Lasioglossum (Dialictus) tamiamense (Mitchell)

Gibbs, Jason, 2011, Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini), Zootaxa 3073, pp. 1-216 : 188-191

Lasioglossum (Dialictus) tamiamense (Mitchell)

( Figures 204–206 )

Dialictus tamiamensis Mitchell, 1960: 421 . Ƥ 3.

Holotype. Ƥ USA, Florida, Olga, 29.iii.1954, on sand flats (K.V. Krombein); [ NMNH: 66070]. Examined.

Taxonomy. Krombein, 1967: Lasioglossum (Dialictus) tamiamense , p. 466 (catalogue); Moure and Hurd, 1987: Dialictus tamiamensis , p. 133 (catalogue).

Diagnosis. Female L. tamiamense can be recognised by the following diagnostic combination: head long (length/ width ratio = 1.08–1.09) ( Fig. 204 B); mesoscutal punctures dense, except along medial line ( Fig. 205 ); metapostnotal rugae very fine, obscure among tessellate background ( Fig. 205 ); T1 acarinarial fan large, complete ( Fig. 205 ), intermixed with erect hairs dorsally; and T2 apical impressed area with distinct but fine punctation. They are most similar to L. halophitum and L. creberrimum . Female L. halophitum have mesoscutal punctures sparse over most of disc only becoming dense adjacent to the parapsidal lines ( Fig. 122 ). Female L. creberrimum have T1 acarinarial fan smaller without intermixed erect hairs dorsally, and T2 apical impressed area with very obscure punctation.

Male L. tamiamense can be recognised by the following diagnostic combination: head long (length/width ratio = 1.07) ( Fig. 206 B), clypeus with distal margin brownish yellow ( Fig. 206 B), mesoscutal punctures contiguous (i<d), T1– T2 apical impressed areas impunctate, and S5 apical margin deeply concave with dense apicolateral hairs. They are most similar to male L. creberrimum , which have T1–T2 at most narrowly impunctate at apical margin and S5 apical margin weakly concave with sparse apicolateral hairs.

Redescription. FEMALE. Length 4.60–5.02 mm; head length 1.52–1.54 mm; head width 1.40–1.42 mm; forewing length 3.39–3.45 mm.

Colouration. Head and mesosoma blue with greenish reflections. Clypeus with apical half blackish brown. Supraclypeal area bronze. Antenna dark brown, flagellum with ventral surface reddish brown. Tegula brownish yellow. Wings faintly dusky, venation and pterostigma brownish yellow. Legs brown, except medio- and distitarsi reddish brown. Metasomal terga and sterna brown, apical margins translucent brownish 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. T2–T5 lateral portions with sparse tomentum. T2 apicolateral and T3–T4 apical margins with sparse fringes.

Surface sculpture. Face imbricate, punctation fine. Clypeus punctation dense (i≤d). Supraclypeal area with punctation moderately dense (i≤d). 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 fine, 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<d). Axilla punctate. Metanotum imbricate. Preëpisternum rugose. Hypoepimeral area imbricate. 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 imbricate-tessellate, posterior surface tessellate. Metasomal terga polished, punctation moderately dense throughout (i=1–1.5d), sparser on apical impressed areas (i=1–2.5d).

Structure. Head elongate (length/width ratio = 1.08–1.09). Eyes convergent below (UOD/LOD ratio = 1.23–1.26). Clypeus ½ below suborbital tangent, apicolateral margins weakly convergent. Antennal sockets close (IAD/OAD <0.5). Frontal line carinate, ending 2.5 OD below median ocellus. Gena narrower than eye. Inner metatibial spur pectinate with 3–4 branches. Metapostnotum truncate (MMR ratio = 1.30–1.35), posterior margin narrowly rounded onto posterior surface. Propodeum with oblique carina fine, lateral carina weak, reaching halfway to dorsal margin.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length 3.81 mm; head length 1.39 mm; head width 1.30 mm; forewing length 2.96 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 brownish yellow.

Pubescence. Paraocular area below eye emargination with tomentum obscuring surface. Clypeus largely obscured by tomentum. S2–S3 with posteriorly directed hairs (1–1.5 OD), S4–S5 apical margins with dense hairs.

