Robertson 1892 : 270
Chloralictus obscurus
Halictus ( Chloralictus ) obscurus
Lasioglossum obscurum
Dialictus obscurus
Lasioglossum ( Dialictus ) obscurum
Dialictus obscurum
Dialictus obscurus
Lasioglossum ( Dialictus ) obscurum
Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini)
Gibbs, Jason
Zootaxa
2011
2011-10-28
3073
1
216
6P2DH
Robertson
Robertson
[151,738,1015,1041]
Insecta
Halictidae
Lasioglossum
Animalia
Hymenoptera
154
155
Arthropoda
species
obscurum
Dialictus
Halictus obscurus Robertson 1892: 270. Ƥ. Lectotype.Ƥ USA, Illinois, Macoupin Co., Carlinville, 8.v.1891(C. Robertson); [INHS: 10959] by W. E. LaBerge (in Webb 1980). Examined. Taxonomy. Robertson, 1902b: Chloralictus obscurus, p. 249 (key); Viereck 1916: Halictus( Chloralictus) obscurus, p. 707 (key); Michener, 1951: Lasioglossum obscurum, p. 1115 (catalogue); Mitchell, 1960: Dialictus obscurusƤ, p. 376 (redescription); Krombein, 1967: Lasioglossum( Dialictus) obscurum, p. 465, (catalogue); Hurd, 1979: Dialictus obscurum, p. 1969, (catalogue); Moure & Hurd, 1987: Dialictus obscurus, p. 117, (catalogue); Gibbs, 2010b: Lasioglossum( Dialictus) obscurumƤ3, p. 215 (redescription, key, synonymy).
Diagnosis.Female L. obscurumcan be recognised by the following diagnostic combination: mesoscutal punctures sparse throughout, mesepisternal punctures distinct ( Fig. 24A), propodeal carinae weak, and metasomal terga without tomentum but with very sparse apical fringes. They are superficially similar to L. nigrovirideand L. tenax. Female L. nigroviridehave moderately strong propodeal carinae and no fringe hairs on metasomal terga. Female L. tenaxhave dense punctures on the lateral portions of the mesoscutum. Male L. obscurumcan be recognised by the following diagnostic combination: head moderately elongate (length/ width ratio = 1.02–1.05); flagellomeres elongate (length/width ratio = 1.50–1.92); postgena imbricate; mesoscutum imbricate, punctures sparse (i=1–4d), denser laterad of parapsidal line (i=1–1.5d); mesepisternum punctate; apical impressed areas of metasomal terga impunctate; and S3–S5 apicolateral portions with sparse plumose hairs. They are similar to L. nigroviride, L. cattellae, L subversans, and L. tenax. Males of L. nigrovirideand L. subversanshave distinctly dense plumose hairs on the metasomal sterna. Male L. tenaxhave obscure mesepisternal punctures and the punctures of the metasomal terga limited to the basal portions and the premarginal lines. Male L. cattellaeare small ( 4.3–4.5 mm), with coarse mesoscutal and mesepisternal punctures, and distinctly lineolate postgena. Range.Ontario, south to North Carolina, west to Wisconsin. USA: CT, GA, IL, MD, MN, MI, MO, NC, NH, NY, OH, PA, TN, VT, WI, WV. CANADA: ON. DNA Barcode.Available. Multiple sequences.
Comments.Common.