Railroad worm

Not to be confused with Apple maggot.

Railroad worm
Railroad worm with lights both on and off
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Family: Phengodidae
Genus: Phrixothrix
E.Olivier, 1909
Species

(several)

A railroad worm is a larva or larviform female adult of a beetle of the genus Phrixothrix in the family Phengodidae, characterized by the possession of two different colors of bioluminescence.[1] It has the appearance of a caterpillar. The eleven pairs of luminescent organs on their second thoracic segment through their ninth abdominal segment can glow yellowish-green, while the pair on their head can glow red;[1] this is due to different luciferases in their bodies, as the reaction substrate, called luciferin, is the same.[2]

The "railroad worm" name arises because these glowing spots along the body resemble the windows of train cars internally illuminated in the night.[1] The light emissions are believed to be a warning signal to nocturnal predators of their unpalatability or a defense function as they can suddenly be turned on, spooking predators with a sudden flash. When handled, the larva may eject a possibly distasteful and corrosive reddish liquid.[1]

The term "railroad worm" is also sometimes applied to the apple maggot.[3]

  1. ^ a b c d Branham, Marc (February 2005). "EENY332/IN609: Glow-Worms, Railroad-Worms (Insecta: Coleoptera: Phengodidae)". edis.ifas.ufl.edu. University of Florida, Institute of Food and Agricultural Sciences. Retrieved 2016-10-11.
  2. ^ Bevilaqua, V. R.; Matsuhashi, T.; Oliveira, G.; Oliveira, P. S. L.; Hirano, T.; Viviani, V. R. (2019). "Phrixotrix luciferase and 6′-aminoluciferins reveal a larger luciferin phenolate binding site and provide novel far-red combinations for bioimaging purposes". Scientific Reports. 9 (1): 8998. doi:10.1038/s41598-019-44534-3. ISSN 2045-2322. PMC 6588592. PMID 31227722.
  3. ^ "apple maggot - Rhagoletis pomonella (Walsh)". entomology.ifas.ufl.edu. University of Florida, Institute of Food and Agricultural Sciences. March 2015. Retrieved 2016-10-11.