Article · Wikipedia archive · Last revised Jun 25, 2026

Atractelmis

Atractelmis is a genus of riffle beetles in the family Elmidae. The genus is monotypic, the sole species being Atractelmis wawona, also known as the Wawona riffle beetle. It is endemic to the Western United States between California, Oregon, and Idaho. The specific name wawona refers to its type locality, Wawona in the Yosemite National Park.

Last revised
Jun 25, 2026
Read time
≈ 1 min
Length
326 w
Citations
15
Source
Atractelmis
Atractelmis on image N.O 58 and N.0 59
Vulnerable
Vulnerable (NatureServe)1
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Arthropoda
Clade: Pancrustacea
Class: Insecta
Order: Coleoptera
Suborder: Polyphaga
Infraorder: Elateriformia
Family: Elmidae
Genus: Atractelmis
Chandler, 19542
Species:
A. wawona
Binomial name
Atractelmis wawona
Chandler, 19542

Atractelmis is a genus of riffle beetles in the family Elmidae. The genus is monotypic, the sole species being Atractelmis wawona,34 also known as the Wawona riffle beetle.15 It is endemic to the Western United States between California, Oregon, and Idaho.15 The specific name wawona refers to its type locality, Wawona in the Yosemite National Park.2

Habitat

Atractelmis wawona occur in riffles of rapid clear mountain streams at 600–1,500 m (2,000–5,000 ft) above sea level.1 Adults and larvae occur in the same microhabitats and are typically found in aquatic mosses, particularly Platyhypnidium riparioides.6 These beetles are easily overlooked but can be locally numerous.1

Description

Adults measure about 2 mm (0.079 in) in length and 0.9 mm (0.035 in) in width. They are shiny black above with four red spots on the elytra.2 The larvae can grow to 4.8–5 mm (0.19–0.20 in) in length.6

References

References

  1. "Atractelmis wawona Wawona Riffle Beetle". NatureServe. 10 October 2025. Retrieved 20 October 2025.
  2. Chandler, H. P. (1954). "New genera and species of Elmidae (Coleoptera) from California". Pan-Pacific Entomologist. 30 (2): 125–131. ISSN 0031-0603.
  3. "Atractelmis Chandler, 1954". Integrated Taxonomic Information System. Retrieved 20 October 2025.
  4. "Atractelmis Chandler, 1954". Global Biodiversity Information Facility. Retrieved 20 October 2025.
  5. Shepard, W. D.; Barr, Cheryl B. (1991). "Description of the larva of Atractelmis (Coleoptera: Elmidae) and new information on the morphology, distribution, and habitat of Atractelmis wawona Chandler". Pan-Pacific Entomologist. 67 (3): 195––199.
Further reading

Further reading