Texas Beetle Information

Return to Texas Entomology - Compiled by Mike Quinn

Glowworm Beetle

Phengodes sp.

Family Phengodidae, Subfamily Phengodinae

Soft-bodied beetles with bioluminescent larviform females and larvae

(male Phengodes sp. have plumose antennae & short, pointed elytra)

Austin, Travis Co., TX
June 14, 2006 (Joe Lapp)


(Adult female Phengodes sp. are larviform)

Val Verde County, Texas
June 2007


Females emit light as a defensive mechanism; adult females appear to be larviform
Males have prominent branched antennae to detect the female's pheromones; reduced elytra (forewings), and large bulging eyes.


Males are attracted to females at a distance by pheromones, and at close range by the female's bioluminescent organs.

Similar Species

Over 250 species of Phengodidae occur in the Western Hemisphere, of which 23 species occur in the U.S. (Arnett, 2002).
Of the 10 species of Phengodes (s. str.), 7 occur in the southwestern (Arizona), central, and eastern United States, and 3 others occur in Mexico.

Texas Taxa:

Phengodes frontalis LeConte 
Phengodes fusciceps LeConte


Glow-worms, Railroad-worms - Featured Creatures - University of Florida

Phengodidae (Glowworm Beetles) - BugGuide


Phengodidae (Glowworm Beetles) - BugGuide


Glowing Photos:

female Phengodes sp.1 glowing - University of Florida

female Phengodes sp. 2 glowing - University of Florida


Pheng, -o (G). Light

-od (NL). Form


Arnett, R.H., Jr., M.C. Thomas, P.E. Skelley & J.H. Frank. (editors). 2002. American Beetles, Volume II: Polyphaga: Scarabaeoidea through Curculionoidea. CRC Press LLC, Boca Raton, FL. xiv + 861 pp.

Borror, D.J. 1960. Dictionary of Word Roots and Combining Forms. National Press Books, Palo Alto. 134 pp.

Lawrence J.F., Hastings A.M., Dallwitz M.J., Paine T.A., Zurcher E.J. 1999. Beetles of the World: A Key and Identification System for Families and Subfamilies. (CD-ROM Version 1.0 for Windows). CSIRO Publishing, Melbourne.

Lloyd, J.E. 1971. Bioluminescent Communication in Insects. Annual Review of Entomology, 16: 97-122.

Lloyd, J. E. 1979. Sexual selection in luminescent beetles. Pp. 293-342 in: M.S. and N.A. Blum (editors), Sexual selection and reproductive competition in insects. Academic Press, NY. 463 pp.

Lloyd, J. E. 1983. Bioluminescence and Communication in Insects. Annual Review of Entomology, 28: 131-160.

Taber, S.W. & S.B. Fleenor. 2003. Insects of the Texas Lost Pines. Texas A&M University, College Station. 283 pp.

Tiemann D. 1967. Observation on the natural history of the western banded glow-worm Zarhipis integripennis. Proceedings of the California Academy of Sciences 35: 235-264.

Wittmer W. 1975. The genus Phengodes in the United States (Coleoptera: Phengodidae). Coleopterists Bulletin 29:231-250.

03 Oct 2009   Mike Quinn / entomike@gmail.com / Texas Entomology / Texas Beetle Information