Lasioglossum (Dialictus) versatum (Robertson)

Gibbs, Jason, 2011, Revision of the metallic Lasioglossum (Dialictus) of eastern North America (Hymenoptera: Halictidae: Halictini), Zootaxa 3073, pp. 1-216 : 206-207

Lasioglossum (Dialictus) versatum (Robertson)

Chloralictus versatus Robertson, 1902b: 249 . Ƥ 3.

Lectotype. Ƥ USA, Illinois, Macoupin Co., Carlinville, 8.iv.1886 (C. Robertson); [INHS: 543] by W. E. LaBerge (in Webb

1980). Examined.

Halictus subconnexus rohweri Ellis, 1915: 292 . Ƥ.

Lectotype. Ƥ USA, Virginia, Fairfax Co., Newington, 30.v.1911 (S.A. Rohwer) [UCMC] designated herein. Examined. Halictus (Chloralictus) apertus Sandhouse, 1924: 35 . 3.

Holotype. 3 USA, Virginia, Chain Bridge, 14.vi., (S.A. Rohwer); [ NMNH: 26437]. Examined. Halictus (Chloralictus) genuinus Sandhouse, 1924: 36 . 3.

Holotype. 3 USA, Virginia, Chain Bridge, 14.vi., (S.A. Rohwer); [ NMNH: 26438]. Examined. Halictus (Chloralictus) geminus Bohart, 1941: 138 . Lapsus calami .

Taxonomy. Viereck, 1916: Halictus (Chloralictus) versatus , p. 707 (key); Michener, 1951: Lasioglossum (Chloralictus) apertum , p. 1112, L. (C.) genuinum , p. 1113, L. (C.) rohweri , p. 1117, L. (C.) versatum , p. 1118 (catalogue); Mitchell, 1960: Dialictus apertus 3, p. 380, D. genuinus 3, p. 394, D. laevissimum 3 (misdet.), p. 401, L. rohweri Ƥ, p. 418 (redescription); Knerer and Atwood, 1962a: D. rohweri 3, p. 1230 (description); Krombein, 1967: Lasioglossum (Dialictus) rohweri , p. 466, L. (D.) versatum , p. 466, (catalogue); Dialictus apertus , p. 1964, D. genuinus , p. 1966, D. rohweri , p. 1971, D. versatus , p. 1972 (catalogue); Moure & Hurd, 1987: Dialictus apertus , p. 89, D. genuinus , p. 101, D. rohweri , p. 127, D. versatus , p. 137 (catalogue); Pesenko et al., 2000: Evylaeus rohweri , p. 52, E. versatus , p. 54 (review); Gibbs, 2010b: Lasioglossum (Dialictus) versatum Ƥ3, p. 342 (redescription, key, synonymy).

Diagnosis. Female L. versatum can be recognised by the following diagnostic combination: size large (5.1–6.8 mm); head wide (length/width ratio = 0.89–0.94); mandible with dorsal margin straight; clypeus 1/3–1/2 below suborbital line; mesoscutum tessellate, punctures moderately sparse punctures between parapsidal lines (i=1.5–3d), centre appearing flat; mesepisternum rugulose; tegula usually reddish brown; protrochanter unmodified; metapostnotum completely rugosocarinulate; T1 acarinarial fan with wide dorsal opening; and metasomal terga brown, apical impressed areas densely punctate. They are most similar to L. callidum , which has protrochanter very wide ( Fig. 18 B), mandible strongly curved at midlength of dorsal margin ( Fig. 19 B), and clypeus not much protruding below suborbital line.

Male L. versatum are similar to females but can be further recognised by the following combination: head round (length/width ratio = 1.00–1.01); face with dense tomentum; flagellomeres moderately long (length/width ratio = 1.43– 1.60), brownish yellow ventrally; metabasitarsus four times as long as broad; and apical impressed areas of metasomal terga punctate. Similar species include L. dubitatum , L. callidum , L. laevissimum and L. mitchelli . Male L. dubitatum have a short and wide metabasitarsus approximately three times as long as broad. Male L. callidum have wide protrochanter. Male L. laevissimum and L. mitchelli have apical impressed areas of metasomal terga impunctate.

Range. Quebec, south to North Carolina, west to Manitoba, Kansas (Fig. 231). USA: AR, CT, DE, IL, IN, KS, MA, MD, ME, MO, NC, NY, PA, TN, VA, WI. CANADA: MB, ON, PQ.

DNA Barcode. Available. Multiple sequences.

Comments. Common.

The lectotype of L. versatum does not match the species that was most commonly referred to by this name in the literature prior to Gibbs (2010b). Mitchell (1960) used this name (as Dialictus versatus ) to refer to what is here called L. callidum . The behavioural study of L. versatum by Michener (1966) apparently was at least in part a study of L. trigeminum (see above).

Despite the common use of the specific epithet rohweri in earlier literature, the location of the type series of Halictus subconnexus rohweri was not clear ( Moure & Hurd 1987; Gibbs 2010b). Ellis (1915) based her original description on two specimens from Newington, Virginia. A specimen with matching locality information to that given in the description, with a handwritten label by Ellis reading “ Halictus subconnexus rohweri Ellis ”, was found at UCMC. It is here designated as the lectotype to fix the commonly used epithet rohweri to a physical specimen and thus clarify the application of the name. A lectotype label has been affixed to the specimen. The identity of the lectotype agrees with common usage of the name.

Figures

FIGURE 18. Protrochanter (A) narrow, (B) wide (female L. callidum). (From Gibbs 2010 b).

FIGURE 19. Mandible of female (A) without strongly curved dorsal margin, (B) with strongly curved dorsal margin (L. callidum). (From Gibbs 2010 b).