Lasioglossum (Dialictus) callidum (Sandhouse)

Halictus (Chloralictus) callidus Sandhouse, 1924: 34 . 3.

Holotype. 3 USA, Virginia, East Falls Church, 20.vii, on Daucus carota (S.A. Rohwer); [NMNH: 26436]. Examined.

Taxonomy. Michener, 1951: Lasioglossum (Chloralictus) callidum, p. 1112 (catalogue); Mitchell, 1960: Dialictus callidus 3, p. 385, D. versatus Ƥ3 (misdet.), p. 428 (redescription); Krombein, 1967: Lasioglossum (Dialictus) callidum, p. 462 (catalogue); Hurd, 1979: Dialictus callidus, p. 1965 (catalogue); Moure & Hurd, 1987: Dialictus callidus, p. 94 (catalogue); Gibbs, 2010b: Lasioglossum (Dialictus) callidum Ƥ3, p. 84 (redescription, key).

Diagnosis. Female L. callidum can be recognised by the following diagnostic combination: mandible with strongly curved dorsal margin (Fig. 19 B), protrochanter wide (Fig. 18 B), and mesepisternum rugulose. They share the mandible and protrochanter characters with L. connexum (Cresson) but this species has the mesepisternum polished and distinctly punctate. Female L. callidum are similar to L. versatum and L. trigeminum, both of which lack the mandible and protrochanter characters.

Male L. callidum can be recognised by the following diagnostic combination: protrochanter wide (Fig. 34 B), mesepisternum rugulose, and metasomal terga with distinct punctures on the apical impressed areas. They are similar to L. connexum and L. versatum . The former species has the mesepisternum punctate and the latter species has the protrochanter narrow.

Range. Ontario south to Georgia, west to Colorado. USA: AL, CO, GA, MD, MO, MS, NE, NC, NY, SC, TN, VA, WI. CANADA: ON.

DNA Barcode. Available. Multiple sequences. DNA barcodes are identical to those of L. versatum .

Comments. Common.

Mitchell (1960) mistook this species in part for L. versatum (see Gibbs 2010b).