Stephan's Riffle Beetle

Heterelmis is a genus of beetles in the riffle beetle family Elmidae and contains 22 extant species and 1 species that is presumed to be extinct.
Species include:

Heterelmis apicata (Grouvelle, 1896)
Heterelmis cervina (Grouvelle, 1896)
Heterelmis comalensis Bosse, Tuff, and Brown, 1988
Heterelmis convexicollis Delève, 1968
Heterelmis debilis Polizei 2018
Heterelmis dubia Grouvelle, 1889
Heterelmis gibbosa (Grouvelle, 1889)
Heterelmis glabra (Horn, 1870)
Heterelmis impressicollis Delève, 1968
Heterelmis limnoides Hinton, 1936
Heterelmis longior (Grouvelle, 1896)
Heterelmis longula Sharp, 1887
Heterelmis lucida Delève, 1968
Heterelmis neglecta Grouvelle, 1896
Heterelmis obesa Hinton, 1936
Heterelmis obscura Sharp, 1882
Heterelmis pusilla Delève, 1968
Heterelmis simplex Sharp 1882
†Heterelmis stephani Brown, 1972
Heterelmis tarsalis (Germain, 1892)
Heterelmis trivialis (Germain, 1892)
Heterelmis vilcanota Spangler, 1980
Heterelmis vulnerata (LeConte, 1874)