Retrieved from: Gibbs, J. 2010. Revision of the metallic species of Lasioglossum (Dialictus)in Canada (Hymenoptera, Halictidae, Halictini). Zootaxa; 2591, 153-156
Holotype. ♀ CANADA, British Columbia, Okanagan-Similkameen Reg. Dist., Osoyoos, Mt. Kruger, Strawberry Crk.
Rd., N-site, N49.0421 W119.5114, 505 m, 16.vii.2008 (L.R. Best); [PCYU: LRB-2325].
Diagnosis. Females of L. imbrex, L. ellisiae and L. tegulare may be easily distinguished from other Canadian
Dialictus by their large, distinctly punctate tegula with an acute posterior angle (Fig. 7A). Females of L. ellisiae
and L. imbrex both have the mesepisternum smooth between punctures, with at most weak lines on the
interspaces. Female L. imbrex have denser tomentum on the basal portions of T2T3 and across the disc of T4
(Fig. 123D) than does L. ellisiae. Female L. tegulare have the mesepisternum between punctures dull due to
Description. FEMALE. Length 4.515.12 mm; head length 1.241.31 mm; head width 1.261.38 mm;
forewing length. 3.053.17 mm.
Colouration. Head and mesosoma dull metallic pale green with some golden and bluish reflections.
Labrum sometimes reddish brown. Mandible orange. Clypeus with apical blackish brown and basal half, and
supraclypeal area brassy. Antenna dark brown, with ventral surface brownish yellow. Tegula brown to black,
central area reddish. Wing membrane subhyaline, venation and pterostigma pale yellowish brown. Legs dark
brown, promedio- and prodistitarsi reddish, meso- and metadistitarsi reddish brown. Propodeum sometimes
bluish. Metasoma dark brown, terga and sterna with apical margins reddish to translucent brownish yellow.
Pubescence. Dull white. Moderately dense. Head and mesosoma with moderately dense woolly hairs (1
1.5 OD), longest on genal beard, metanotum and mesopleuron (22.5 OD). Lower paraocular and gena with
moderately dense tomentum, partially obscuring surface. Propodeum with moderately dense plumose hairs on
lateral and posterior surfaces (22.5 OD). Metasoma terga with moderately sparse, fine setae. T1 acarinarial
fan complete. T3T5 ventrolateral reflexed areas with few, erect hairs (2.53 OD). T2 basolaterally, T3
basally and laterally, and T4 entirely with moderately dense tomentum, partially obscuring surface. T2 apicolateral
and T3T4 apical margins with sparse fringes.
Surface sculpture. Face weakly imbricate, punctation moderately strong. Clypeus polished basal margin
imbricate, punctation moderately dense (i=12d). Supraclypeal area with punctation moderately sparse (i=1
2.5d). Lower paraocular area punctation dense (i
Structure. Head wide (length/width ratio = 0.950.98). Eyes convergent below (UOD/LOD ratio = 1.14
1.19). Clypeus 1/22/3 below suborbital tangent, apicolateral margins convergent. Antennal sockets close
(IAD/OAD < 0.5). Frontal line carinate, ending 2.5 OD below median ocellus. Gena narrower than eye. Tegula
elongate with posterior margin angled posteromedially. Inner metatibial spur pectinate with 23 teeth.
Metapostnotum moderately elongate (MMR ratio = 1.161.32), posterior margin weakly angled onto posterior
surface. Propodeum with oblique carina weak, lateral carina weak not reaching dorsal margin.
Range. Alberta, British Columbia south to southern California (Fig. 124).
Paratypes. CANADA: ALBERTA: 2♀♀ Writing-On-Stone P.P, 14.iv.1984 (A.T. Finnamore); 1♀ Writing-
On-Stone P.P., 14.vi.1984 (T. Spanton); 1♀ Writing-On-Stone P.P, 1726.iv.1990, sage-north, (D.
McCorquodale); 1♀ Writing-On-Stone P.P, 26.v6.vi.1990, grass-south, (D. McCorquodale); 2♀♀ Writing-
On-Stone P.P, 1220.vi.1990, sedge-south, (D. McCorquodale); 1♀ Writing-On-Stone P.P, 1.viii.1990, (M.
Klassen); [PMAE]; USA: CALIFORNIA: 1♀ Los Angeles Co., N34.1116 W118.7773, 30.v.2008 (S.W.
Droege); 1♀ Mariposa Co., Forest Rd., 1.1 mi S Eagle Pk., 11S N4173170 E253922, 576 m, 24.v.2005 (L.
Fuerst, J. Gibbs & E. Stephens); 1♀ Tueeulala Falls, 11S N4173170 E253922, 1225 m, 26.vii.2005 (E. Stephens);
1♀ Tueeulala Falls, 11S N4173170 E253922, 1225 m, 26.vii.2005 (H. Briggs & E. Stephens);
[BBSL]; 1♀ Santa Monica Mtns., N34.0464 W118.8976, 1.vi.2008 (S.W. Droege); 1♀ Santa Monica Mtns.,
N34.1419 W118.7767, 30.v.2008 (S.W. Droege); [PCYU]; 1♀ Tuolumne Co., Poopenaut Vly., 1.2 mi SWbyS
Dam, 11S N4202202 E253883, 1060 m, 30.vi.2005 (L. Fuerst); OREGON: 1♀ Farewell Bend S.P.,
N44.30962 W117.22057, 659 m, 27.vi.2007 (Gibbs & Sheffield); [PCYU].
Etymology. The specific epithet refers to a type of roof tile used in conjunction with another tile called a
tegula in Ancient Greek and Roman architecture.
Floral records. ASCLEPIADACEAE: Asclepias, ASTERACEAE: Achillea millefolium.
Comments. Uncommon in Canada. This species belongs to the L. tegulare species-group. Specimens of
the L. tegulare group in the western USA have most often been identified as L. tegulariforme (Crawford),
originally described from Nevada. The holotype of L. tegulariforme has an unusually long and acute posterior
projection on the tegula that distinguishes it from other species in the L. tegulare group. DNA barcodes from
L. tegulariforme individuals collected in Nevada are clearly different from DNA barcodes of L. imbrex. It is
likely that the name L. tegulariforme has been too widely applied and many Western specimens actually
belong to L. imbrex.