Surface sculpture. Mesoscutellar punctation dense (i<d). Metasomal terga with apical impressed areas impunctate.

Structure. Head elongate (length/width ratio = 1.07). Eyes strongly convergent below (UOD/LOD ratio = 1.38). Clypeus 2/3 below suborbital tangent, apicolateral margins subparallel. Antennal sockets distant (IAD/OAD> 0.7). Frontal line carinate, ending 2 OD below median ocellus. Pedicel shorter than F1. F2 length 1.8X F1. F2–F10 moderately elongate (length/width ratio = 1.50–1.60). Metapostnotum elongate (MMR ratio = 1.28), posterior margin rounded onto posterior surface. S5 deeply concave.

Terminalia . S7 with median lobe acuminate. S8 with apicomedial margin weakly convex. Gonobase with ventral arms separated. Volsella roughly ovoid. Gonostylus long, dorsal setae elongate. Retrorse lobe elongate, attenuated apically.

Range. Florida ( Fig. 199 ).

Additional material examined. USA: FLORIDA: 1Ƥ Highlands Co., Archbold Biological Station, N27.18833 W081.33778, 18.iii.2002 (J.S. Ascher); 13 Putnam Co., Crescent City, N29.43 W081.5108, 20.iv.1908 (Van Duzee); [ AMNH];; 1Ƥ paratype Punta Gorda, 11.iv.1962 (J.R. Vockeroth); [ CNC]; 2ƤƤ paratypes East end Tamiami Trail, 22.vi.1949 (T.B. Mitchell); 6ƤƤ paratype Marion Co., 8.iv.1956 (R.A. Morse); 13 Punta Gorda, 17.xi.1911; 1Ƥ Highlands Co., Archbold Bio. Res. Stn., 14.iv.1963 (J.G. & B.L. Rozen); 13 Highlands Co., Highland Hammock S.P., 13.iv.1974 (G.C. Eickwort); 1Ƥ Alachua Co., 13.ii.1930 (C.J. Guard); 13 Columbia Co., 22.i.1930 (R.B. Howard); 1Ƥ Orange Co., 7–15.ii.1930 (W.M. Loe)); 1Ƥ Volusia Co., 29.i.1930 (W.A. Hiers); 1Ƥ Union, Walton Co., 23.xii.1929 (R.B. Howard); [ CUIC]; 1Ƥ ( Halictus ashmeadi paratype) Inverness (C. Robertson); [ INHS]; 4ƤƤ paratypes East end Tamiami Trail, 22.vi.1949 (T.B. Mitchell); 4ƤƤ paratypes Marion Co., 6.iv.1956 (R.A. Morse); 2ƤƤ paratypes Marion Co., 17.iv.1956 (R.A. Morse); 1Ƥ paratype Olga, 29.iii.1954 (K.V. Krombein); 13 paratype Olga, 30.iii.1954 (K.V. Krombein); 2ƤƤ paratypes Volusia Co., 10.viii.1936 (H.A. Denmark); [ NCSU]; 13 paratype Olga, on sand flats, 30.iii.1954 (K.V. Krombein); [ NMNH].

Floral records. ASTERACEAE : Bidens pilosa , Erigeron quercifolius ; FABACEAE : Chamaecrista fasciculata , Medicago “lupina”, Melilotus officinalis , Trifolium repens ; HYDROPHYLLACEAE : Hydrolea ovata ; LAMIACEAE : Stachys floridana .

DNA Barcode. Available. Single sequence.

Comments. Uncommon.

Several paratypes of L. tamiamense are in fact L. creberrimum (one paratype from Alachua county is a L. puteulanum ).

Figures

FIGURE 122. Lasioglossum halophitum (Graenicher) female, dorsal view of mesosoma.

FIGURE 199. Distribution map of Lasioglossum stuartense (square), L. surianae (stars) and L. tamiamense (circles).

FIGURE 204. Lasioglossum tamiamense (Mitchell) female, (A) lateral habitus, (B) face. Scale bars = 1 mm.

FIGURE 205. Lasioglossum tamiamense (Mitchell) female, dorsal view of mesosoma.

FIGURE 206. Lasioglossum tamiamense (Mitchell) male, (A) lateral habitus, (B) face. Scale bars = 1 mm.