Dufourea, Lepeletier

Gibbs, Jason, Dumesh, Sheila & Griswold, Terry L., 2014, Bees of the genera Dufourea and Dieunomia of Michigan (Hymenoptera: Apoidea: Halictidae), with a key to the Dufourea of eastern North America, Journal of Melittology 2014 (29), pp. 1-15 : 9-10

Key to species of Dufourea in eastern North America

[All species except D. marginata have been recorded from Michigan.]

1. Both sexes: Pubescence of body very dark ( Fig. 2 ); compound eyes diverging below ( Fig. 1 ). Male: Metasomal sternum six with strong ventrally-directed keel ( Fig. 2 ) (specialist on Campanula ; alpine/boreal distribution) ............. D. maura (Cresson)

—. Both sexes: Pubescence of body light in part ( Fig. 3 ); compound eyes parallel or converging below. Male: Metasomal sternum six with apically-directed keel ( Fig. 3 ) ........................................................................................................................... 2

2(1). Both sexes: Head longer than wide ( Fig. 4 ) ............................................................. 3

—. Both sexes: Head wider than long ( Fig. 5 ) ............................................................... 4

3(2). Female: Mouthparts (stipes, first labial palpomere) with abundant setae ( Fig. 6 ); mesobasitarsus bowed posteriorly, width at midpoint distinctly greater than apex ( Fig. 7 ). Male: Posterior margin of propodeal dorsum rugulose ( Fig. 10 ); metatrochanter with ventral angle acute ( Fig. 11 ); metasomal sternum six with oblique submedial swellings carinate ( Fig. 12 ) (specialist on Pontederia ) .............. .......................................................................................... D. novaeangliae (Robertson)

—. Female: Mouthparts bare ( Fig. 8 ); mesobasitarsus parallel-sided, width at midpoint subqual to apex ( Fig. 9 ). Male: Posterior margin of propodeal dorsum imbricate ( Fig. 13 ); metatrochanter with ventral angle obtuse ( Fig. 14 ); metasomal sternum six with oblique submedial swellings acarinate ( Fig. 15 ) (specialist on Monarda ) ................................................................................... D. monardae (Viereck)

4(2). Both sexes: Mesoscutum shiny, sparsely punctate across disc. Female: Clypeus with coarse punctures evenly distributed across surface ( Fig. 16 ); mesotibial spur long, more than half as long as mesobasitarsus ( Fig. 17 ). Male: Posterior margin of metasomal sternum five concave ( Fig. 18 ); sternum six with low submedial ridge on each side of medial carina (specialist on Potentilla ) ...................... .................................................................................................... D. harveyi (Cockerell)

—. Both sexes: Mesoscutum dull, contiguously punctate across disc. Female: Clypeus with fine punctures concentrated basally, clypeus impunctate apicomedially ( Fig. 19 ); mesotibial spur short, less than half as long as mesobasitarsus ( Fig. 20 ). Male: Posterior margin of metasomal sternum five straight ( Fig. 21 ); sternum six without submedial ridge on each side of medial carina (specialist on Helianthus ) ......................................................................... D. marginata (Cresson)

Figures

Figure 1. Face of female Dufourea maura (Cresson). Modified from Dumesh & Sheffield (2012). Scale bar = 1 mm.

Figures 2–3. Lateral habitus of male Dufourea Lepeletier de Saint Fargeau. 2. Dufourea maura (Cresson). 3. D. harveyi (Cockerell). Modified from Dumesh & Sheffield (2012).

Figures 4–5. Faces of female Dufourea Lepeletier de Saint Fargeau. 4. Dufourea novaeangliae (Robertson). 5. D. harveyi (Cockerell). Modified from Dumesh & Sheffield (2012).

Figures 6–9. Females of Dufourea novaeangliae (Robertson) (6, 7) and D. monardae (Viereck) (8, 9). 6, 8. Head and mouthparts in lateral view. 7, 9. Mesobasitarsi. Modified from Dumesh & Sheffield (2012).

Figures 10–15. Males of Dufourea novaeangliae (Robertson) (10–12) and D. monardae (Viereck) (13–15). 10, 13. Propodea. 11, 14. Metatrochanters. 12, 15. Metasomal sterna six. Modified from Dumesh & Sheffield (2012).

Figures 16–21. Male Dufourea harveyi (Cockerell) (16–18) and D. marginata (Cresson) (19–21). 16, 19. Clypea. 17, 20. Inner metatibial spurs. 21, 22. Metasomal sterna five and six. Modified from Dumesh & Sheffield (2012).