further distinguished by T1 acarinarial fan absent ( Fig. 187 ) and T4 with moderately sparse tomentum. Male L. rufulipes can be further distinguished by labrum, mandible and distal half of clypeus yellow ( Fig. 188 B), mesepisternum impunctate, gonobase ventral rim entire ( Fig. 190 A), and retrorse lobe narrow. Lasioglossum testaceum is most similar but can be distinguished by metasomal terga yellow-orange in females ( Fig. 213 A) and fine mesepisternal punctation of males.

Redescription. FEMALE. Length 5.12–5.31 mm; head length 1.37–1.46 mm; head width 1.51–1.56 mm; forewing length 4.03–4.33 mm.

Colouration. Head and mesosoma pale, golden green with bluish to purplish reflections on the face and mesopleuron. Labrum reddish brown. Mandible yellow to yellowish brown, apex red, base blackish brown. Clypeus with apical half reddish brown, basal half, and supraclypeal area bronze. Antenna brown, F3–F10 with ventral surface brownish yellow. Tegula brownish yellow to reddish brown. Wing venation and pterostigma amber to brownish yellow. Wing membrane faintly dusky. Legs brown, except tibial base, protibial anterior face, metabasitarsus, meso- and distitarsi brownish yellow. Propodeum dorsal surface purplish. Metasoma reddish brown, terga and sterna with apical margins translucent brownish yellow.

Pubescence. Dull white. Sparse. Head and mesosoma with moderately dense woolly hairs (1–1.5 OD), longest on genal beard, metanotum, and mesopleuron (1.5–2.5 OD). Face with sparse subappressed tomentum not obscuring surface. Gena without tomentum. Pronotal lobe and dorsolateral angle with dense tomentum. Propodeum with moderately dense plumose hairs on lateral and posterior surfaces (1.5–2 OD). Metasomal terga with sparse fine hairs. T1 acarinarial fan absent. T1 with erect hairs (1 OD) only. T3 with narrow basal fasciae of appressed tomentum. T3–T4 apical margins very with very sparse apical fringes.

Surface sculpture. Face imbricate, punctation fine, shallow. Clypeus weakly imbricate, punctation moderately sparse (i=1–2d). Supraclypeal area moderately dense (i=1–1.5d). Lower paraocular area with punctation dense, obscure (i≤d). Antennocular area with punctation sparse (i=1–3d). Upper paraocular area and frons punctate-reticulate. Ocellocular area punctation obscure, minute (i≤d). Gena and postgena lineolate. Mesoscutum imbricate, punctation very fine and shallow, moderately sparse between parapsidal lines (i=1–2d), moderately dense laterad of parapsidal lines (i=1–1.5d), anterolateral portions obscurely, contiguously punctate. Mesoscutellum similar to mesoscutum, submedial punctation moderately dense (i=1–1.5d). Axilla punctate. Metanotum imbricate. Preëpisternum rugulose. Hypoepimeral area imbricate, obscurely punctate. Mesepisternum upper half rugulose, lower half tessellate-imbricate. Metepisternum with upper half rugoso-carinulate, lower half imbricate. Metapostnotum anastomosing rugose. Propodeum with dorsolateral slope weakly imbricate, lateral surface tessellate, posterior surface tessellate-imbricate. Metasomal terga weakly coriarious, T1 virtually impunctate, T2–T4 punctation on basal half sparse, obscure (i=2–4d), apical half impunctate (except along premarginal line).

Structure. Head wide (length/width ratio = 0.90–0.94). Eyes weakly convergent below (UOD/LOD ratio = 1.14– 1.19). Clypeus ½ below suborbital tangent, apicolateral margins strongly convergent. Antennal sockets somewhat distant (IAD/OAD> 0.6). Frontal carina ends 2 OD from median ocellus. IOD greater than OOD. Hypostomal carinae parallel. Pronotum with dorsolateral angle obtuse. Pronotal ridge broadly rounded, interrupted by oblique sulcus. Mesoscutum with anteromedial margin very weakly emarginate. Tegula ovoid. Procoxa and protrochanter unmodified. Inner metatibial spur pectinate with 4–5 short, narrow branches (not including apex of rachis). Metapostnotum lunate, elongate (MMR = 1.12–1.21), posterior margin narrowly rounded onto posterior surface. Propodeum strongly carinate, lateral carina reaching dorsal margin.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length 5.49–5.61 mm; head length 1.37–1.44 mm; head width 1.44–1.51 mm; forewing length 4.27–4.33 mm.

