Retrieved from: Gibbs, J. 2010. Revision of the metallic species of Lasioglossum (Dialictus)in Canada (Hymenoptera, Halictidae, Halictini). Zootaxa; 2591, 114-116
Dialictus dubitalus Mitchell, 1960: 436. ♂. lapsus calami (spelled D. dubitatus in key, p. 376 and index, p. 533)
Holotype. ♂ USA, New York, McLean Bogs, Cortland Co., June 20.vi.1936 [CUIC: 4890]. Examined.
Taxonomy. Krombein, 1967: Lasioglossum (Dialictus) dubitatum, p. 463 (catalogue); Hurd, 1979: Dialictus
dubitatus, p. 1966 (catalogue); Moure & Hurd, 1987: Dialictus dubitatum, p. 100 (catalogue).
Diagnosis. Male L. dubitatum are recognisable by their short and wide hind basitarsus which is approximately
three times as long as broad (Fig. 100D). Other species have the hind basitarsus four times as long as
broad. Otherwise this species is most similar to L. versatum which is virtually identical in all respects except
this species has a long and narrow hind basitarsus approximately four times as long as broad. See diagnosis
for L. versatum.
FEMALE. Unknown.
MALE. Length. 5.00 mm; head length 1.49 mm; head width 1.48 mm; forewing length 3.84 mm.
Colouration. Head and mesosoma bluish green. Mandible orange. Clypeus with apical half reddish
brown. Antenna dark brown, flagellum with ventral surface yellowish orange. Tegula dark reddish brown.Wing membrane subhyaline, venation and pterostigma brownish yellow. Legs brown, tibial apices and bases
and tarsi reddish brown. Metasoma dark brown, terga and sterna with apical margins reddish brown to translucent
brownish yellow.
Pubescence. Dull white. Moderately sparse. Head and mesosoma with moderately sparse woolly hairs (1–
1.5 OD), longest on genal beard, metanotum and mesopleuron (1.5–2 OD). Face below eye emargination with
sparse tomentum not obscuring surface except lower paraocular and antennocular areas with moderately
dense tomentum, partially obscuring surface. Gena with sparse tomentum. Propodeum with moderately sparse
plumose hairs on lateral and posterior surfaces (1.5–2 OD). Metasomal terga with sparse, fine setae. T2–T3
basolaterally with very small patches of tomentum. S3 apicolateral and S4–S5 lateral portions with moderately
dense plumose hairs.
Surface sculpture. Face imbricate, punctation fine, shallow. Clypeus with apical half polished, punctation
moderately dense (i=1–1.5d). Supraclypeal area with punctation moderately sparse (i=1–2.5d). Lower paraocular
area punctation dense (i≤d). Antennocular area punctation moderately dense (i=1–1.5d). Upper paraocular
area and frons punctate-reticulate. Ocellocular area punctate (i=d). Gena weakly lineolate. Postgena
imbricate. Mesoscutum tessellate-imbricate, punctation fine, shallow, sparse between parapsidal lines (i=1–
3d), dense laterad of parapsidal line (i=d), rugulose-punctate on anterolateral portion. Mesoscutellum apparently
similar to mesoscutum [mostly obscured by pin]. Axilla minutely punctate. Metanotum rugulose.
Preëpisternum rugose. Hypoepimeral area rugulose. Mesepisternum rugose. Metepisternum with dorsal half
weakly rugose, ventral half imbricate. Metapostnotum completely rugoso-striate. Propodeum with dorsolateral
slope and lateral and posterior surfaces rugose. Metasomal terga polished, punctation on basal halves
moderately dense (i=1.5d), sparse on apical half, including apical impressed areas (i=2–3d).
Structure. Head relatively elongate (length/width ratio = 1.01). Eyes strongly convergent below (UOD /
LOD ratio = 1.54). Clypeus 2/3 below suborbital line, anterolateral margins weakly convergent. Antennal
sockets distant (IAD/OAD > 1.4). Frontal line carinate, ending 2 OD below median ocellus. Pedicel shorter
than F1. F2 length 1.7X F1. F2–F10 moderately elongate (length/width ratio = 1.43–1.64). Gena narrower
than eye. Metabasitarsus short and broad, 3 times as long as broad. Metapostnotum truncate, posterior margin
angled. Propodeum with oblique carina virtually absent, lateral carina moderately strong, reaching 2/3 of the
distance to dorsal margin.
Terminalia. S7 median lobe clavate, apex rounded (Fig. 100E). S8 posterior margin weakly convex (Fig.
100E). Genitalia as in Fig. 100E. Gonobase with ventral arms widely separated. Gonostylus small, dorsal
setae elongate. Retrorse lobe narrow, attenuated apically.
Range. New York, possibly Ontario and Quebec (Fig. 99).
Comments. Rare. Lasioglossum dubitatum is nearly identical to the commonly collected L. versatum
except for the shape of the metabasitarsus. Additional material is needed to determine the relationship of these
two species for which DNA barcoding may assist. The Canadian records cannot be confirmed but the species
is included due to the proximity of the type locality to Ontario.
Extracted from Jason Gibbs. 2011. Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini.) Zootaxa.
Lasioglossum (Dialictus) dubitatum (Mitchell)
Dialictus dubitalus Mitchell, 1960: 436. ♂. Lapsus calami (spelled D. dubitatus in key, p. 376 and index, p. 533)
Holotype. ♂ USA, New York, McLean Bogs, Cortland Co., June 20.vi.1936 [CUIC: 4890]. Examined.
Taxonomy. Krombein, 1967: Lasioglossum (Dialictus) dubitatum, p. 463 (catalogue); Hurd, 1979: Dialictus dubitatus, p.
1966 (catalogue); Moure & Hurd, 1987: Dialictus dubitatum, p. 100 (catalogue); Gibbs, 2010b: Lasioglossum (Dialictus)
dubitatum ♂, p. 114 (redescription, key).
Diagnosis. Male L. dubitatum are unique in having metabasitarsus short measuring only about three times as long as
broad (Fig. 33B). In other respects male L. dubitatum match closely male L. versatum (see diagnosis below).
Female unknown.
Range. New York, possibly Ontario, Quebec (Moure & Hurd 1987).
DNA Barcode. Unavailable.
Comments. Rare. Only the holotype is known, although records exist for Ontario and Quebec. The type locality is a
bog, which is a habitat infrequently visited by melittologists.
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