Retrieved from: Gibbs, J. 2010. Revision of the metallic species of Lasioglossum (Dialictus)in Canada (Hymenoptera, Halictidae, Halictini). Zootaxa; 2591, 80-84
Halictus brunneiventris Crawford, 1907: 194. ♀.
Holotype. ♀ USA, Nevada, Ormsby Co., vii (Baker); [NMNH: 12079]. Examined.
Halictus (Chloralictus) pilosicaudus Cockerell, 1937b: 155. ♀. [new synonymy]
Holotype. ♀ USA, California, San Miguel Island, end of vii, (Cockerell); [CAS: 4659].Examined.
Taxonomy. Michener, 1951: Lasioglossum (Chloralictus) brunneiventre, p. 1112, L. (C.) pilosicaudum, p.
1116 (catalogue); Hurd, 1979: Dialictus brunneiventris, p. 1964, D. pilosicaudus, p. 1970 (catalogue); Moure
& Hurd, 1987: Dialictus brunneiventris, p. 93, D. pilosicaudus, p. 123 (catalogue).
Diagnosis. Females of L. brunneiventre are recognisable by the diagnostic combination of a small size
(3.74.0 mm), elongate head (length/width ratio = 1.071.10), dense mesoscutal and mesepisternal punctures,
complete T1 acarinarial fan and a lack of dense tomentum on the brown metasomal terga. They are most similar
to L. macroprosopum (see below) which are larger (5.986.34 mm) with a slightly shorter head (length/
width ratio = 1.051.07). A similar undescribed species of intermediate size (approx. 4.25.2 mm) with a very
elongate head (length/width ratio = 1.101.17) occurs in the Western USA as far north as southeastern Washington
but has abundant tomentum on the metasomal terga.
Males of L. brunneiventre are similar to females but may be further distinguished by their weakly convergent
eyes (UOD/ LOD ratio = 1.28), relatively short flagellomeres (length/width ratio = 1.441.50), and less
dense mesoscutal punctures.
Redescription. FEMALE. Length 3.724.03 mm; head length 1.221.32 mm; head width 1.131.22 mm;
forewing length 2.752.87 mm.
Colouration. Head and mesosoma pale green to golden green, sometimes with blue reflections. Labrum
reddish brown to yellow. Mandible orange to yellow. Clypeus with apical half brown, distal margin reddish
brown to yellow, basal half, and supraclypeal area with brassy reflections. Antenna dark brown, flagellum
with ventral surface reddish brown to bright orange-yellow. Tegula pale yellow. Wing membrane subhyaline,
venation and pterostigma pale yellowish brown. Legs brown, tibial bases and apices, and tarsi reddish brown
to bright yellow, metabasitarsus infused with brown. Metasoma reddish brown, terga and sterna with apical
margins pale translucent brownish yellow.
Pubescence. White. Moderately dense. Head and mesosoma with moderately dense woolly hairs (11.5
OD), longest on genal beard, metanotum and mesopleuron (22.5 OD). Lower paraocular area and gena with
abundant tomentum partially obscuring surface. Propodeum with moderately dense plumose hairs on lateral
and posterior surfaces (22.5 OD). Metasomal terga with very dense, fine setae. T1 acarinarial fan complete,
mingling with erect hairs on lateral margins. T2T3 basolateral areas with tomentum. T4 disc with tomentum
partially obscuring surface. T2 apicolateral and T3T4 apical margins with weak, indistinct fringes.
Surface sculpture. Face imbricate, punctation fine and deep. Clypeus polished, basal margin imbricate,
punctation moderately sparse (i=13d). Supraclypeal area with punctation moderately sparse (i=12.5d).
Lower paraocular and antennocular areas with punctation dense (i≤d). Upper paraocular area, frons and ocellocular
area punctate-reticulate. Gena lineolate. Postgena polished. Mesoscutum polished, punctation fine and
deep, uniformly dense (i
Structure. Head elongate (length/width ratio = 1.071.10). Eyes convergent below (UOD/ LOD ratio =
1.101.20). Clypeus 1/2 below suborbital line, apicolateral margins 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 with 3 teeth. Metapostnotum moderately elongate (MMR ratio = 1.241.38). Propodeum with
oblique carina weak, lateral carina not reaching dorsal surface.
MALE. Similar to female except for the usual secondary sexual characters and as follows. Length. 3.90
mm; head length 1.32 mm; head width 1.20 mm; forewing length 2.87 mm.
Colouration. Flagellum with ventral surface yellow. Tibial bases and apices, and tarsi reddish brown.
Pubescence. Face below level of eye emargination with dense tomentum obscuring surface except clypeus
with moderately sparse tomentum, not obscuring surface
Surface sculpture. Mesoscutum punctation moderately sparse between parapsidal lines (i=12d). Propodeum
with dorsolateral slope and lateral and posterior surfaces reticulate-punctate.
Structure. Head elongate (length/width ratio = 1.10). Eyes convergent below (UOD/ LOD ratio = 1.28).
Antennal sockets distant (IAD/OAD > 1.0). Pedicel shorter than F1. F2 length 1.3X F1. F2F10 moderately
short (length/width ratio = 1.441.50). Metapostnotum moderately elongate (MMR ratio = 1.28), posterior
margin weakly angled onto posterior surface.
Terminalia. S7 with median lobe narrowly clavate, sides subparallel, apex rounded (Fig. 81D). S8 with
apicomedial margin weakly convex (Fig. 81D). Genitalia as in Fig. 81DE. Gonobase with ventral arms narrowly
separated. Gonostylus small, dorsal setae elongate. Retrorse lobes narrow, weakly attenuated apically.
Range. Southern British Columbia south to Southern California, east to Utah
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