Colouration. Head and mesosoma bluish green. Labrum, mandibles, and clypeus distal half pale yellow, clypeus yellow mark extending upward along midline. Flagellum with ventral surface pale brownish yellow. Legs brown, except pro- and mesotibia mostly brownish yellow, outer surfaces with elongate central brown area, tarsi and metatibial base and apex extensively pale brownish yellow. Metasoma brown, infused with brownish red.

Pubescence. Dull white. Sparse. Lower paraocular area with appressed tomentum obscuring surface. Upper clypeus and lower supraclypeal area with scattered plumose hairs. S2–S5 with sparse apical fringes.

Surface sculpture. Ocellocular area rugulose. Lower surface of mesepisternum obscurely punctate (i=1–2d). Propodeum dorsolateral slope, posterior portion of lateral surface of propodeum, and posterior surface of propodeum strongly rugose. T1–T2 polished, remainder of metasomal terga weakly coriarious. Metasomal terga punctation sparse on basal half (i=1–4d), apical half impunctate (except along premarginal line).

Structure. Head wide (length/width ratio = 0.95–0.97). Eyes strongly convergent below (UOD/LOD ratio = 1.44– 1.54). Clypeus 2/3 below suborbital tangent, apicolateral margins convergent. Antennal sockets distant (IAD/OAD> 1.8). Pedicel shorter than F1. F2 length 1.9–2.2X F1. F2–F10 elongate (length/width ratio = 1.63–1.93). Metapostnotum moderately elongate (MMR = 1.16–1.20), posterior margin sharply angled onto posterior propodeal surface.

Terminalia . S7 with median lobe short, acuminate, apex narrowly rounded ( Fig. 190 C). S8 with apical margin weakly convex ( Fig. 190 C). Genital capsule as in Fig. 190 A, B. Gonobase with ventral arms connected. Gonostylus small, covered with fine hairs, dorsal setae elongate. Retrorse lobe narrow, parallel-sided, covered with fine hairs. Penis valve narrow apically.

Range. Quebec west to Alberta, Yukon Territory, south to Minnesota ( Fig. 191 ). USA: MI, MN. CANADA: AB, MB, NT, ON, PQ, YT.

