| Home | Table of contents | Keys | Species list | Glossary | Image data | PDF | Cite this article | Feedback | Updates |

Identification Atlas of the Vespidae (Hymenoptera, Aculeata) of the northeastern Nearctic region
CJAI 05, February 19, 2008
doi: 10.3752/cjai.2008.05

Matthias Buck, Stephen A. Marshall, and David K.B. Cheung

Department of Environmental Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1

 

Next species | Previous species | Key

66. Symmorphus cristatus (de Saussure, 1855)
Figs B8.5, 7, 9; C66.1–5.

Symmorphus cristatus Symmorphus cristatus Symmorphus cristatus
Symmorphus cristatus Symmorphus cristatus Symmorphus cristatus Symmorphus cristatus

Species recognition. In many ways this species is morphologically intermediate between S. albomarginatus and S. canadensis. Differences are listed in the key and discussed under the other two species. Male flagellomere XI is shorter than in other species (length 0.55–0.71x width; 0.75–0.94x in S. canadensis, 1.00–1.20 in S. albomarginatus; Cumming 1989).

Variation. Fore wing length 5.0–7.0 mm (♂♂), 5.5–9.0 mm (♀♀). Body with pale markings usually ivory or pale yellow, bright yellow only in specimens from Carolinian Life Zone and further south. Female clypeus with pale basal spot usually small, often absent; male clypeus rarely with a narrow preapical black band. Interantennal spot rarely absent in male. Female with anteroventral surface of scape black (exceptionally so in male), rarely with small pale basal mark. Pronotum with a pair of pale spots of variable size, very small to absent in some males. Male sometimes without pair of pale spots on scutellum. Tegula black to amber. Apical fasciae typically developed on terga 1, 2 and 4, in male sometimes also on 3 and 5. Sternum 2 with posterolateral pale spots or an interrupted fascia; occasionally sternum 4 and more rarely 3 with posterolateral spots, in male sometimes also 5 and 6.

Distribution. Transcontinental in Canada and northern U.S., south to NC, NE, NM and CA (Cumming 1989).

Biology. Nests in borings in wood and sumac stems, and provisions with free-living Chrysomelinae larvae (Krombein 1967, 1979).

 

Next species | Previous species | Key

 

| Home | Table of contents | Keys | Species list | Glossary | Image data | PDF | Cite this article | Feedback | Updates |