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

Upcoming Events

National Moth Week photos of insects and people. Here's how to add your images.

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

Discussion, 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

Photos of insects and people from the 2014 gathering in Virginia, June 4-7.

Photos of insects and people from the 2013 gathering in Arizona, July 25-28

Photos of insects and people from the 2012 gathering in Alabama

Photos of insects and people from the 2011 gathering in Iowa


Species Heterelmis comalensis - Comal Springs Riffle Beetle

Comal Springs Riffle Beetle - Heterelmis comalensis Comal Springs Riffle Beetle - Heterelmis comalensis Comal Springs Riffle Beetle - Heterelmis comalensis Heterelmis comalensis
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga (Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles)
No Taxon (Series Elateriformia)
Superfamily Byrrhoidea (Pill, Water and Toe-winged Beetles)
Family Elmidae (Riffle Beetles)
Subfamily Elminae
Tribe Elmini
Genus Heterelmis
Species comalensis (Comal Springs Riffle Beetle)
Explanation of Names
Heterelmis comalensis Bosse, Tuff, and Brown, 1988
5 spp. n. of Mex (1)
Male-Length 1.7 to 2.1 mm;
Female averaging slightly larger. (Bosse et al., 1988).
H. comalensis is the smallest of the Heterelmis species (n = 5) in the US, is the only species of Heterelmis with vestigial hind wings, and is flightless (Bosse et al., 1988).
endemic to two spring complexes in the Texas Hill Country, Comal Springs [Comal Co.] and San Marcos Springs [Hays Co.] (Gonzales 2008)
Usual water depth in occupied habitat is 2 to 10 centimeters (cm)(1 to 4 in) although the beetle may also occur in slightly deeper areas within the spring runs. (Gonzales 2008)
Type Locality: Texas, Comal County, Comal River, Landa Park Springs, 9 April 1976, L. S. Bosse, collector.
Texas Parks & Wildlife considers this to be a "Species of Greatest Conservation Need" (SGCN) (2)
Print References
Bosse, L.S., D.W. Tuff, and H.P. Brown. 1988. A new species of Heterelmis from Texas (Coleoptera: Elmidae). Southwestern Naturalist 33: 199-203. Full Text
Bowles, D.E., Barr, C.B., and Stanford, R. 2003. Habitat and phenology of the endangered riffle beetle Heterelmis comalensis and a coexisting species, Microcylloepus pusillus, (Coleoptera: Elmidae) at Comal Springs, Texas, USA. Arch. Hydrobiol. 156(3): 361-383. Abstract
Fries, J.N. 2004. Possible reproduction of the Comal Springs riffle beetle, Heterelmis comalensis (Coleoptera: Elmidae), in captivity. Entomological News 114(1): 7-9. Abstract
Gibson, J.R., S.J. Harden, and J.N. Fries. 2008. Survey and distribution of invertebrates from selected springs of the Edwards Aquifer in Comal and Hays Counties, Texas. Southwestern Naturalist 53: 74-84. Abstract
Gonzales, T.K. 2008. Conservation Genetics of the Comal Springs Riffle Beetle (Heterelmis comalensis) Populations in Central Texas, with Examination of Molecular and Morphological Variation in Heterelmis Sp. Throughout Texas. Texas State University-San Marcos, Theses and Dissertations-Biology. 67 pp. Full PDF, Abstract
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.Texas "Species of Greatest Conservation Need" (SGCN) - TPWD