Additional material examined. CANADA: ALBERTA: 35ƤƤ Waterton, 8.vi.1962 (K.C. Herman); 1Ƥ Waterton, 24.vi.1962 (W.R.M. Mason); 3ƤƤ 8 mi E Morley, 26.vi.1962 (K.C. Herman); 13 15 mi E Morley, 10.vii.1962 (K.C. Herman); 4ƤƤ Twin Butte, 10.vi.1962 (K. Herman); [ CNC]; 1Ƥ Barrier Lake, 22.v.1988 (L. Packer); [ PCYU]; 2ƤƤ Edmonton, 25.v.1986 (D. Blades); 2ƤƤ Fort MacKay: bridge, riparian forest hillside, 5.v.1979 (G.J. Hilchie & J.K. Ryan); 13 Thickwood Hills road, 22.viii.1978 (J.K. Ryan & G.J. Hilchie); [ PMAE]; MANITOBA: 1Ƥ Gillam, 20.vi.1950 (J.F. McAlpine); 1Ƥ Gillam, 19.vii.1950 (J.F. McAlpine); 333 Turtle Mt., 22.vii.1953 (Brooks & Kelton); [ CNC]; NORTH- WEST TERRITORIES: 2ƤƤ Normal Wells, 9.vi.1949 (W.R.M. Mason); [ CNC]; 1Ƥ Mackenzie Dist., Norman Wells, N65°15ʹ15ʹʹ W126°41ʹ15ʹʹ, 22.viii–1.ix.2005 (D. Currie & R. Popko); [ ROM]; ONTARIO: 1Ƥ Cane, 22.vi.1961 (G. Knerer); 13 Upsala, 14.viii.1962 (G. Knerer); [ BMNH];1Ƥ Upsala, 14.viii.1962 (G. Knerer); 1Ƥ Upsala, 18.viii.1962 (G. Knerer); 13 Black Sturg. Lake, 1–15.viii.1956 (Linberg); [ CUIC]; 733 3ƤƤ (1 stylopized), Upsala, 14.viii.1962 (G. Knerer); 2ƤƤ Cane, 22.vi.1961 on Salix, (G. Knerer) ; 7ƤƤ Kirkland Lake, 21.vi.1961 on Salix, (G. Knerer) ; 233 Torquis, 10.viii.1961 (G. Knerer); 1Ƥ63 Hearst, 17.viii.1963 (G. Knerer); 13 Kabinakagami R., 17.viii.1963 (G. Knerer); [ ROM]; QUEBEC: 1Ƥ W of Normandin, N48°51´38.9´´ W72°37´0.9´´, 180 m, 8.vi.2009 (M. Chagnon); [ PCYU]; YUKON TERRITORY: 3ƤƤ 1933 Dawson, 1100 ft., 18.viii.1949 (P.F. Bruggemann); [ CNC]; 433 Julie’s farm, 4.viii.1992 (J. Taylor); [ PCYU]; USA: MICHIGAN: 13 Michigamme, 8.viii.1936 (C. Sabrosky); [ NMNH]; MINNESOTA: 1Ƥ Beltram Co., Kelliher, 2.viii.1951 (R.L. Fischer); [ CUIC].

Floral records. APOCYNACEAE : Apocynum androsaemifolium , ASTERACEAE : Anaphalis , Solidago , ONAGRACEAE : Epilobium , ROSACEAE : Potentilla , Prunus , Spiraea , SALICACEAE : Salix .

Comments. Uncommon. This is evidently a boreal species.

Lasioglossum rufulipes and L. testaceum were excluded from the revision of Canadian L. ( Dialictus ) based on an unpublished morphological study which suggested these two species belonged in the subgenus L. ( Evylaeus ). In particular, the shape of the genital capsule appears more similar to those of L. ( Evylaeus ). Now, based on additional unpublished molecular phylogenetic results, it is evident this subgeneric change was premature and additional study is required. The two species are included here in the subgenus Dialictus , following traditional usage, until the subgeneric limits of Dialictus and Evylaeus are stabilized.

Knerer and Atwood (1964) incorrectly referred to the female of L. rufulipes using the epithet sandhouseae Michener (as D. sandhouseae ). For additional, information see the comment for L. testaceum below.

Figures

FIGURE 1. Propodeum and metapostnotum of female Lasioglossum with strong propodeal carinae. Metapostnotum (M). Propodeum, dorsolateral slope (D), posterior surface (P), lateral surface (L), oblique carina (oc), lateral carina (lc). (From Gibbs 2010 b).

FIGURE 28. Propodeal carinae (A) weak, (B) strong. (From Gibbs 2010 b).

FIGURE 186. Lasioglossum rufulipes (Cockerell) female, (A) lateral habitus, (B) face. Scale bars = 1 mm.

FIGURE 187. Lasioglossum rufulipes (Cockerell) female, dorsal view of mesosoma.

FIGURE 188. Lasioglossum rufulipes (Cockerell) male, (A) lateral habitus, (B) face. Scale bars = 1 mm.

FIGURE 189. Lasioglossum rufulipes (Cockerell) male, dorsal view of mesosoma.

FIGURE 190. Lasioglossum rufulipes (Cockerell) male terminalia, (A) ventral view, (B) dorsal view. Scale bar = 0.5 mm.

FIGURE 191. Distribution map of Lasioglossum rufulipes (stars) and L. testaceum (circles).

FIGURE 213. Lasioglossum testaceum (Robertson) female, (A) lateral habitus, (B) face. Scale bars = 1 mm.