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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
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)
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)
our spp., 2-5 mm; worldwide, 1-17 mm(5)
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.
throughout the world and much of the US
under leaf litter, rocks, bark
Life Cycle
Some species form swarms in sunny patches in woodland, resembling the behavior of midges(1)
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