Dufourea fimbriata (Cresson, 1878)

Dufourea fimbriata Female

Dufourea fimbriata Male

Panurgus fimbriatus Cresson, 1878: 63 (♀ description).

Halictoides harveyi Cockerell, 1906: 223 (♀ description).

Halictoides harveyi sierrae Michener, 1937: 397 (♀ description).

Diagnosis.The main diagnostic characters of this species are the rugosostriate propodeal triangle and the nearly opaque apical impressed areas of the terga. Those observed only in the male: the simple and slender hind legs, S3-S5 with lateral depressions, S5 with concave margin. This species is similar to D. marginata and D. trochantera in its small size and wide head, however these two species tend to be larger in size and have rather strongly hyaline apical impressed areas of the terga.

FEMALE: Length 6 mm.

Head:

Dufourea fimbriata female head

1) head much broader than long, 1.24:1; compound eyes subparallel; OVD = 1.5MOD, OOD = 2.3MOD, IOD = 2.3MOD. 2) supraclypeal area protuberant in lateral view with elevated vertical midline between antennae; clypeus entirely shiny, strongly protuberant, considerably broader than long, twice as broad as long; labrum slightly triangular, broader than long, mandibles fitting beneath the large labral process when closed. 3) mandible bi-dentate. 4) genal area somewhat narrower than compound eyes, becoming very narrow below. 5) pubescence rather short, quite thin and inconspicuous, pale in general, but some dark brown-black hairs on face; pale hairs present on vertexal area, scape, postgenal area, and below apical clypeal margin, dark hairs present on genal area, area between vertexal area and antennae, and area between compound eyes and antennae. 6) punctures deep, distinct, close and rather fine on upper part of face below ocelli (<2pd), becoming very sparse on paraocular area, where the surface is shiny (>3pd); very fine and close on the markedly convex supraclypeal area, becoming very dense laterally, somewhat sparse centrally; coarse, deep and well separated over most of clypeus, more dense near basal margin (1-2pd); punctures minute and slightly separated over most of vertexal area, becoming somewhat closer and more obscure on upper part of genal area; with impunctate shiny areas along outer margin of lateral ocelli. 7) IAD subequal to AOD, antennal socket separated from upper margin of clypeus by its diameter; antennae quite short, flagellar segments considerably broader than long, breadth increasing apically.

Mesosoma:

8) pubescence largely pale and short, hairs thin and sparse, longest on mesopleuron and lateral mesoscutellum; mesoscutum with disc nearly bare posteriorly. 9) mesoscutum shiny, punctures fine, well separated in general (>2pd), becoming slightly sparse in center of disc posteriorly (>4pd), dense at extreme sides but not crowded even between notaulice and tegula; mesoscutellum shiny, very faintly impressed medially, punctures sparse, becoming more dense apically (<1pd); mesopleuron shiny, punctures fine and close (1-2pd), hypoepimeral area mostly shiny, posteriorly imbricate, with punctures evenly distributed throughout (2-3pd); propodeal triangle subequal in length to mesoscutellum, shiny and rugosostriate; lateral and posterior propodeal surface dull and imbricate, punctures somewhat obscure, separated by 2-4pd anteriorly, posteriorly impunctate. 10) legs dark brown; spurs, especially the mid and hind pair, very long and slender, yellowish, mid tibial spur about 3/4 as long as mid basitarsus; scopal hairs white and fine. 11) tegula dark brown in large part, becoming somewhat yellowish-hyaline along margin, with pale hairs on anterior half. 12) wings lightly infuscated, veins and stigma more brownish-red, 1st recurrent vein entering 2nd submarginal cell about half as far from base than distance of 2nd recurrent vein to apex.

Metasoma:

13) T1-T3 quite smooth and shiny, with minute and rather close punctures basally (2-3pd), well separated throughout most of tergum (>4pd), T4-T5 with somewhat coarser and rather close, evenly distributed punctures (2-3pd), apical impressed areas smooth and impunctate, more or less yellowish, discal pubescence very short and obscure, suberect, pale, becoming somewhat dark brown-black on the more apical terga. 14) sterna with pale, erect apical pubescence; S1 with sparse pubescence basally, S2-S5 with long, pale pubescence apically and short to bare centrally.

