Lasioglossum (Dialictus) creberrimum (Smith)

Gibbs, Jason, 2011, Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini), Zootaxa 3073, pp. 1-216 : 75-79

Lasioglossum (Dialictus) creberrimum (Smith)

( Figures 85–89 )

Halictus creberrimus Smith, 1853: 72 . Ƥ.

Holotype. Ƥ N. America; [ BMNH]. Examined.

Halictus ashmeadii Robertson, 1892: 269 . Ƥ.

Lectotype. Ƥ USA, Florida, Inverness, 12.ii.1891 (C. Robertson); [INHS: 9989]. Examined. Halictus ashmeadi Cockerell, 1906: 294 (emend.).

Taxonomy. Michener, 1951: Lasioglossum (Chloralictus) ashmeadii , p. 1112, L. (C.) creberrimum , p. 1113 (catalogue); Mitchell, 1960: Dialictus creberrimus 3Ƥ, p. 389 (redescription, key, synonym); Krombein, 1967: Lasioglossum (Dialictus) creberrimum , p. 463 (catalogue); Moure and Hurd, 1987: Dialictus creberrimus , p. 97 (catalogue).

Diagnosis. Female L. creberrimum can be recognised by the following diagnostic combination: head elongate (length/width ratio = 1.05–1.09) ( Fig. 85 B); mesoscutal punctures dense, except along medial line ( Fig. 86 ); metapostnotal rugae very fine, medially obscure among tessellate background ( Fig. 86 ); T1 acarinarial fan without intermixed erect hairs dorsally; and T2 apical impressed area dull with extremely obscure punctures. They are most similar to L. halophitum and L. tamiamense . Female L. halophitum have mesoscutal punctures sparse medially (i=1–3d), only becoming dense adjacent to the parapsidal lines. Female L. tamiamense have T1 acarinarial fan with intermixed erect hairs dorsally and T2 apical impressed area smoother with distinct, but fine punctures.

Male L. creberrimum can be recognised by the following diagnostic combination: head elongate (length/width ratio = 1.19) ( Fig. 87 B); clypeus with distal margin brownish yellow ( Fig. 87 B); and mesoscutal punctures contiguous, except sparser medially (i=1–1.5d) ( Fig. 88 ); mesoscutellar punctures sparser (i=1–1.5d); T1–T2 at most narrowly impunctate at apical margin; and S5 apical margin weakly concave with sparse apicolateral hairs. They are most similar to male L. halophitum and L. tamiamense . Male L. halophitum have clypeus blackish brown distally and mesoscutum sparsely punctate medially (i=1–3d). Male L. tamiamense have mesoscutellar punctures dense (i<d), T1–T2 apical impressed areas impunctate, and S5 apical margin deeply concave with dense apicolateral hairs.

Redescription. FEMALE. Length 3.99–5.45 mm; head length 1.34–1.64 mm; head width 1.27–1.51 mm; forewing length 2.84–3.63 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. Tegula reddish. Wings faintly dusky, venation and pterostigma yellowish brown. Legs brown, except protibial base and medio- and distitarsi reddish brown. Metasomal terga and 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 without subappressed tomentum. 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 apicolateral portion with sparse tomentum. T2–T3 basal and lateral portions, T4–T5 with sparse tomentum obscuring surface. T2–T4 apical margins with moderately sparse fringes.

Surface sculpture. Face tessellate-imbricate, punctation fine. Clypeus punctation (i=1–2.5d). Supraclypeal area with punctation moderately dense (i=1–1.5d). Lower paraocular and antennocular areas with punctation dense (i≤d). Upper paraocular area, frons and ocellocular area punctate-reticulate. Gena and postgena lineolate. Mesoscutum tessellate, punctation dense on medial portion of disc (i=1–1.5d), punctate-reticulate mesad and laterad of parapsidal line and on anterolateral portion. Mesoscutellum weakly imbricate-tessellate, submedial punctation moderately dense (i=1–1.5d). Axilla punctate. Metanotum imbricate. Preëpisternum rugose. Hypoepimeral area rugulose. Mesepisternum rugose, rugulose posteriorly. Metepisternum with dorsal half rugoso-carinulate, ventral half imbricate. Metapostnotum with very weak rugae, posterior margin tessellate-granular. Propodeum with dorsolateral slope carinulate, lateral surface rugulosetessellate, posterior surface tessellate. Metasomal terga weakly coriarious, punctation moderately dense throughout (i=1– 1.5d), very fine and obscure on apical impressed areas.

Structure. Head elongate (length/width ratio = 1.05–1.09). Eyes convergent below (UOD/LOD ratio = 1.21–1.27). Clypeus ½ below suborbital tangent, apicolateral margins weakly convergent. Antennal sockets close (IAD/OAD <0.5). Frontal line carinate, ending 2 OD below median ocellus. Gena narrower than eye. Inner metatibial spur pectinate with 3– 4 branches. Metapostnotum truncate (MMR ratio = 1.37–1.47), posterior margin weakly angled onto posterior surface. Propodeum with oblique carina fine, lateral carina weak, nearly reaching dorsal margin.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length 3.69–4.11 mm; head length 1.37–1.56 mm; head width 1.22–1.28 mm; forewing length 2.66 mm.

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

Pubescence. Paraocular area below eye emargination with tomentum obscuring surface. Clypeus with sparse tomentum not obscuring surface. T2–T4 lateral portions with sparse tomentum. S2–S3 apical halves and S4–S5 apicolaterally with sparse posteriorly directed hairs (1–1.5 OD).

Surface sculpture. Mesoscutal punctation sparse on posterior half (i=1–2.5d). Mesoscutellar punctation moderately sparse (i=1–3d). Metasomal terga with apical impressed areas sparsely punctate.

