Lasioglossum Curtis, 1833

Murao, Ryuki, Tadauchi, Osamu & Lee, Heung-Sik, 2015, Synopsis of Lasioglossum (Dialictus) Robertson, 1902 (Hymenoptera, Apoidea, Halictidae) in Japan, the Korean Peninsula and Taiwan, European Journal of Taxonomy 137, pp. 1-50 : 5-7

Genus Lasioglossum Curtis, 1833

Lasioglossum (Dialictus) Robertson, 1902 .

Paralictus Robertson, 1901: 229 . Type species: Halictus cephalicus Robertson, 1892 (preoccupied by Morawitz 1873 = Halictus cephalotes Dalla Torre, 1896 ), by original designation.

Dialictus Robertson, 1902: 48. Type species: Halictus anomalus Robertson, 1892 , by original designation and monotypy.

Chloralictus Robertson, 1902: 248. Type species: Halictus cressonii Robertson, 1890 , by original designation.

Halictus (Gastrolictus) Ducke, 1902: 102 . Type species: Halictus osmioides Ducke, 1902 , by monotypy.

Halictomorpha Schrottky, 1911: 81 . Type species: Halictomorpha phaedra Schrottky, 1911 , by original designation.

Rhynchalictus Moure, 1947: 5 . Type species: Rhynchalictus rostratus Moure, 1947 , by original designation.

Halictus (Smeathhalictus) Warncke, 1975: 88 . Type species: Melitta smeathmanella Kirby, 1802 , by original designation.

Habralictellus Moure & Hard, 1982: 46 . Type species: Halictus auratus Ashmead, 1900 , by original designation.

Lasioglossum (Afrodialictus) Pauly, 1984: 142 . Type species: Halictus bellulus Vachal, 1909 , by original designation.

Evylaeus (Viridihalictus) Pesenko, 2007a: 26 . Type species: Halictus viridis Brullé, 1840 , by original designation.

Evylaeus (Glauchalictus) Pesenko, 2007a: 26 . Type species: Halictus problematicus Blüthgen, 1923 , by original designation.

Evylaeus (Virenshalictus) Pesenko, 2007a: 26 . Type species: Halictus virens Erichson, 1835 , by original designation.

Evylaeus (Loethalictus) Pesenko, 2007a: 26 . Type species: Halictus loetus Brullé, 1840 , by original designation.

Evylaeus (Aerathalictus) Pesenko, 2007a: 27 . Type species: Melitta aerata Kirby, 1802 , by original designation.

Diagnosis

This subgenus is usually separated from the other subgenera of Lasioglossum occurring in eastern Asia by having a combination of the head and mesosoma with brilliant or dull green-metallic luster in both sexes and the female fore wing with a weak second submarginal vein. In eastern Asia, the female of the apristum group belonging to L. ( Sphecodogastra ) (corresponding to the carinate L. ( Evylaeus ) in the dissenting classification ( Ebmer 2002; Pesenko 2007a, as the genus Evylaeus )) has the same character states as L. (Dialictus). However, the members of this group can easily be separated from L. (Dialictus) in having the mesepisternum coarse reticulate-rugulose, the posterior surface of the propodeum with strong complete carina, and the inner hind tibial spur finely serrate.

Comments

As stated above, the green L. ( Evylaeus ) used by most Palaearctic researchers corresponds to L. (Dialictus) in the recent classification. Pesenko (2007a) re-classified Evylaeus sensu lato into 29 subgenera for the Palaearctic Region. In his systematic study, 6 of the subgenera ( Aerathalictus Pesenko , Glauchalictus Pesenko , Loethalictus Pesenko, 2007, Smeathhalictus Warncke, 1975, Viridihalictus Pesenko, 2007 and Virenshalictus Pesenko, 2007) correspond to L. (Dialictus) as shown above in the synonymy list (synonymies by Gibbs 2010). These subgenera sensu Pesenko (2007a) are treated as a species group in this paper.

The leucopus group

Species included in eastern Asia:

L. aeratum (Kirby, 1802)

L. algirum (Blüthgen, 1923)

L. angaricum (Cockerell, 1937)

L. leucopus (Kirby, 1802)

L. meakanense Murao & Tadauchi, 2009

L. pseudannulipes (Blüthgen, 1925)

L. viridellum (Cockerell, 1931)

Among the members of this group, both L. meakanense and L. pseudannulipes are known from Japan, and L. viridellum from the Korean Peninsula.

Diagnosis

Species of the leucopus group may be strictly characterized by a combination of the following character states: 1) male F2 short, approximately 1.2–1.5 × as long as F1; 2) mesepisternum reticulate-punctate on lower area in both sexes ( Fig. 1E ); 3) male metasomal sterna not modified (apical margin straight); 4) ventral retrorse lobe of male genitalia with moderately long setae only apically and distinct lineolation on surface ( Fig. 2D , F–I).

The diagnostic characters of this group are also shown in Ebmer & Sakagami (1990, as the leucopus group) and Pesenko (2007a, as subgenus Aerathalictus Pesenko, 2007 ).

Distribution

Palaearctic to northern Oriental Region.

Comments

This group is assumed to be monophyletic, based on the ventral retrorse lobe of male genitalia with moderately long setae only apically and the distinct lineolation on the surface. This character state may be unique within the subgenus. A comprehensive comparative study of the ventral retrorse lobe has not been performed for the subgenus, but this state may be an autapomorphy for the leucopus group.

Figures

Fig. 1. A–E. Lasioglossum (Dialictus) viridellum (Cockerell, 1931). A–B. Head in frontal view. C–D. Labrum. E. Mesepisternum. A, C. ♀. B, D–E. ♂.

Fig. 2. — A–E. Lasioglossum (Dialictus) viridellum (Cockerell, 1931), ♂. — F. L. (D.) aeratum (Kirby, 1802), ♂. — G. L. (D.) aligrum (Blüthgen, 1923), ♂. — H. L. (D.) annulipes (Morawitz, 1876), ♂. — I. L. (D.) leucopus (Kirby, 1802), ♂. A. Genitalia in ventral view. B. Genitalia in dorsal view. C. Genitalia in lateral view. D, F–I. Ventral retrorse lobe of genitalia. E. S7–S8. Scale bars: A–C, E = 0.2 mm, D, F–I = 0.1 mm.