MALE: Length 5.5 mm.

Head:

Dufourea fimbriata male head

1) head much broader than long, 1.22:1; compound eyes slightly convergent below; OVD = 1.5MOD, OOD = 2.5MOD, IOD = 2.3MOD. 2) supraclypeal area slightly protuberant in lateral view, with elevated vertical midline; clypeus strongly protuberant, broader than long; labrum broader than long, entirely exposed by the closed mandibles. 3) mandible bi-dentate. 4) genal area narrower than compound eyes, very much narrowed below. 5) pubescence entirely pale, whitish on face, densely covering supraclypeal area and clypeus, obscuring surface beneath, long pale pubescence around scape. 6) punctures of vertexal area fine, somewhat more separated medially than on face (2-3pd), becoming well separated on each side; genal area above closely and rather obscurely punctate, the lower part becoming shiny and impunctate; punctures below ocelli fine and dense (<1.5pd), becoming much more coarse and relatively sparse toward antennae on each side (2-4pd), the strongly convex supraclypeal area densely pubescent, with close punctures (1-3pd), largely hidden beneath the pubescence, clypeus with shallow and rather close punctures beneath the dense pubescence. 7) IAD subequal to AOD, antennal socket separated from margin of clypeus by slightly more than its diameter; F1 about as broad as long, slightly longer than pedicel and half as long as F2, F2 twice as long as broad, median and apical segments longer than broad, not quite as long as F2; F5-F11 with basal depression.

Mesosoma:

8) pubescence largely whitish, longest on mesopleuron; mesoscutum and mesoscutellum with sparse, thin, whitish pubescence, legs, especially hind, with long white pubescence. 9) mesoscutum and mesoscutellum shiny, very finely and somewhat irregularly punctate, punctures somewhat separated in center of discs (>3pd), becoming closer, but not crowded, at extreme sides (<2pd); mesopleuron smooth, shiny, punctures well separated (>4pd) becoming minute and dense posteriorly (1-2pd); hypoepimeral area smooth and shiny, punctures dense above (1pd) but becoming sparse below (3-4pd); propodeal triangle 2/3 as long as mesoscutellum, shiny and rugosostriate; lateral propodeal surface imbricate, densely punctate anteriorly (1-2pd), punctures becoming obscure posteriorly (2-4pd), posterior propodeal surface imbricate and rough, punctures somewhat obscure (3-4pd). 10) legs black; hind femur relatively slender but somewhat curved, lower surface flattened and smooth; hind tibia slender basally, mid tibial spur about 1/3 as long as mid basitarsus; hind basitarsus slender, parallel-sided, about 4 times as long as broad, much shorter than tibia. 11) tegula brownish and shiny, anterior half densely punctate, posterior half impunctate, dark erect hairs on disc, pale hairs anterolaterally. 12) wings lightly infuscated, veins and stigma brownish-red; 1st recurrent vein entering 2nd submarginal cell about half as far from base than distance of 2nd recurrent vein to apex.

Metasoma:

13) terga shiny, minutely punctate, punctures more dense basally (2-3pd) becoming sparse apically (>4pd); apical impressed areas entirely impunctate, more or less hyaline yellow, discal pubescence suberect, thin and obscure, largely pale on the more basal terga, becoming more erect, conspicuous and dark brown-black on the more apical terga (T5 and T6). 14) S3-S5 with lateral depressions, sometimes elevated or carinate, S5 with apical margin concave, S6 with a median apical process with an elevated lobe on each side.

Genitalia: Dorsal view Ventral view

Dufourea fimbriata genitalia, dorsal view

 

Dufourea fimbriata genitalia, ventral view

Distribution:

In Canada, this species is known from very few specimens; Alberta (Edmonton), northern Ontario and Northwest Territories (Yellowknife) (see Map).