Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes



Genus Macrosiagon

Unknown Beetle - Macrosiagon pectinata - female Wedge-shaped beetle - Macrosiagon cruenta - female unknown - Macrosiagon sayi - female Macrosiagon - Macrosiagon pectinata - female Macrosiagon pectinatum? - Macrosiagon octomaculata - female Female Macrosiagon 1 - Macrosiagon flavipennis - female Beetle - Macrosiagon Is this Macrosiagon flavipennis? - Macrosiagon
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga
No Taxon (Series Cucujiformia)
Superfamily Tenebrionoidea
Family Ripiphoridae (Wedge-shaped Beetles)
Subfamily Ripiphorinae
Genus Macrosiagon
Explanation of Names
Macrosiagon Hentz 1830
Greek 'large jaw' --refers to the enlarged mouthparts:

The grammatical gender is feminine, thus the -a endings of the specific epithets. (Zack Falin, pers. comm. to =v=, 21.xii.2009)
the largest genus in the family, with 11 spp. in our area and ~160 worldwide(1); 7 spp. in NC & SC(2)(3), 8 in FL(4), 2 reach Canada(5)
not yet in guide: M. bifoveata (Horn) - IL, TX; M. fernalda Rivnay - CA
4-12 mm
Elytra cover most of abdomen. Thorax has projection covering scutellum. Usually colored black and orange. In females, abdomen blunt, antennae mostly serrate; in males, abdomen more pointed, antennae pectinate. Color varies greatly within species.
keys and descriptions in(6)(7)(8)
Worldwide; in NA, much of the US + ON & SK(1)(5)
adults usually on flowers, esp. Asteraceae(1)
Larvae are parasitoids of wasps and bees (Vespidae, Sphecidae, Crabronidae, Pompilidae, Apidae, etc.) +Host associations: M. cruenta, twig-nesting Eumeninae; M. flavipennis, Bembix; Scoliidae, Tiphiidae(9); hosts in Cuba, Indonesia
Life Cycle
eggs laid on flowers and hatch into an active larva (triungulin) that attaches itself to visiting wasp/bee and is carried to the nest where it burrows into a host larva
our only representative of the tribe Macrosiagonini Heyden 1908(1)
Works Cited
1.American Beetles, Volume II: Polyphaga: Scarabaeoidea through Curculionoidea
Arnett, R.H., Jr., M. C. Thomas, P. E. Skelley and J. H. Frank. (eds.). 2002. CRC Press LLC, Boca Raton, FL.
2.Insects of North Carolina
C.S. Brimley. 1938. North Carolina Department of Agriculture.
3.Tenebrionoidea of South Carolina
Janet C. Ciegler. 2014. Clemson University.
4.A Distributional Checklist of the Beetles (Coleoptera) of Florida
5.Checklist of beetles (Coleoptera) of Canada and Alaska. Second edition
Bousquet Y., Bouchard P., Davies A.E., Sikes D.S. 2013. ZooKeys 360: 1–402.
6.Revision of the Rhipiphoridae of North and Central America
Ezekiel Rivnay. 1929. American Entomological Society.
7.A review of the genus Macrosiagon in Mexico, with notes on Rhipiphorus (Coleoptera, Rhipiphoridae)
Patricia Vaurie. 1955. American Museum of Natural History.
8.The Rhipiphoridae of California (Coleptera)
Linsley E.G., MacSwain J.W. 1951. Bull. Calif. Insect Surv. 1: 79-88.
9.The Wasps
Howard Ensign Evans, Mary Jane West Eberhard. 1970. University of Michigan Press.