The nematode Caenorhabditis elegans and the terrestrial isopod Porcellio scaber likely interact opportunistically

PLoS One. 2020 Jun 26;15(6):e0235000. doi: 10.1371/journal.pone.0235000. eCollection 2020.


Phoresy is a behavior in which an organism, the phoront, travels from one location to another by 'hitching a ride' on the body of a host as it disperses. Some phoronts are generalists, taking advantage of any available host. Others are specialists and travel only when specific hosts are located using chemical cues to identify and move (chemotax) toward the preferred host. Free-living nematodes, like Caenorhabditis elegans, are often found in natural environments that contain terrestrial isopods and other invertebrates. Additionally, the C. elegans wild strain PB306 was isolated associated with the isopod Porcellio scaber. However, it is currently unclear if C. elegans is a phoront of terrestrial isopods, and if so, whether it is a specialist, generalist, or developmental stage-specific combination of both strategies. Because the relevant chemical stimuli might be secreted compounds or volatile odorants, we used different types of chemotaxis assays across diverse extractions of compounds or odorants to test whether C. elegans is attracted to P. scaber. We show that two different strains-the wild isolate PB306 and the laboratory-adapted strain N2 -are not attracted to P. scaber during either the dauer or adult life stages. Our results indicate that C. elegans was not attracted to chemical compounds or volatile odorants from P. scaber, providing valuable empirical evidence to suggest that any associations between these two species are likely opportunistic rather than specific phoresy.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Caenorhabditis elegans / isolation & purification
  • Caenorhabditis elegans / physiology*
  • Chemotaxis / physiology
  • Host-Parasite Interactions / physiology*
  • Isopoda / parasitology*
  • Isopoda / physiology
  • Life Cycle Stages
  • Odorants

Grant support

This work was funded by an NSF CAREER Award (1751035) to E.C.A. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.