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

Calendar
Upcoming Events

Photos of insects and people from the 2022 BugGuide gathering in New Mexico, July 20-24

National Moth Week was July 23-31, 2022! See moth submissions.

Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

Photos of insects and people from the 2019 gathering in Louisiana, July 25-27

Photos of insects and people from the 2018 gathering in Virginia, July 27-29

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12


Previous events


TaxonomyBrowse
Info
ImagesLinksBooksData

Family Enicocephalidae - Gnat Bugs

Unique-headed Bug - Systelloderes biceps Systelloderes sp. - Systelloderes Unique-headed Bug Enicocephalidae - Systelloderes Gnat bug from north central Texas Systelloderes - male bug - Systelloderes Systelloderes sp. - Systelloderes Enicocephalid
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hemiptera (True Bugs, Cicadas, Hoppers, Aphids and Allies)
Suborder Heteroptera (True Bugs)
Infraorder Enicocephalomorpha (Unique-headed Bugs)
Family Enicocephalidae (Gnat Bugs)
Other Common Names
Unique-headed Bugs(1)(2)
Numbers
poorly understood group(3) with ~10 spp. in 2 genera in our area and >400 spp. in 55 genera worldwide(4)
in our area: Boreostolus (2 spp., nw. US & ne. Asia): B. americanus Wygodzinsky & Stys 1970 (nw. US); Systelloderes (genus needs revision)
Size
our spp., 2-5 mm; worldwide, 1-17 mm(5)
Identification
slender body with unusual elongated head constricted behind eyes and at base; ocelli present; antennae and beak 4-segmented; forewings entirely membranous; front femora and tarsi thickened; middle and hind tarsi 2-segmented.
Range
throughout the world and much of the US
Habitat
under leaf litter, rocks, bark
Food
Predacious(2)
Life Cycle
Some species form swarms in sunny patches in woodland, resembling the behavior of midges(1)
Remarks
may form aggregations of many thousands of individuals(4), but tend to be scarce in collections
Works Cited
1.How to Know the True Bugs
Slater, James A., and Baranowski, Richard M. 1978. Wm. C. Brown Company.
2.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.
3.Revision of the New World Enicocephalomorpha (Heteroptera)
Wygodzinsky, P.W. and K. Schmidt. 1991. Bulletin of the American Museum of Natural History ; no. 200.
4.Biodiversity of the Heteroptera
Henry T.J. 2009. In: Foottit R.G., Adler P.H., eds. Insect biodiversity: Science and society. Oxford: Wiley-Blackwell: 223-263.
5.Australian Faunal Directory