Structure. Head very elongate (length/width ratio = 1.12–1.18). Eyes strongly convergent below (UOD/LOD ratio = 1.33–1.36). Clypeus 2/3 below suborbital tangent, apicolateral margins subparallel. Supraclypeal area longer than wide. Antennal sockets distant (IAD/OAD> 0.6). Frontal line carinate, ending 2.5 OD below median ocellus. Median ocellus above upper orbital tangent. Pedicel shorter than F1. F2 length 1.5X F1. F2–F10 elongate (length/width ratio = 1.60– 1.78). Metapostnotum relatively elongate (MMR ratio = 1.15–1.22), posterior margin rounded onto posterior surface.

Terminalia . S7 with median lobe acuminate ( Fig. 89 ). S8 with apicomedial margin weakly convex ( Fig. 89 ). Genital capsule as in Fig. 89 . Gonobase with ventral arms widely separated. Volsella roughly ovoid. Gonostylus small, dorsal setae elongate. Retrorse lobe relatively short, strongly attenuated apically.

Range. Maryland south to Florida, west to Texas ( Fig. 84 ). USA: FL, GA, LA, MD, MS, NC, SC, TX.

Additional specimens examined. USA: FLORIDA: 1Ƥ Highlands Co., Archbold Biological Station, N27.18833 W081.33778, 31.iii.2009 (J.S. Ascher, D. Webber), 1Ƥ Highlands Co., Archbold Biological Station, N27.18833 W081.33778, 31.iii.2009 (J.S. Ascher, H.G. Hall, D. Webber); [ AMNH]; 1Ƥ Everglades N.P., 23.iv.1961 (L.A. Kelton); [ CNC]; 1Ƥ Brighton, 10.iv.1937 (J.C. Bradley); 1Ƥ Inverness (C. Robertson); 1Ƥ Punta Gorda, 11.xi.11; 13 Alachua Co.; 1Ƥ Franklin Co., Carrabelle, 23.iii.1981 (L.L. Pechuman); [ CUIC]; 6ƤƤ ( Halictus ashmeadi paratypes) Inverness (C. Robertson); [ INHS]; 1Ƥ Collier Co., N26.1676 W081.0757, 27.i.2005 (S.W. Droege); 1Ƥ Martin Co., N27.0916 W080.1291, 4.vi.2007 (S.W. Droege); [ PCYU]; 1Ƥ Orange Co., Orlando, 4.iii.1992 (S.M. Fullerton); [ UCFC]; 1Ƥ Inverness (C. Robertson); [ UCMC]; GEORGIA: 1Ƥ Rabun Co., Rabun Bald, 4200 ft., 16.vii.1957 (J.G. Chilcott); [ CNC]; 1Ƥ Colquitt Co., Reed Bingham S.P., 23.v.1981 (G.C. Eickwort et al.); [ CUIC]; 5ƤƤ Liberty Co., St. Catherines I., N31˚40.9ʹ W081˚8.8ʹm 23–28.vi.1996 (A. Sharkov); [ PCYU]; LOUSIANA: 1Ƥ Sabine River Ferry, 20.vi.1917; [ CUIC]; MARYLAND: 1Ƥ Dorchester Co., N38.432 W076.1589, 21.viii.2003 (S.W. Droege); 1Ƥ Dorchester Co., N38.4597 W076.1394, 21.viii.2003 (S.W. Droege); 1Ƥ Somerset Co., N37.9938 W075.7305, 8.v.2002 (S.W. Droege); [ PCYU]; MISSISSIPPI: 3ƤƤ Jackson Co., N30.3802 W088.7383, 4–5.vi.2005 (S.W. Droege); 1Ƥ Jackson Co., N30.3992 W088.766, 4–5.vi.2005 (S.W. Droege); [ PCYU]; NORTH CAROLINA: 4ƤƤ Raleigh, 3.v.1951 (T.B. Mitchell); [ NCSU]; 2ƤƤ Dare Co., N35.8064 W075.7668, 7.vi.2005 (S.W. Droege); 1Ƥ13 Hyde Co., N35.4164 W076.1625, 7.vi.2005 (S.W. Droege); [ PCYU]; SOUTH CAROLINA: 6ƤƤ Dillon Co., Dillon, N34.41655 W079.37116, 34 m, 25.iv.1923; [ AMNH]; 2ƤƤ C. Sandhills NWR, N34.6072 W080.2183, 7.ix.2006 (S.W. Droege); [ PCYU]; TEXAS: 1Ƥ Tyler Co., N30.548 W094.409, 19.iv.2008 (J.L. Neff); [ CTMI].

Floral records. APIACEAE : Eryngium ; CLUSIACEAE : Hypericum ; ERICACEAE : Kalmia ; ONAGRACEAE : Oenothera ;; ROSACEAE : Photinia , Rubus .

DNA Barcode. Available. Multiple sequences.

Comments. Common.

Figures

FIGURE 84. Distribution map of Lasioglossum coreopsis (stars) and L. creberrimum (circles).

FIGURE 85. Lasioglossum creberrimum (Smith) female, (A) lateral habitus, (B) face. Scale bars = 1 mm.

FIGURE 86. Lasioglossum creberrimum (Smith) female, dorsal view of mesosoma.

FIGURE 87. Lasioglossum creberrimum (Smith) male, (A) lateral habitus, (B) face. Scale bars = 1 mm.

FIGURE 88. Lasioglossum creberrimum (Smith) male, dorsal view of mesosoma.

FIGURE 89. Lasioglossum creberrimum (Smith) male terminalia, (A) ventral view, (B) dorsal view. Scale bar = 0.5 mm.